NICK BOSTROM

Are You Living In a Computer Simulation?

Nick Bostrom (born Niklas Boström in 1973) is a Swedish philosopher at the University of Oxford known for his work on existential risk and the Anthropic principle. He holds a PhD from the London School of Economics (2000). He is currently the director of The Future of Humanity Institute at Oxford University.

In addition to his writing for academic and popular press, Bostrom makes frequent media appearances in which he talks about transhumanism-related topics such as cloning, artificial intelligence, superintelligence, mind uploading, cryonics, nanotechnology, and the simulation argument.

In 1998, Bostrom co-founded (with David Pearce) the World Transhumanist Association (which has since changed its name to Humanity+). In 2004, he co-founded (with James Hughes) the Institute for Ethics and Emerging Technologies. Bostrom currently serves as the Chair of both organizations. In 2005 he was appointed Director of the newly created Oxford Future of Humanity Institute. Bostrom is the 2009 finalist in philosophy for and potential first ever recipient of the Eugene R. Gannon Award for the Continued Pursuit of Human Advancement.

Are You Living In a Computer Simulation?

BY NICK BOSTROM
Department of Philosophy, Oxford University

I. INTRODUCTION

Many works of science fiction as well as some forecasts by serious technologists and futurologists predict that enormous amounts of computing power will be available in the future. Let us suppose for a moment that these predictions are correct. One thing that later generations might do with their super-powerful computers is run detailed simulations of their forebears or of people like their forebears. Because their computers would be so powerful, they could run a great many such simulations. Suppose that these simulated people are conscious (as they would be if the simulations were sufficiently fine-grained and if a certain quite widely accepted position in the philosophy of mind is correct). Then it could be the case that the vast majority of minds like ours do not belong to the original race but rather to people simulated by the advanced descendants of an original race. It is then possible to argue that, if this were the case, we would be rational to think that we are likely among the simulated minds rather than among the original biological ones. Therefore, if we don’t think that we are currently living in a computer simulation, we are not entitled to believe that we will have descendants who will run lots of such simulations of their forebears. That is the basic idea. The rest of this paper will spell it out more carefully.

Apart from the interest this thesis may hold for those who are engaged in futuristic speculation, there are also more purely theoretical rewards. The argument provides a stimulus for formulating some methodological and metaphysical questions, and it suggests naturalistic analogies to certain traditional religious conceptions, which some may find amusing or thought-provoking.

The structure of the paper is as follows. First, we formulate an assumption that we need to import from the philosophy of mind in order to get the argument started. Second, we consider some empirical reasons for thinking that running vastly many simulations of human minds would be within the capability of a future civilization that has developed many of those technologies that can already be shown to be compatible with known physical laws and engineering constraints. This part is not philosophically necessary but it provides an incentive for paying attention to the rest. Then follows the core of the argument, which makes use of some simple probability theory, and a section providing support for a weak indifference principle that the argument employs. Lastly, we discuss some interpretations of the disjunction, mentioned in the abstract, that forms the conclusion of the simulation argument.

II. THE ASSUMPTION OF SUBSTRATE-INDEPENDENCE

A common assumption in the philosophy of mind is that of substrate-independence. The idea is that mental states can supervene on any of a broad class of physical substrates. Provided a system implements the right sort of computational structures and processes, it can be associated with conscious experiences. It is nor an essential property of consciousness that it is implemented on carbon-based biological neural networks inside a cranium: silicon-based processors inside a computer could in principle do the trick as well.

Arguments for this thesis have been given in the literature, and although it is not entirely uncontroversial, we shall here take it as a given.

The argument we shall present does not, however, depend on any very strong version of functionalism or computationalism. For example, we need not assume that the thesis of substrate-independence is necessarily true (either analytically or metaphysically) – just that, in fact, a computer running a suitable program would be conscious. Moreover, we need not assume that in order to create a mind on a computer it would be sufficient to program it in such a way that it behaves like a human in all situations, including passing the Turing test etc. We need only the weaker assumption that it would suffice for the generation of subjective experiences that the computational processes of a human brain are structurally replicated in suitably fine-grained detail, such as on the level of individual synapses. This attenuated version of substrate-independence is quite widely accepted.

Neurotransmitters, nerve growth factors, and other chemicals that are smaller than a synapse clearly play a role in human cognition and learning. The substrate-independence thesis is not that the effects of these chemicals are small or irrelevant, but rather that they affect subjective experience only via their direct or indirect influence on computational activities. For example, if there can be no difference in subjective experience without there also being a difference in synaptic discharges, then the requisite detail of simulation is at the synaptic level (or higher).


III. THE TECHNOLOGICAL LIMITS OF COMPUTATION

At our current stage of technological development, we have neither sufficiently powerful hardware nor the requisite software to create conscious minds in computers. But persuasive arguments have been given to the effect that if technological progress continues unabated then these shortcomings will eventually be overcome. Some authors argue that this stage may be only a few decades away. Yet present purposes require no assumptions about the time-scale. The simulation argument works equally well for those who think that it will take hundreds of thousands of years to reach a “posthuman” stage of civilization, where humankind has acquired most of the technological capabilities that one can currently show to be consistent with physical laws and with material and energy constraints.

Such a mature stage of technological development will make it possible to convert planets and other astronomical resources into enormously powerful computers. It is currently hard to be confident in any upper bound on the computing power that may be available to posthuman civilizations. As we are still lacking a “theory of everything”, we cannot rule out the possibility that novel physical phenomena, not allowed for in current physical theories, may be utilized to transcend those constraints that in our current understanding impose theoretical limits on the information processing attainable in a given lump of matter. We can with much greater confidence establish lower bounds on posthuman computation, by assuming only mechanisms that are already understood. For example, Eric Drexler has outlined a design for a system the size of a sugar cube (excluding cooling and power supply) that would perform 10^21 instructions per second. Another author gives a rough estimate of 10^42 operations per second for a computer with a mass on order of a large planet. (If we could create quantum computers, or learn to build computers out of nuclear matter or plasma, we could push closer to the theoretical limits. Seth Lloyd calculates an upper bound for a 1 kg computer of 5*10^50 logical operations per second carried out on ~10^31 bits. However, it suffices for our purposes to use the more conservative estimate that presupposes only currently known design-principles.)The amount of computing power needed to emulate a human mind can likewise be roughly estimated. One estimate, based on how computationally expensive it is to replicate the functionality of a piece of nervous tissue that we have already understood and whose functionality has been replicated in silico, contrast enhancement in the retina, yields a figure of ~10^14 operations per second for the entire human brain. An alternative estimate, based the number of synapses in the brain and their firing frequency, gives a figure of ~10^16-10^17 operations per second. Conceivably, even more could be required if we want to simulate in detail the internal workings of synapses and dendritic trees. However, it is likely that the human central nervous system has a high degree of redundancy on the mircoscale to compensate for the unreliability and noisiness of its neuronal components. One would therefore expect a substantial efficiency gain when using more reliable and versatile non-biological processors.

Memory seems to be a no more stringent constraint than processing power. Moreover, since the maximum human sensory bandwidth is ~10^8 bits per second, simulating all sensory events incurs a negligible cost compared to simulating the cortical activity. We can therefore use the processing power required to simulate the central nervous system as an estimate of the total computational cost of simulating a human mind.

If the environment is included in the simulation, this will require additional computing power – how much depends on the scope and granularity of the simulation. Simulating the entire universe down to the quantum level is obviously infeasible, unless radically new physics is discovered. But in order to get a realistic simulation of human experience, much less is needed – only whatever is required to ensure that the simulated humans, interacting in normal human ways with their simulated environment, don’t notice any irregularities. The microscopic structure of the inside of the Earth can be safely omitted. Distant astronomical objects can have highly compressed representations: verisimilitude need extend to the narrow band of properties that we can observe from our planet or solar system spacecraft. On the surface of Earth, macroscopic objects in inhabited areas may need to be continuously simulated, but microscopic phenomena could likely be filled in ad hoc. What you see through an electron microscope needs to look unsuspicious, but you usually have no way of confirming its coherence with unobserved parts of the microscopic world. Exceptions arise when we deliberately design systems to harness unobserved microscopic phenomena that operate in accordance with known principles to get results that we are able to independently verify. The paradigmatic case of this is a computer. The simulation may therefore need to include a continuous representation of computers down to the level of individual logic elements. This presents no problem, since our current computing power is negligible by posthuman standards.

Moreover, a posthuman simulator would have enough computing power to keep track of the detailed belief-states in all human brains at all times. Therefore, when it saw that a human was about to make an observation of the microscopic world, it could fill in sufficient detail in the simulation in the appropriate domain on an as-needed basis. Should any error occur, the director could easily edit the states of any brains that have become aware of an anomaly before it spoils the simulation. Alternatively, the director could skip back a few seconds and rerun the simulation in a way that avoids the problem.

