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1 #+TITLE:Transcript of Aaron Sloman - Artificial Intelligence - Psychology - Oxford Interview2 #+AUTHOR:Dylan Holmes3 #+EMAIL:4 #+STYLE: <link rel="stylesheet" type="text/css" href="../css/sloman.css" />7 #+begin_quote8 *Update* (13 Oct): Aaron Sloman has produced an improved version of9 this transcript, which includes follow-up thoughts and links to10 related works. It is available on his website here:11 [[http://www.cs.bham.ac.uk/research/projects/cogaff/movies/transcript-interview.html]].14 This draft will remain available here for historical purposes.15 #+end_quote17 #+BEGIN_QUOTE20 *Editor's note:* This is a working draft transcript which I made of21 [[http://www.youtube.com/watch?feature=player_detailpage&v=iuH8dC7Snno][this nice interview]] of Aaron Sloman. Having just finished one22 iteration of transcription, I still need to go in and clean up the23 formatting and fix the parts that I misheard, so you can expect the24 text to improve significantly in the near future.26 To the extent that this is my work, you have my permission to make27 copies of this transcript for your own purposes. Also, feel free to28 e-mail me with comments or corrections.30 (Addendum: This transcription is licensed by Aaron Sloman and Dylan Holmes, as31 indicated here:32 http://www.cs.bham.ac.uk/research/projects/cogaff/movies/transcript-interview.html#license)35 You can send mail to =transcript@aurellem.org=.37 Cheers,39 ---Dylan40 #+END_QUOTE45 * Introduction47 ** Aaron Sloman evolves into a philosopher of AI48 [0:09] My name is Aaron Sloman. My first degree many years ago in49 Capetown University was in Physics and Mathematics, and I intended to50 go and be a mathematician. I came to Oxford and encountered51 philosophers --- I had started reading philosophy and discussing52 philosophy before then, and then I found that there were philosophers53 who said things about mathematics that I thought were wrong, so54 gradually got more and more involved in [philosophy] discussions and55 switched to doing philosophy DPhil. Then I became a philosophy56 lecturer and about six years later, I was introduced to artificial57 intelligence when I was a lecturer at Sussex University in philosophy58 and I very soon became convinced that the best way to make progress in59 both areas of philosophy (including philosophy of mathematics which I60 felt i hadn't dealt with adequately in my DPhil) about the philosophy61 of mathematics, philosophy of mind, philsophy of language and all62 those things---the best way was to try to design and test working63 fragments of mind and maybe eventually put them all together but64 initially just working fragments that would do various things.66 [1:12] And I learned to program and ~ with various other people67 including ~Margaret Boden whom you've interviewed, developed---helped68 develop an undergraduate degree in AI and other things and also began69 to do research in AI and so on which I thought of as doing philosophy,70 primarily.72 [1:29] And then I later moved to the University of Birmingham and I73 was there --- I came in 1991 --- and I've been retired for a while but74 I'm not interested in golf or gardening so I just go on doing full75 time research and my department is happy to keep me on without paying76 me and provide space and resources and I come, meeting bright people77 at conferences and try to learn and make progress if I can.79 ** AI is hard, in part because there are tempting non-problems.81 One of the things I learnt and understood more and more over the many82 years --- forty years or so since I first encountered AI --- is how83 hard the problems are, and in part that's because it's very often84 tempting to /think/ the problem is something different from what it85 actually is, and then people design solutions to the non-problems, and86 I think of most of my work now as just helping to clarify what the87 problems are: what is it that we're trying to explain --- and maybe88 this is leading into what you wanted to talk about:90 I now think that one of the ways of getting a deep understanding of91 that is to find out what were the problems that biological evolution92 solved, because we are a product of /many/ solutions to /many/93 problems, and if we just try to go in and work out what the whole94 system is doing, we may get it all wrong, or badly wrong.97 * What problems of intelligence did evolution solve?99 ** Intelligence consists of solutions to many evolutionary problems; no single development (e.g. communication) was key to human-level intelligence.101 [2:57] Well, first I would challenge that we are the dominant102 species. I know it looks like that but actually if you count biomass,103 if you count number of species, if you count number of individuals,104 the dominant species are microbes --- maybe not one of them but anyway105 they're the ones who dominate in that sense, and furthermore we are106 