It thus seems plausible that the main computational cost in creating simulations that are indistinguishable from physical reality for human minds in the simulation resides in simulating organic brains down to the neuronal or sub-neuronal level. While it is not possible to get a very exact estimate of the cost of a realistic simulation of human history, we can use ~10^33 - 10^36 operations as a rough estimate. As we gain more experience with virtual reality, we will get a better grasp of the computational requirements for making such worlds appear realistic to their visitors. But in any case, even if our estimate is off by several orders of magnitude, this does not matter much for our argument. We noted that a rough approximation of the computational power of a planetary-mass computer is 10^42 operations per second, and that assumes only already known nanotechnological designs, which are probably far from optimal. A single such a computer could simulate the entire mental history of humankind (call this an ancestor-simulation) by using less than one millionth of its processing power for one second. A posthuman civilization may eventually build an astronomical number of such computers. We can conclude that the computing power available to a posthuman civilization is sufficient to run a huge number of ancestor-simulations even it allocates only a minute fraction of its resources to that purpose. We can draw this conclusion even while leaving a substantial margin of error in all our estimates.
· Posthuman civilizations would have enough computing power to run hugely many ancestor-simulations even while using only a tiny fraction of their resources for that purpose.

IV. THE CORE OF THE SIMULATION ARGUMENT

The basic idea of this paper can be expressed roughly as follows: If there were a substantial chance that our civilization will ever get to the posthuman stage and run many ancestor-simulations, then how come you are not living in such a simulation?

We shall develop this idea into a rigorous argument. Let us introduce the following notation:

The actual fraction of all observers with human-type experiences that live in simulations is then

Writing f1 for the fraction of posthuman civilizations that are interested in running ancestor-simulations (or that contain at least some individuals who are interested in that and have sufficient resources to run a significant number of such simulations), and N1 for the average number of ancestor-simulations run by such interested civilizations, we have
and thus:
Because of the immense computing power of posthuman civilizations, N1 is extremely large, as we saw in the previous section. By inspecting (*) we can then see that at least one of the following three propositions must be true:

V. A BLAND INDIFFERENCE PRINCIPLE

We can take a further step and conclude that conditional on the truth of (3), one’s credence in the hypothesis that one is in a simulation should be close to unity. More generally, if we knew that a fraction x of all observers with human-type experiences live in simulations, and we don’t have any information that indicate that our own particular experiences are any more or less likely than other human-type experiences to have been implemented in vivo rather than in machina, then our credence that we are in a simulation should equal x:

This step is sanctioned by a very weak indifference principle. Let us distinguish two cases. The first case, which is the easiest, is where all the minds in question are like your own in the sense that they are exactly qualitatively identical to yours: they have exactly the same information and the same experiences that you have. The second case is where the minds are “like” each other only in the loose sense of being the sort of minds that are typical of human creatures, but they are qualitatively distinct from one another and each has a distinct set of experiences. I maintain that even in the latter case, where the minds are qualitatively different, the simulation argument still works, provided that you have no information that bears on the question of which of the various minds are simulated and which are implemented biologically.

A detailed defense of a stronger principle, which implies the above stance for both cases as trivial special instances, has been given in the literature. Space does not permit a recapitulation of that defense here, but we can bring out one of the underlying intuitions by bringing to our attention to an analogous situation of a more familiar kind. Suppose that x% of the population has a certain genetic sequence S within the part of their DNA commonly designated as “junk DNA”. Suppose, further, that there are no manifestations of S (short of what would turn up in a gene assay) and that there are no known correlations between having S and any observable characteristic. Then, quite clearly, unless you have had your DNA sequenced, it is rational to assign a credence of x% to the hypothesis that you have S. And this is so quite irrespective of the fact that the people who have S have qualitatively different minds and experiences from the people who don’t have S. (They are different simply because all humans have different experiences from one another, not because of any known link between S and what kind of experiences one has.)

The same reasoning holds if S is not the property of having a certain genetic sequence but instead the property of being in a simulation, assuming only that we have no information that enables us to predict any differences between the experiences of simulated minds and those of the original biological minds.

It should be stressed that the bland indifference principle expressed by (#) prescribes indifference only between hypotheses about which observer you are, when you have no information about which of these observers you are. It does not in general prescribe indifference between hypotheses when you lack specific information about which of the hypotheses is true. In contrast to Laplacean and other more ambitious principles of indifference, it is therefore immune to Bertrand’s paradox and similar predicaments that tend to plague indifference principles of unrestricted scope.

Readers familiar with the Doomsday argument may worry that the bland principle of indifference invoked here is the same assumption that is responsible for getting the Doomsday argument off the ground, and that the counterintuitiveness of some of the implications of the latter incriminates or casts doubt on the validity of the former. This is not so. The Doomsday argument rests on a much stronger and more controversial premiss, namely that one should reason as if one were a random sample from the set of all people who will ever have lived (past, present, and future) even though we know that we are living in the early twenty-first century rather than at some point in the distant past or the future. The bland indifference principle, by contrast, applies only to cases where we have no information about which group of people we belong to.

If betting odds provide some guidance to rational belief, it may also be worth to ponder that if everybody were to place a bet on whether they are in a simulation or not, then if people use the bland principle of indifference, and consequently place their money on being in a simulation if they know that that’s where almost all people are, then almost everyone will win their bets. If they bet on not being in a simulation, then almost everyone will lose. It seems better that the bland indifference principle be heeded.

Further, one can consider a sequence of possible situations in which an increasing fraction of all people live in simulations: 98%, 99%, 99.9%, 99.9999%, and so on. As one approaches the limiting case in which everybody is in a simulation (from which one can deductively infer that one is in a simulation oneself), it is plausible to require that the credence one assigns to being in a simulation gradually approach the limiting case of complete certainty in a matching manner.

VI. INTERPRETATION

The possibility represented by proposition (1) is fairly straightforward. If (1) is true, then humankind will almost certainly fail to reach a posthuman level; for virtually no species at our level of development become posthuman, and it is hard to see any justification for thinking that our own species will be especially privileged or protected from future disasters. Conditional on (1), therefore, we must give a high credence to DOOM, the hypothesis that humankind will go extinct before reaching a posthuman level:

One can imagine hypothetical situations were we have such evidence as would trump knowledge of fp. For example, if we discovered that we were about to be hit by a giant meteor, this might suggest that we had been exceptionally unlucky. We could then assign a credence to DOOM larger than our expectation of the fraction of human-level civilizations that fail to reach posthumanity. In the actual case, however, we seem to lack evidence for thinking that we are special in this regard, for better or worse.

Proposition (1) doesn’t by itself imply that we are likely to go extinct soon, only that we are unlikely to reach a posthuman stage. This possibility is compatible with us remaining at, or somewhat above, our current level of technological development for a long time before going extinct. Another way for (1) to be true is if it is likely that technological civilization will collapse. Primitive human societies might then remain on Earth indefinitely.

There are many ways in which humanity could become extinct before reaching posthumanity. Perhaps the most natural interpretation of (1) is that we are likely to go extinct as a result of the development of some powerful but dangerous technology. One candidate is molecular nanotechnology, which in its mature stage would enable the construction of self-replicating nanobots capable of feeding on dirt and organic matter – a kind of mechanical bacteria. Such nanobots, designed for malicious ends, could cause the extinction of all life on our planet.

The second alternative in the simulation argument’s conclusion is that the fraction of posthuman civilizations that are interested in running ancestor-simulation is negligibly small. In order for (2) to be true, there must be a strong convergence among the courses of advanced civilizations. If the number of ancestor-simulations created by the interested civilizations is extremely large, the rarity of such civilizations must be correspondingly extreme. Virtually no posthuman civilizations decide to use their resources to run large numbers of ancestor-simulations. Furthermore, virtually all posthuman civilizations lack individuals who have sufficient resources and interest to run ancestor-simulations; or else they have reliably enforced laws that prevent such individuals from acting on their desires.

What force could bring about such convergence? One can speculate that advanced civilizations all develop along a trajectory that leads to the recognition of an ethical prohibition against running ancestor-simulations because of the suffering that is inflicted on the inhabitants of the simulation. However, from our present point of view, it is not clear that creating a human race is immoral. On the contrary, we tend to view the existence of our race as constituting a great ethical value. Moreover, convergence on an ethical view of the immorality of running ancestor-simulations is not enough: it must be combined with convergence on a civilization-wide social structure that enables activities considered immoral to be effectively banned.Another possible convergence point is that almost all individual posthumans in virtually all posthuman civilizations develop in a direction where they lose their desires to run ancestor-simulations. This would require significant changes to the motivations driving their human predecessors, for there are certainly many humans who would like to run ancestor-simulations if they could afford to do so. But perhaps many of our human desires will be regarded as silly by anyone who becomes a posthuman. Maybe the scientific value of ancestor-simulations to a posthuman civilization is negligible (which is not too implausible given its unfathomable intellectual superiority), and maybe posthumans regard recreational activities as merely a very inefficient way of getting pleasure – which can be obtained much more cheaply by direct stimulation of the brain’s reward centers. One conclusion that follows from (2) is that posthuman societies will be very different from human societies: they will not contain relatively wealthy independent agents who have the full gamut of human-like desires and are free to act on them.

The possibility expressed by alternative (3) is the conceptually most intriguing one. If we are living in a simulation, then the cosmos that we are observing is just a tiny piece of the totality of physical existence. The physics in the universe where the computer is situated that is running the simulation may or may not resemble the physics of the world that we observe. While the world we see is in some sense “real”, it is not located at the fundamental level of reality.

It may be possible for simulated civilizations to become posthuman. They may then run their own ancestor-simulations on powerful computers they build in their simulated universe. Such computers would be “virtual machines”, a familiar concept in computer science. (Java script web-applets, for instance, run on a virtual machine – a simulated computer – inside your desktop.) Virtual machines can be stacked: it’s possible to simulate a machine simulating another machine, and so on, in arbitrarily many steps of iteration. If we do go on to create our own ancestor-simulations, this would be strong evidence against (1) and (2), and we would therefore have to conclude that we live in a simulation. Moreover, we would have to suspect that the posthumans running our simulation are themselves simulated beings; and their creators, in turn, may also be simulated beings.

Reality may thus contain many levels. Even if it is necessary for the hierarchy to bottom out at some stage – the metaphysical status of this claim is somewhat obscure – there may be room for a large number of levels of reality, and the number could be increasing over time. (One consideration that counts against the multi-level hypothesis is that the computational cost for the basement-level simulators would be very great. Simulating even a single posthuman civilization might be prohibitively expensive. If so, then we should expect our simulation to be terminated when we are about to become posthuman.)

Although all the elements of such a system can be naturalistic, even physical, it is possible to draw some loose analogies with religious conceptions of the world. In some ways, the posthumans running a simulation are like gods in relation to the people inhabiting the simulation: the posthumans created the world we see; they are of superior intelligence; they are “omnipotent” in the sense that they can interfere in the workings of our world even in ways that violate its physical laws; and they are “omniscient” in the sense that they can monitor everything that happens. However, all the demigods except those at the fundamental level of reality are subject to sanctions by the more powerful gods living at lower levels.

Further rumination on these themes could climax in a naturalistic theogony that would study the structure of this hierarchy, and the constraints imposed on its inhabitants by the possibility that their actions on their own level may affect the treatment they receive from dwellers of deeper levels. For example, if nobody can be sure that they are at the basement-level, then everybody would have to consider the possibility that their actions will be rewarded or punished, based perhaps on moral criteria, by their simulators. An afterlife would be a real possibility. Because of this fundamental uncertainty, even the basement civilization may have a reason to behave ethically. The fact that it has such a reason for moral behavior would of course add to everybody else’s reason for behaving morally, and so on, in truly virtuous circle. One might get a kind of universal ethical imperative, which it would be in everybody’s self-interest to obey, as it were “from nowhere”.

In addition to ancestor-simulations, one may also consider the possibility of more selective simulations that include only a small group of humans or a single individual. The rest of humanity would then be zombies or “shadow-people” – humans simulated only at a level sufficient for the fully simulated people not to notice anything suspicious. It is not clear how much cheaper shadow-people would be to simulate than real people. It is not even obvious that it is possible for an entity to behave indistinguishably from a real human and yet lack conscious experience. Even if there are such selective simulations, you should not think that you are in one of them unless you think they are much more numerous than complete simulations. There would have to be about 100 billion times as many “me-simulations” (simulations of the life of only a single mind) as there are ancestor-simulations in order for most simulated persons to be in me-simulations.

There is also the possibility of simulators abridging certain parts of the mental lives of simulated beings and giving them false memories of the sort of experiences that they would typically have had during the omitted interval. If so, one can consider the following (farfetched) solution to the problem of evil: that there is no suffering in the world and all memories of suffering are illusions. Of course, this hypothesis can be seriously entertained only at those times when you are not currently suffering.

Supposing we live in a simulation, what are the implications for us humans? The foregoing remarks notwithstanding, the implications are not all that radical. Our best guide to how our posthuman creators have chosen to set up our world is the standard empirical study of the universe we see. The revisions to most parts of our belief networks would be rather slight and subtle – in proportion to our lack of confidence in our ability to understand the ways of posthumans. Properly understood, therefore, the truth of (3) should have no tendency to make us “go crazy” or to prevent us from going about our business and making plans and predictions for tomorrow. The chief empirical importance of (3) at the current time seems to lie in its role in the tripartite conclusion established above. We may hope that (3) is true since that would decrease the probability of (1), although if computational constraints make it likely that simulators would terminate a simulation before it reaches a posthuman level, then out best hope would be that (2) is true.

If we learn more about posthuman motivations and resource constraints, maybe as a result of developing towards becoming posthumans ourselves, then the hypothesis that we are simulated will come to have a much richer set of empirical implications.

VII. CONCLUSION

A technologically mature “posthuman” civilization would have enormous computing power. Based on this empirical fact, the simulation argument shows that at least one of the following propositions is true: (1) The fraction of human-level civilizations that reach a posthuman stage is very close to zero; (2) The fraction of posthuman civilizations that are interested in running ancestor-simulations is very close to zero; (3) The fraction of all people with our kind of experiences that are living in a simulation is very close to one.

If (1) is true, then we will almost certainly go extinct before reaching posthumanity. If (2) is true, then there must be a strong convergence among the courses of advanced civilizations so that virtually none contains any relatively wealthy individuals who desire to run ancestor-simulations and are free to do so. If (3) is true, then we almost certainly live in a simulation. In the dark forest of our current ignorance, it seems sensible to apportion one’s credence roughly evenly between (1), (2), and (3).

Unless we are now living in a simulation, our descendants will almost certainly never run an ancestor-simulation.

From: http://www.simulation-argument.com/simulation.html

DOUGLAS HOFSTADTER

GÖDEL, ESCHER, BACH

Gödel, Escher, Bach: An Eternal Golden Braid (commonly GEB) is a Pulitzer Prize-winning book by Douglas Hofstadter, described as "a metaphorical fugue on minds and machines in the spirit of Lewis Carroll”.

On its surface, GEB examines logician Kurt Gödel, artist M. C. Escher and composer Johann Sebastian Bach, discussing common themes in their work and lives. At a deeper level, the book is a detailed and subtle exposition of concepts fundamental to mathematics, symmetry, and intelligence.

Through illustration and analysis, the book discusses how self-reference and formal rules allow systems to acquire meaning despite being made of "meaningless" elements. It also discusses what it means to communicate, how knowledge can be represented and stored, the methods and limitations of symbolic representation, and even the fundamental notion of "meaning" itself.

In response to confusion over the book´s theme, Hofstadter has emphasized that GEB is not about mathematics, art, and music but rather about how cognition and thinking emerge from well-hidden neurological mechanisms. In the book, he presents an analogy about how the individual neurons of the brain coordinate to create a unified sense of a coherent mind by comparing it to the social organization displayed in a colony of ants.

STRUCTURE

GEB takes the form of an interweaving of various narratives. The main chapters alternate with dialogues between imaginary characters, inspired by Lewis Carroll's "What the Tortoise Said to Achilles", in which Achilles and the Tortoise discuss a paradox related to modus ponens. Hofstadter bases the other dialogues on this one, introducing characters such as a Crab, a Genie, and others. These narratives frequently dip into self-reference and metafiction.

Word play also features prominently in the work. Puns are occasionally used to connect ideas, such as "the Magnificrab, Indeed" with Bach's Magnificat in D; " SHRDLU, Toy of Man's Designing" with Bach's Jesu, Joy of Man´s Desiring; and "Typographical Number Theory", or "TNT", which inevitably reacts explosively when it attempts to make statements about itself. One Dialogue contains a story about a genie (from the Arabic "Djinn") and various "tonics" (of both the liquid and musical varieties), which is of course entitled "Djinn and Tonic".

One dialogue in the book is written in the form of a crab canon, in which every line before the midpoint corresponds to an identical line past the midpoint. The conversation still makes sense due to uses of common phrases which can be used as either greetings or farewells ("Good day") and the positioning of lines which, upon close inspection, double as an answer to a question in the next line.

THEMES

GEB contains many instances where objects and ideas speak about or refer back to themselves (cf. recursion and self-reference). For instance, TNT is an illustration of Gödel´s incompleteness theorem. There is also a phonograph which destroys itself by playing a record entitled "I Cannot Be Played on Record Player X" (this being an analogy to Gödel's incompleteness theorem), an examination of canon form in music, and a discussion of Escher's lithograph of two hands drawing each other. To describe such self-referencing objects, Hofstadter coins the term "strange loop", a concept he examines in more depth in his follow-up book I Am a Strange Loop.

To escape many of the logical contradictions brought about by these self-referencing objects, Hofstadter discusses Zen Koans. He attempts to show the reader how to perceive reality outside the normal confines of their own experience and embrace such paradoxical questions by rejecting the premise — a strategy also called “unasking”.

Call stacks are also discussed in GEB, as one dialogue describes the adventures of Achilles and the Tortoise as they make use of "pushing" and "popping" tonics. Entering a picture in a book would count as "pushing", entering a picture in a book within a picture in a book would have caused a double "pushing", and "popping" refers to an exit back to the previous layer of reality. The Tortoise humorously remarks that a friend of his (a weasel) performed a "popping" while in their current state of reality and has never been heard from since; the implied question is, "Did the friend simply cease to exist, or has the friend achieved a higher state of reality?" Also, since the reader is "pushed" into the world of Tortoise and Achilles, would the friend have ascended to the same level of reality in which the readers of GEB reside? Subsequent sections discuss the basic tenets of logic, self-referring statements, ("typeless") systems, and even programming.

One puzzle (in the dialogue "Aria with Diverse Variations") is a speculation concerning an author who writes a book and chooses to end the story without actually stopping the text. That an author cannot make a sudden ending (with regard to the story) come as a surprise, when the fact that there are only a few pages left in the book is obvious to the reader. Such an author might wrap up the main point, and then continue writing, but drop clues to the reader that the end has already passed, such as wandering and unfocused prose, misstatements, or contradictions.

PUZZLES

The book is filled with puzzles. An example of this is the chapter entitled "Contracrostipunctus", which combines the words acrostic and contrapunctus (counterpoint). In a dialogue between Achilles and the Tortoise, the author hints that there is a contrapuntal acrostic in the chapter that refers both to the author (Hofstadter) and Bach. This can be found by taking the first word of each paragraph, to reveal: Hofstadter's Contracrostipunctus Acrostically Backwards Spells "J. S. Bach". This is only the acrostic. The counterpoint acrostic is found by taking the first letters of the acrostic (in bold) and reading them backwards to get "J. S. Bach" (as the acrostic itself claims).

Art of fugue(Contrapunctus XIV)

TRANSLATION

Although Hofstadter claims the idea of translating his book "never crossed [his] mind" when he was writing it, when approached with the idea by his publisher he was "very excited about seeing [the] book in other languages, especially … French". He knew, however, that "there were a million issues to consider" when translating, since the book relies not only on word-play but "structural puns" as well—writing where the form and content of the work mirror each other (such as the "Crab Canon" dialogue, which reads almost exactly the same forwards as backwards).

Hofstadter gives one example of translation trouble in the paragraph "Mr. Tortoise, Meet Madame Tortue", saying translators "instantly ran headlong into the conflict between the feminine gender of the French noun tortue and the masculinity of my character, the Tortoise". Hofstadter decided to translate the French character as "Madame Tortue", and the Italian version as "signorina Tartaruga". Because of other troubles translators might have retaining the meaning of the book, Hofstadter "painstakingly went through every last sentence of GEB, annotating a copy for translators into any language that might be targeted".

Translation also gave Hofstadter a way to add new meaning and puns. For instance, in Chinese, the subtitle is not a translation of an Eternal Golden Braid, but a seemingly unrelated phrase Jí Yì Bì (集异璧, literally "collection of exotic jades") which is homophonic to GEB in Chinese. Some material regarding this interplay is to be found in Hofstadter's later book Le Ton beau de marot, which is mainly about translation.

BlooP and FlooP

BLooP and FLooP are simple programming languages designed by Douglas Hofstadter to illustrate a point in his book Gödel, Escher, Bach. BLooP is a non-Turing-complete programming language whose only control flow structure is a bounded loop. This language can only express primitive recursive functions. FLooP is identical except that it supports unbounded loops; it is a Turing-complete language. These can be regarded as primitive models of computation.

BLooP examples

Note: The only variables are output (the return value of the procedure) and cell(i) (an infinite array of integers). The only operators are ⇐ (assignment), + (addition), × (multiplication), < (less-than), > (greater-than) and = (equals).

Factorial function:

Subtraction function (this is not a built-in operation):

From Wikipedia

Henry Markram

BLUE BRAIN PROJECT

Henry Markram, Project Director of the Blue Brain Project, Director of the Center for Neuroscience & Technology and co-Director of EPFL's Brain Mind Institute, obtained his B.Sc. (Hons) from Cape Town University, South Africa under the supervision of Rodney Douglas and his Ph.D from the Weizmann Institute of Science, Israel, under the supervision of Menahem Segal. During his PhD he discovered a link between acetylcholine and memory mechanisms by showing that acetylcholine modulates the primary receptor linked to synaptic plasticity.

He went to the USA as a Fulbright Scholar at the National Institutes of Health (NIH), where he studied ion channels on synaptic vesicles. He then went as a Minerva Fellow to the Laboratory of Bert Sakmann at the Max Planck Institute, Heidelberg, Germany, where he discovered calcium transients in dendrites evoked by sub-threshold activity, and by single action potentials propagating back into dendrites. He also began studying the connectivity between neurons, describing in great detail how layer 5 pyramidal neurons are interconnected.

He was the first to alter the precise millisecond relative timing of single pre- and post-synaptic action potentials to reveal a highly precise learning mechanism operating between neurons -- now reproduced in many brain regions and known as spike timing-dependent synaptic plasticity (STDP). These experiments were carried out in 1993, four years before publication. Although there were some correlation-sensitive findings before, this was the first study that manipulated single pre- and post-synaptic spike times to monitor the effect of synaptic changes.

He was appointed assistant professor at the Weizmann Institute for Science, Israel, where he started systematically dissecting out the neocortical column. He discovered that synaptic learning can also involve a change in synaptic dynamics (called redistribution of synaptic efficacy) rather than merely changing the strengths of connections. He also revealed a spectrum of new principles governing neocortical microcircuit structure, function, and emergent dynamics. Based on the emergent dynamics of the neocortical microcircuit he and Wolfgang Maass developed the theory of liquid computing, or high entropy computing.

In 2002 he moved to EPFL as full professor and founder/director of the Brain Mind Institute and Director of the Center for Neuroscience and Technology. At the BMI, in the Laboratory for Neural Microcircuitry, Markram has continued to unravel the blueprint of the neocortical column, building state-of-the-art tools to carry out multi-neuron patch clamp recordings combined with laser and electrical stimulation as well as multi-site electrical recording ,chemical imaging and gene expression. Markram has received numerous awards and published over 75 papers.

About the Blue Brain Project

The cerebral cortex, the convoluted "grey matter" that makes up 80% of the human brain, is responsible for our ability to remember, think, reflect, empathize, communicate, adapt to new situations and plan for the future. The cortex first appeared in mammals, and it has a fundamentally simple repetitive structure that is the same across all mammalian species.



The brain is populated with billions of neurons, each connected to thousands of its neighbors by dendrites and axons, a kind of biological "wiring". The brain processes information by sending electrical signals from neuron to neuron along these wires. In the cortex, neurons are organized into basic functional units, cylindrical volumes 0.5 mm wide by 2 mm high, each containing about 10,000 neurons that are connected in an intricate but consistent way. These units operate much like microcircuits in a computer. This microcircuit, known as the neocortical column (NCC), is repeated millions of times across the cortex. The difference between the brain of a mouse and the brain of a human is basically just volume - humans have many more neocortical columns and thus neurons than mice.

This structure lends itself to a systematic modeling approach. And indeed, the first step of the Blue Brain project is to re-create this fundamental microcircuit, down to the level of biologically accurate individual neurons. The microcircuit can then be used in simulations.

What the Blue Brain Project is not

The Blue Brain Project is an attempt to reverse engineer the brain, to explore how it functions and to serve as a tool for neuroscientists and medical researchers. It is not an attempt to create a brain. It is not an artificial intelligence project. Although we may one day achieve insights into the basic nature of intelligence and consciousness using this tool, the Blue Brain Project is focused on creating a physiological simulation for biomedical applications.

Building the microcircuit


Modeling Neurons

Neurons are not all alike - they come in a variety of complex shapes. The precise shape and structure of a neuron influences its electrical properties and connectivity with other neurons. A neuron's electrical properties are determined to a large extent by a variety of ion channels distributed in varying densities throughout the cell's membrane. Scientists have been collecting data on neuron morphology and electrical behavior of the juvenile rat in the laboratory for many years, and this data is used as the basis for a model that is run on the Blue Gene to recreate each of the 10,000 neurons in the NCC.

Modeling connections

To model the neocortical column, it is essential to understand the composition, density and distribution of the numerous cortical cell types. Each class of cells is present in specific layers of the column. The precise density of each cell type and the volume of the space it occupies provides essential information for cell positioning and constructing the foundation of the cortical circuit. Each neuron is connected to thousands of its neighbors at points where their dendrites or axons touch, known as synapses. In a column with 10,000 neurons, this translates into trillions of possible connections. The Blue Gene is used in this extremely computationally intensive calculation to fix the synapse locations, "jiggling" individual neurons in 3D space to find the optimal connection scenario.

Modeling the column

The result of all these calculations is a re-creation, at the cellular level, of the neocortical column, the basic microcircuit of the brain. In this case, it's the cortical column of a juvenile rat. This is the only biologically accurate replica to date of the NCC - the neurons are biologically realistic and their connectivity is optimized. This would be impossible without the huge computational capacity of the Blue Gene. A model of the NCC was completed at the end of 2006.
In November, 2007, The Blue Brain Project officially announced the conclusion of Phase I of the project, with three specific acheivements:

1. A new modeling framework for automatic, on-demand construction of neural circuits built from biological data

2. A new simulation and calibration process that automatically and systematically analyzes the biological accuracy and consistency of each revision of the model

3. The first cellular-level neocortical column model built entirely from biological data that can now serve as a key tool for simulation-based research

Simulating the microcircuit



Once the microcircuit is built, the exciting work of making the circuit function can begin. All the 8192 processors of the Blue Gene are pressed into service, in a massively parallel computation solving the complex mathematical equations that govern the electrical activity in each neuron when a stimulus is applied. As the electrical impulse travels from neuron to neuron, the results are communicated via inter-processor communication (MPI). Currently, the time required to simulate the circuit is about two orders of magnitude larger than the actual biological time simulated. The Blue Brain team is working to streamline the computation so that the circuit can function in real time - meaning that 1 second of activity can be modeled in one second.

Interpreting the results

Running the Blue Brain simulation generates huge amounts of data. Analyses of individual neurons must be repeated thousands of times. And analyses dealing with the network activity must deal with data that easily reaches hundreds of gigabytes per second of simulation. Using massively parallel computers the data can be analyzed where it is created (server-side analysis for experimental data, online analysis during simulation).

Given the geometric complexity of the column, a visual exploration of the circuit is an important part of the analysis. Mapping the simulation data onto the morphology is invaluable for an immediate verification of single cell activity as well as network phenomena. Architects at EPFL have worked with the Blue Brain developers to design a visualization interface that translates the Blue Gene data into a 3D visual representation of the column. A different supercomputer is used for this computationally intensive task. The visualization of the neurons' shapes is a challenging task given the fact that a column of 10,000 neurons rendered in high quality mesh (see picture) accounts for essentially 1 billion triangles for which about 100GB of management data is required. Simulation data with a resolution of electrical compartments for each neuron accounts for another 150GB. As the electrical impulse travels through the column, neurons light up and change color as they become electrically active. See some clips of the column in action.

A visual interface makes it possible to quickly identify areas of interest that can then be studied more extensively using further simulations. A visual representation can also be used to compare the simulation results with experiments that show electrical activity in the brain. This calibration - comparing the functioning of the Blue Brain circuit with experiment, improving and fine-tuning it - is the second stage of the Blue Brain project, expected to be complete by the end of 2007.

What's next for the Blue Brain Project?

Phase I marks the completion of a proof-of-principle simulation-based research process that has resulted in a cellular-level model of the neocortical column. We have achieved biological fidelity such that the model itself now serves as a primary tool for evaluating the consistency and relevance of neurobiological data, while providing guidance for new experimental efforts. These new data will serve to further refine the neocortical column model. The assembled process allows neuroscientists to investigate scientific questions by integrating the available experimental data and evaluating hypotheses of network dynamics and neural function.

The completion of phase I provides the basis now for increasing the resolution of the models down to the molecular level and expanding the size of the models towards the whole brains of mammals.

In the future, information from the molecular and genetic level will be added to the algorithms that generate the individual neurons and their connections, and thus this level of detail will be reflected in the circuit's construction. The simulations can be used to explore what happens when this molecular or genetic information is altered -- situations such as a genetic variation in particular neurotransmitters, or what happens when the molecular environment is altered via drugs.

The project will continue to expand and will necessarily involve additional scientists and research groups from around the world.

http://bluebrain.epfl.ch/page18699.html

Hans Moravec

SUPERHUMANISM


Hans Moravec (born November 30, 1948 in Austria) is an adjunct faculty member at the Robotics Institute (Carnegie Mellon) of Carnegie Mellon University. He is known for his work on robotics, artificial intelligence, and writings on the impact of technology. Moravec also is a futurist with many of his publications and predictions focusing on transhumanism. Moravec developed techniques in computer vision for determining the region of interest (ROI) in a scene. Other ROI techniques exist, including the patents of Sherman de Forest (U.S.), and the computer vision / image processing articles by Sobel. His last academic publication was in 2003.

From Wikipedia

According to Hans Moravec, by 2040 robots will become as smart as we are. And then they'll displace us as the dominant form of life on Earth. But he isn't worried - the robots will love us.
By Charles Platt
Hans Moravec reclines in his chair and places his palms against his chest. "Consider the human form," he says.
"It clearly isn't designed to be a scientist. Your mental capacity is extremely limited. You have to undergo all kinds of unnatural training to get your brain even half suited for this kind of work - and for that reason, it's hard work. You live just long enough to start figuring things out before your brain starts deteriorating. And then, you die."
He leans forward, and his eyes widen with enthusiasm. "But wouldn't it be great," he says, "if you could enhance your abilities via artificial intelligence, and extend your lifespan, and improve on the human condition?"
Since his earliest childhood, Moravec has been obsessed with artificial life. When he was 4 years old, his father helped him use a wooden erector set to build a model of a little man who would dance and wave his arms and legs when a crank was turned. "It excited me," says Moravec, "because at that moment, I saw you could assemble a few parts and end up with something more - it could seem to have a life of its own."
At the age of 10, he constructed a toy robot from miscellaneous scrap metal. In high school, when another student maintained that no machine could ever be truly human, Moravec suggested replacing human neurons, one at a time, using man-made components that would have the equivalent function. At what point, he asked, would humanness disappear? If a wholly artificial entity is still able to act human in every way, how could we prove that it isn't human?
Today, Moravec is a professor at Carnegie Mellon University's Robotics Institute, the largest robot research lab in the country and one he helped establish in 1980. He is a rare mixture of visionary and engineer, equally comfortable speculating on the fate of the planet or using a soldering iron, microchips, and stepper motors to build high-tech versions of his childhood dancing man. More than that, though, he's our most gung-ho advocate of technology as a tool to transform human beings and make us more than we are - within our lifetimes, if we want it.
Some of his concepts have a confrontational, in-your-face shock value. For instance, to find out how the mind works, Moravec suggests severing a volunteer's corpus callosum (the nerve bundle linking the two hemispheres of the human brain) and interposing a computer to monitor thought traffic. After the computer has had time to learn the code, it can start inserting its own input, helping solve difficult math problems, suggesting new ideas, even offering friendly advice.
Or here's another scenario for anyone who'd like to escape the constrictions of dull old human biology: a futuristic robot surgeon peels away the brain of a conscious patient, using sensors to analyze and simulate the function of every neuron in each slice. As Moravec puts it, "Eventually your skull is empty, and the surgeon's hand rests deep in your brainstem. Though you haven't lost consciousness, your mind has been removed from the brain and transferred to a machine."
But even proposals like these are modest compared with Moravec's Number One concern, which is nothing less than the future of humanity. By 2040, he believes, we can have robots that are as smart as we are. Eventually, these machines will begin their own process of evolution and render us extinct in our present form. Yet, according to Moravec, this is not something we should fear: it's the best thing we could hope for, the ultimate form of human transcendence. And in his own laboratory, he's laying the groundwork that may help this evolutionary leap happen ahead of schedule.
Not everyone thinks this is such a wonderful idea. Joseph Weizenbaum, professor emeritus of computer science at MIT, complains that Moravec's book Mind Children: The Future of Robot and Human Intelligence is as dangerous as Mein Kampf. Respected mathematician Roger Penrose has written a long essay for The New York Review of Books in which he twice uses the word "horrific" to describe some of Moravec's concepts. Book reviewer Poovan Murugesan denounces Moravec as "a loose cannon of fast ideas" who suffers from "irresponsible optimism."
Even Moravec's fans seem a little ambivalent. "He comes off as a cross between Mister Rogers and Dr. Faustus," says writer Richard Kadrey. And in the words of award-winning science fiction author Vernor Vinge, who is also an associate professor of mathematical sciences at San Diego State University, "Moravec puts the rest of the technological optimists to shame. He is beyond their wildest extremes." But, Vinge adds hastily, "I mean this as praise!"
How seriously should we take Moravec's ideas? He is widely respected as a pioneer in robotics, but where is the line dividing his painstakingly practical research from his unfettered speculation? Why does he insist that breaking the boundaries of being human is important not just for himself, but for everyone - and why does he seem so crazy-cheerful about the whole thing?
These questions were on my mind when I visited Moravec at Carnegie Mellon in Pittsburgh, Pennsylvania. In person, he's a friendly faced, slightly overweight, irrepressibly good-humored man in his late 40s who wears homely clothes and seems shy with strangers. But his enthusiasm gives him a childlike charm - even when he talks lyrically about human extinction.
His office is next door to the "high bay," a big lab displaying the results of previous Robotics Institute projects, including a huge, multilegged "walker" that was sent down into the cone of an active volcano, and a Pontiac minivan that can drive itself at speeds up to 60 mph. The van has already found its way from Pittsburgh to Washington, DC, with minimal human supervision, under the legal fiction that its four onboard Sparcstations and their mechanical interface are "an advanced form of cruise control."
But Moravec seems bored by these past achievements and has shed most of his administrative responsibilities at the Robotics Institute. He hides out in a small, undistinguished, modern office with a couple of computers, a few file cabinets, a refrigerator, a microwave oven, and a lot of books. This is where he pursues his immediate goal: designing and programming a domestic robot that can navigate freely in cluttered home environments. It is the next logical step, he says, toward truly intelligent machines that we will not only tolerate but love - even as they threaten to displace us as the dominant form of life on Earth.
Moravec's early work in robotics was plagued by setbacks. "I spent most of the 1970s," he recalls, "trying to teach a robot to find its way across a room. After 10 years, in 1979, I finally had one that could get where it was going three times out of four - but it took five hours to travel 90 feet." He chuckles like a fond father recalling the first incompetent steps of his baby boy.
Why was it so hard for a robot to accomplish a task that even a mouse can manage with ease? The answer, of course, is that animals have had hundreds of millions of years in which to evolve motor skills. The problem of moving through a three-dimensional world is hideously complex, as Moravec indicates, while counting off the tasks on his fingers: "Our robot used multiple images of the same scene, taken from different points of view, in order to infer distance and construct a sparse description of its surroundings. It used statistical methods to resolve mismatching errors. It planned obstacle-avoidance paths. And then it had to decide how to actually turn its motors and wheels."
In 1980, he built new robots and attempted to boost their performance. "But the best we were able to do with our old approach," he recounts, "was speed it up about tenfold and improve its accuracy tenfold. We did not manage to reduce its brittleness."
By "brittleness" Moravec means that the system tended to fail suddenly and catastrophically. "Accidental conspiracies of sensory miscues would lead it to a wrong conclusion while being sure that it was right. In practical terms, it could misidentify the surrounding objects and run into a wall."
Like Wile E. Coyote in a Road Runner cartoon, trying to run into the mouth of a tunnel painted on a rockface?
"Precisely!" he laughs again, sounding genuinely happy, as he does whenever he describes the lovably fallible behavior of his creations.
In 1984, using US$10 Polaroid ultrasonic range finders instead of expensive video cameras, he created a new commercial robot that analyzed maps of the surrounding space rather than just objects in it. The result, to his surprise, was a system that could navigate reliably and relatively swiftly.
Moravec's current research robot, a project initiated in 1987, now sits in a small workshop just across the corridor outside his office. "Would you like to take a look?" he asks.
We walk into a windowless space no larger than an average living room. There are a couple of video monitors, workbenches littered with tools, pale beige walls, and a vinyl floor. The robot stands in the center of the room: an ugly little four-wheeled truck the size of a go-cart. But Moravec exudes pleasure and affection as he guides his toy out of the workshop, into the hall, and back again.
Today's best robots can think at insect level," he says as we return to his office. He explains that state-of-the-art mobile robots orient themselves by sensing special markers placed on floors, walls, or ceilings. Insects behave the same way: ants follow pheromone trails, lightning bugs look for each other's flashes, and moths navigate with reference to the moon.
The trouble is, such systems are still brittle. Just as a moth can become fatally confused by fixing on candlelight instead of moonlight, a robot guided by markers can easily make a disastrous mistake - as happened when one designed by a Connecticut company to distribute hospital linens took a nosedive down a flight of stairs when it failed to notice a marker that was supposed to tell it not to proceed past a certain point.
Robots that orient themselves with markers have found some application in industry - transporting pallets and cleaning floors - but they offer few advantages over the older systems that follow hidden guide wires. As a result, the market is very limited. "In fact," says Moravec, "the market barely exists at all. So, what we're shooting at now is a robot with the intelligence of a small vertebrate - the smallest fish you can imagine. It will no longer depend on navigational points; it will build a relatively dense representation of volumes of space."
By 2000, he foresees that this type of machine will find its own way around complex, cluttered places without using markers and without needing to be installed by experts. At first these robots will be expensive and specialized, but Moravec predicts they will become smaller, cheaper, and more user-friendly in just the same way that microcomputers evolved from mainframes. "Once we have a robot that customers can take out of the box, show it a job, and trust it to work without doing silly things - then the market will grow easily to hundreds of thousands and beyond. Any institution that does regular cleaning will find that it's cheaper to use a robot than a person. The same goes for delivery jobs."
Moravec estimates that these systems will need an onboard computer capable of 500 million instructions per second. The first IBM PCs managed 0.3 mips; a modern Pentium-based PC reaches 200 mips; and it's reasonable to expect that 500-mips processors will be affordable by the turn of the century.
This power will enable the robot to convert 500-by-500-pixel stereoscopic pictures from its camera eyes into a 3-D model consisting of about 100-by-100-by-100 cells. Updating and processing all this visual information will take about one second - the longest interval that is reasonably safe and practical, since the robot will move blindly between glimpses of the world.
Once robots find a niche doing dull, repetitive jobs, Moravec sees an ever-expanding market. "The next step will be adding an arm and improving the sensor resolution so that they can find and manipulate objects. The result will be a first generation of universal robots, around 2010, with enough general competence to do relatively intricate mechanical tasks such as automotive repair, bathroom cleaning, or factory assembly work."
By "universal" Moravec means the robot will tackle many different jobs in the same way a Nintendo system plays many different games. Plug in one cartridge, and the robot will know how to change the oil in your car. Plug in another, and it will know how to patrol your property and challenge intruders.
Add more memory and computing power and enhance the software, and by 2020 we have a second generation that can learn from its own performance. "It will tackle tasks in various ways," says Moravec, "keep statistics on how well each alternative has succeeded, and choose the approach that worked best. This means that it can learn and adapt. Success or failure will be defined by separate programs that will monitor the robot's actions and generate internal punishment and reward signals, which will actually shape its character - what it likes to do and what it prefers not to do."
Moravec pauses. The near future of robotics is something he's spelled out a thousand times before, and he no longer finds it particularly exciting. But now we get to a subject that interests him more: the idea that robots can mimic human traits.
By 2030, according to Moravec, we should have a third-generation universal robot that emulates higher-level thought processes such as planning and foresight. "It will maintain an internal model not only of its own past actions, but of the outside world," he explains. "This means it can run different simulations of how it plans to tackle a task, see how well each one works out, and compare them with what it's done before." An onlooker will have the eerie sense that it's imagining different solutions to a problem, developing its own ideas.
But perfecting the model of reality this robot will need is not going to be an easy task. In fact, creating this model is the single hardest problem in artificial intelligence. Intuitively, human beings know why they need to wear a raincoat in wet weather, or why they must turn the handle before pushing open a door. Almost without thinking we know if a bottle is empty, whether an object is breakable, or when food has spoiled. But to an artificial intelligence, none of these things is obvious - each everyday fact must be established in advance or derived from logical principles.
On the plus side, each time a robot learns a fact or masters a skill, it will be able to pass its knowledge to other robots as quickly and easily as sending a program over the Net. This way, the task of understanding the world can be divided among thousands or millions of robot minds. As a result, the machines will soon develop a deeper knowledge base than any single person can hope to possess. Within a short space of time, robots that are linked in this way will no longer need our help to show them how to do anything.
Meanwhile, they will be smart enough to interact with us on a human level. "Their world model will include psychological attributes," Moravec says, "which means, for instance, that a robot will express in its internal language a logical statement such as 'I must be careful with this item, because it is valuable to my owner, and if I break it, my owner will be angry.' This means that if the robot's internal processes are translated into human terms, you will hear a description of consciousness - especially if the robot applies psychological attributes to its own actions, as in 'I don't like to bump into things,' which is a compact way of saying that the robot gets an internal negative reinforcement signal whenever it collides with something, or imagines a collision."
Moravec's critics are skeptical on this point. Many have stated flat out that a machine can never be "conscious." Their arguments are hard to refute, partly because no one can really say what consciousness is; but Moravec sidesteps the issue. He believes a robot that understands human behavior can be programmed to act as if it is conscious, and can also claim to be conscious. If it says it's conscious, and it seems conscious, how can we prove that it isn't conscious?
Either way, there's no doubt that systems that can analyze their world, deduce generalizations, and modify their behavior will have a major impact on society.
"The robots will still be in our thrall," Moravec points out, meaning that we will still be designing and programming them to serve and obey us. "They'll learn everything they know from us, and their goals and their methods will be imitations of ours. But as they become more competent, efficiency and productivity will keep going up, and the amount of work for humans will keep going down. By around 2040, there will be no job that people can do better than robots."
He sits back in his chair, pausing with cheerful satisfaction as he does whenever he reaches a radical conclusion that places him one step ahead, waiting for his audience to catch up.
In this case, though, Moravec's conclusion is less radical than it seems - because when many jobs are broken down into tasks, they require a relatively limited degree of "humanness." Even today, we have expert systems that offer advice based on a large number of facts in a field such as medicine or geology. Imagine this expertise gradually broadening to include subjects such as corporate law, mechanical design, profitability, and efficiency. Decisions in these areas are all made logically from sets of facts, which means that if the facts are completely spelled out, a machine intelligence should be able to deal with them.
Thus a corporation can literally become automated from the bottom up: first the assembly lines, then bookkeeping, product design, and planning. Even management can be taken over by computers that are able to learn from past performance. Ultimately, a corporation will consist of a diverse mix of robots, some mobile, some fixed, some large and powerful, some microscopic, all interacting with speed and versatility that is completely beyond human abilities.
But what about the time scale? Isn't he compressing a huge amount of progress into a very few decades?
"Back in the 1970s I made some overoptimistic assumptions about the rate of progress of computers. I thought that using an array of cheap microcomputers, we might achieve human equivalence by the mid-1980s. Then I did a slightly more careful calculation around 1978 and decided it would take another 20 years, requiring a supercomputer. But then I started getting serious, writing articles and essays, and I thought I should do the calculations more rigorously. So I collected 100 data points of previous computer progress, I did the best calculation I could, I compared the human retina with computer vision applications, and I plotted it all out."
Still, even if his predictions are confirmed to be on schedule, there's an obvious problem: When robots are doing all the work, no one will earn any money. How can an economy flourish when all the consumers are penniless?
Moravec obviously isn't troubled by the question. In fact, it's hard to imagine any question bothering him: he sits calmly, comfortably, eating the questions and spitting out answers with ease. Today, he points out, people who retire are supported via wealth that is ultimately created by industry. As industry becomes more efficient, there will be more wealth, allowing people to retire earlier. When industry is totally automated and hyper-efficient, it will create so much wealth that retirement can begin at birth. "We'll levy a tax on corporations," Moravec says, "and distribute the money to everyone as lifetime social-security payments."
But what if the robot-run corporations fail to function as he expects? He assumes these business entities will follow programs written by us, compelling them to obey laws and pay their taxes. But the programming will also encourage robot-controlled corporations to compete with each other.
Won't they try to exploit loopholes in their instructions, just as present-day businesses try to evade federal regulations? Isn't there a real risk that autonomous robots will steal from each other and cheat on their taxes?
"There is always the possibility that some kind of malfunction will produce a rogue corporation," Moravec admits. "We'll need police provisions so that legal companies will act to suppress rogues economically, or physically, if necessary. And among the inprogrammed laws we'll need antitrust clauses to force dangerously large companies to divest into smaller entities."
But this would be a second set of rules to solve a problem created by robots breaking the first set of rules. The system still seems fundamentally unstable.
"It is unstable," he agrees. "Everything will depend on the way in which we create it. Crafting these machines and the corporate laws that control them is going to be the most important thing humanity ever does. You know, each age has an activity in which the best minds get involved. Crafting the laws, and their implementation, will be the thing to do in the 21st century."
If the job is done right, he predicts a world of comfort, health, and boundless plenty - at least for a while. Human beings will be like slave owners whose servants never complain, need no supervision, and are constantly eager to please.
In the long term, though, robots programmed to serve us with maximum efficiency can become a potential hazard. They will naturally try to obtain energy and raw materials as cheaply as possible, with a minimum of regulatory interference. And the ideal way to do this is by relocating some of their operations beyond planet Earth.
Unlike human beings, robots don't need to breathe air, aren't disoriented by zero gravity, and can be easily shielded from harmful radiation. There are vast mineral resources in the asteroid belt, where there will be no regulations regarding pollution, noise, or safety. Robot factories located in space would be able to manufacture products with maximum efficiency and then drop them down into Earth's gravity well. Alternatively, they could conduct hazardous research and radio the encrypted results back to their parent corporation on Earth.
Only a small "seed colony" of robots would be needed to set up an off-world operation. Using local mineral ores and solar energy, robots could build everything they required - including copies of themselves.
In this scenario, everything is still being controlled by the parent corporations, which are still being controlled by us. Therefore, the off-world operations should present no problems. "But now suppose a company goes out of business," Moravec says, "leaving its research division in space, where there's no supervision. The result is self-sustaining, superintelligent wildlife."
His critics, of course, disagree. They complain that his vision is inhuman, lacking attributes such as culture and art that seem central to our identity. Skeptics also point out that the negative implications of his work far outweigh its benefits in the near future, when robots will cause a huge economic dislocation, creating a feeling of purposelessness among citizens who are rendered permanently unemployable.
Moravec is quite aware of this but sees no way to prevent it. He says his projection of the future is at least 50 percent probable, and we're seeing the first signs of it right now. "In Europe generally," he says, "I believe unemployment is now up to around 15 percent, and essentially this will never reverse. We're already moving into the mode I envisage, where everyone is subsidized by productive machines."
This has created uncertainty and discontent - as he readily admits. "We all agree," he says, "that the world is a bit screwed up. The reason for this is rather obvious. We have a Stone Age brain, but we don't live in the Stone Age anymore. We were fitted by evolution to live in tribal villages of up to 200 relatives and friends, finding and hunting our food. We now live in cities of millions of strangers, supporting ourselves with unnatural tasks we have to be trained to accomplish, like animals who have been forced to learn circus tricks."
In which case, what's the answer? Moravec adamantly believes that reversing the evolution of technology would create an even bigger disaster. "Most of us would starve," he says. He suggests the opposite approach: that we try to catch up with technology by accelerating our own evolution. "We can change ourselves," he says, "and we can also build new children who are properly suited for the new conditions. Robot children."
Inevitably, I ask whether he has any normal, flesh-and-blood children.
"No. In fact, I am biologically incapable of it. I contracted testicular cancer as I was finishing my PhD; it didn't affect me very much, it didn't really hurt, I noticed a growth, but I still had my thesis to write and my orals to do, and the whole thing seemed very unreal. There were two surgeries, one minor, one major - with my intestines out in a bag to get at the lymph nodes. I came through it in sparkling condition, aged around 30. But a side effect is that I'm basically infertile."
Does this mean that his love of robots is nothing more than a displaced desire for the biological children he can't have?
"Not at all. Long before the cancer, I was already obsessively committed to robots for whatever neurotic reason. That was where I wanted to spend my energy. I met my wife in the hospital when I was getting chemotherapy in 1980. She already had two children, so I inherited them as stepchildren."
Does his wife share any of his feelings about machines?
He laughs. "At the moment, my wife is a biblical scholar."
Moravec himself was raised Catholic, but he rebelled against it as a teenager and says he still has some anti-Catholic reflexes. As a result, he and his wife had some bitter theological debates in the past. "But these days there's no point in arguing," he says, "because we already know exactly what each other is going to say, and in any case she's more astute in human relations than I am, so she knows how to handle me. But I have changed my outlook slightly. I'm a little less hard-core in my atheism than I used to be. And my ideas about resurrection in some ways are not so different from those of early theologians, or from the Greek thought that fed into that."
Also, of course, the desire for human transcendence has been a fundamental feature of almost all religions. And Moravec's vision of a supremely powerful artificial intelligence that will love humanity enough to re-create it is basically a vision of a god - the only difference being that in his scheme of things, we create god version 1.0, after which it builds its own enhancements.
But how does all this fit in with Moravec's obvious personal love for machines?
"My father was an engineer in Czechoslovakia and had a business making and selling electrical goods during the war. When the Russians arrived in 1944, he became a refugee. He left the country on a tricycle with 50 kilos of tools and 50 kilos of food. He met my mother in Austria, which is where I was born. He had an electrical store, where he'd hand wind transformers to convert battery-operated radios so they'd run on house current. We relocated to Canada in 1953."
This marks the point where the genie finally gets out of the bottle and Earth's retirement community of pampered humans finds itself faced with a big problem. Out in space, the preprogrammed drive to compete and be efficient will result in the runaway evolution of machine capabilities.
Moravec feels that in a short period of time, all the local materials will be plundered and converted into machines, and all available solar energy will be used to power them.
The result will be a dense, interacting swarm of competing entities - although, he says, the competition will be relatively benign. Warfare among robots will be rare because "fighting wastes energy, and a third entity can eat the pieces."
He believes that the most useful skill will be intelligence. Robots will be motivated to make themselves as small as possible, conserving raw materials to build better brains. "As a result, you end up with the whole mess forming a cyberspace where entities try to outsmart each other by causing their way of thinking to be more pervasive. Here's an ecology where all the dead-matter activity has been squeezed out and almost everything that happens is meaningful. You have this sphere of cyberspace with a robot shell, expanding outward toward Earth."
What will it look like?
"It will look like a region of space glowing warmly, with hardly anything visible on a human scale. The competitive pressure toward miniaturization will result in activity on the subatomic level. They'll transform matter in some way; it will no longer be matter as we know it."
Since space-based machine intelligences will be free to develop at their own pace, they will quickly outstrip their cousins on Earth and eventually will be tempted to use the planet for their own purposes. "I don't think humanity will last long under these conditions," Moravec says. But, ever the optimist, he believes that "the takeover will be swift and painless."
Why? Because machine intelligence will be so far advanced, so incomprehensible to human beings, that we literally won't know what hit us. Moravec foresees a kind of happy ending, though, because the cyberspace entities should find human activity interesting from a historical perspective.
We will be remembered as their ancestors, the creators who enabled them to exist.
As Moravec puts it, "We are their past, and they will be interested in us for the same reason that today we are interested in the origins of our own life on Earth."
He seems very sincere as he says this, almost as if it's an article of faith for him - though of course it has some logical foundation. Machine intelligences of the far future will develop from our initial programming, just as a child grows from its parents' DNA. Consequently, even when robots are smarter than we are, they should retain many of our priorities and values.
But Moravec takes the scenario even one step further. Assuming the artificial intelligences now have truly overwhelming processing power, they should be able to reconstruct human society in every detail by tracing atomic events backward in time. "It will cost them very little to preserve us this way," he points out. "They will, in fact, be able to re-create a model of our entire civilization, with everything and everyone in it, down to the atomic level, simulating our atoms with machinery that's vastly subatomic. Also," he says with amusement, "they'll be able to use data compression to remove the redundant stuff that isn't important."
But by this logic, our current "reality" could be nothing more than a simulation produced by information entities.
"Of course." Moravec shrugs and waves his hand as if the idea is too obvious. "In fact, the robots will re-create us any number of times, whereas the original version of our world exists, at most, only once. Therefore, statistically speaking, it's much more likely we're living in a vast simulation than in the original version. To me, the whole concept of reality is rather absurd. But while you're inside the scenario, you can't help but play by the rules. So we might as well pretend this is real - even though the chance things are as they seem is essentially negligible."
And so, according to Hans Moravec, the human race is almost certainly extinct, while the world around us is just an advanced version of SimCity.
I've been sitting opposite Moravec in his office, typing on my laptop computer, following his exposition step by step. The vision he has described exists for him as a unified whole; it takes him only about an hour to describe it clearly and fluently from beginning to end. For him it seems entirely pleasurable: a destiny that grows out of his own work and affirms his own values.
Growing up in Montreal, learning English and adjusting to a strange new culture, Hans Moravec was a solitary child who found solace in building models and gadgets. "I remember the thrill I got when I put together something and made it work. I could admire it for hours. And these things also made other people proud of me. I guess I actually thought that they would get me a wife! I knew I didn't have any social skills, but maybe if I could build these machine things really, really well, it would make me more attractive to women." He laughs at his own childhood naïveté.
And yet, he didn't always want to be a scientist. First he wanted to be Superman. "But I could see that it wasn't practical. Then I noticed another character in the comics, Lex Luthor, who didn't have superpowers but was almost a match for Superman. So, I thought if I couldn't be Superman, maybe I could be Lex Luthor."
In person, Moravec seems diffident and gentle; he doesn't drive a car because, he says, he's uneasy with so much potentially dangerous mass in his control. He likes living in Pittsburgh because his home is a short walk from his office, and he seems to feel little need to venture outside this simple life.
Yet as a child he enjoyed fantasies about superheroes and supervillains, and as an adult he talks casually of totally rebuilding human society. He refers to his new book, for which he's currently seeking a publisher, as "a kind of speculative long-term business plan for humanity," and in it he speaks condescendingly of "Earth's small-minded biological natives." Can Moravec really claim that his work as a scientist is in no way manipulative?
"People such as myself," he says, "may have a little bit of influence, but we're like mosquitoes pushing at a rolling boulder. Progress is inflicted on people in the same way that natural evolution is inflicted on people. It really is evolution; it's the selection and growth of information, transmitted from one generation to the next."
But what about the rights of people who don't love the rolling boulder of progress?
"Well," he says, beginning to sound a little impatient with my objections, "they'll - they'll get used to it! In fact, they should enjoy it, since the amount of wealth will be astronomical; you'll be able to live anywhere and in any way you want."
In any case, he says, the progress he's talking about will be offered via the free market, not physically imposed on anyone. "All I'm suggesting is that we give people a choice. In the next decade, people will either buy their housecleaning robot or not buy it. And I think they'll want to buy it. Then they'll have the choice of upgrading to one that learns, and I think they'll want that, too. Then they'll have the choice of a robot that claims it's conscious, a really nice entity that talks like a person, seems to understand you, and has nothing but your best interests at heart - because that's how it's programmed. And then the fourth generation will take that personality and add intelligence. It will be a constant help to you; it will explain why something that you want to do isn't what you should do - because it loves you. I think people will like these machines and will quickly get used to them."
Well, yes - until the machines cut loose, develop hyperintelligence, and bring about our demise.
"But I don't consider it a demise," Moravec retorts, still insisting that his vision is wholly positive. "The robots will be a continuation of us, and they won't mean our extinction any more than a new generation of children spells the extinction of the previous generation of adults. In any case, in the long term, the robots are much more likely to resurrect us than our biological children are."
For people who find long-term resurrection a somewhat nebulous concept, there are also some practical reasons why we should be happy to change ourselves radically. On a long-term basis, Moravec points out, our planet may not be a hospitable place to live. Huge climatic shifts may occur (as they did during the ice ages). Our sun may become unstable. The world may be ravaged by incurable diseases. Our entire ecology could be destroyed by a large meteor or comet. "Sooner or later," he says, "something big will come along that we cannot deal with. But by changing ourselves in the most fundamental way, we will be able to survive such catastrophes."
This is an arguable point of view, but I can't help wondering which came first, Moravec's personal interest in becoming more than human, or his proof that it's really a very good idea. He readily admits that he has a personal obsession with robots, and his passion for transcendence is far more extreme than that of most scientists. What makes him so different from everyone else?
"Well, I was breast-fed as a baby," he answers with typically disconcerting candor. "I was also the first born of my family, and I was well loved by my mother - which must have helped me feel confident about life." He pauses, realizing that this explanation isn't adequate. "Maybe the idea of human transcendence makes me happy because my endorphin levels were misadjusted early on in life," he says with a laugh and a shrug, unable to come up with a better answer.
Personally, I suspect he likes the idea of radical change because he's an intensely intelligent man who is easily bored by the everyday world. He finds it impossible to believe that it makes sense to continue, as human beings, in our exact same form. "Do we really want more of what we have now?" he asks, sounding incredulous. "More millennia of the same old human soap opera? Surely we have played out most of the interesting scenarios already in terms of human relationships in a trivial framework. What I'm talking about transcends all that. There'll be far more interesting stories. And what is life but a set of stories?"
Ultimately, Moravec comes back again to the power and grandeur of a destiny that exceeds all limits. "This universe is so big," he says. "The possibilities must be infinitely greater than anything we can imagine for ourselves. Pushing things in the direction of expanded possibilities seems to be by far the most productive use of my time. And that, here, is my purpose."
By: Charles Platt
http://www.primitivism.com/superhumanism.htm