mostly --- we are largely composed of microbes, without which we107 wouldn't survive.110 # ** Many nonlinguistic competences require sophisticated internal representations111 [3:27] But there are things that make humans (you could say) best at112 those things, or worst at those things, but it's a combination. And I113 think it was a collection of developments of which there isn't any114 single one. [] there might be, some people say, human language which115 changed everything. By our human language, they mean human116 communication in words, but I think that was a later development from117 what must have started as the use of /internal/ forms of118 representation --- which are there in nest-building birds, in119 pre-verbal children, in hunting mammals --- because you can't take in120 information about a complex structured environment in which things can121 change and you may have to be able to work out what's possible and122 what isn't possible, without having some way of representing the123 components of the environment, their relationships, the kinds of124 things they can and can't do, the kinds of things you might or might125 not be able to do --- and /that/ kind of capability needs internal126 languages, and I and colleagues [at Birmingham] have been referring to127 them as generalized languages because some people object to128 referring...to using language to refer to something that isn't used129 for communication. But from that viewpoint, not only humans but many130 other animals developed abilities to do things to their environment to131 make them more friendly to themselves, which depended on being able to132 represent possible futures, possible actions, and work out what's the133 best thing to do.135 [5:13] And nest-building in corvids for instance---crows, magpies,136 [hawks], and so on --- are way beyond what current robots can do, and137 in fact I think most humans would be challenged if they had to go and138 find a collection of twigs, one at a time, maybe bring them with just139 one hand --- or with your mouth --- and assemble them into a140 structure that, you know, is shaped like a nest, and is fairly rigid,141 and you could trust your eggs in them when wind blows. But they're142 doing it, and so ... they're not our evolutionary ancestors, but143 they're an indication --- and that example is an indication --- of144 what must have evolved in order to provide control over the145 environment in /that/ species.147 ** Speculation about how communication might have evolved from internal lanagues.148 [5:56] And I think hunting mammals, fruit-picking mammals, mammals149 that can rearrange parts of the environment, provide shelters, needed150 to have .... also needed to have ways of representing possible151 futures, not just what's there in the environment. I think at a later152 stage, that developed into a form of communication, or rather the153 /internal/ forms of representation became usable as a basis for154 providing [context] to be communicated. And that happened, I think,155 initially through performing actions that expressed intentions, and156 probably led to situtations where an action (for instance, moving some157 large object) was performed more easily, or more successfully, or more158 accurately if it was done collaboratively. So someone who had worked159 out what to do might start doing it, and then a conspecific might be160 able to work out what the intention is, because that person has the161 /same/ forms of representation and can build theories about what's162 going on, and might then be able to help.164 [7:11] You can imagine that if that started happening more (a lot of165 collaboration based on inferred intentions and plans) then sometimes166 the inferences might be obscure and difficult, so the /actions/ might167 be enhanced to provide signals as to what the intention is, and what168 the best way is to help, and so on.170 [7:35] So, this is all handwaving and wild speculation, but I think171 it's consistent with a large collection of facts which one can look at172 --- and find if one looks for them, but one won't know if [some]one173 doesn't look for them --- about the way children, for instance, who174 can't yet talk, communicate, and the things they'll do, like going to175 the mother and turning the face to point in the direction where the176 child wants it to look and so on; that's an extreme version of action177 indicating intention.179 [8:03] Anyway. That's a very long roundabout answer to one conjecture180 that the use of communicative language is what gave humans their181 unique power to create and destroy and whatever, and I'm saying that182 if by that you mean /communicative/ language, then I'm saying there183 was something before that which was /non/-communicative language, and I184 suspect that noncommunicative language continues to play a deep role185 in /all/ human perception ---in mathematical and scientific reasoning, in186 problem solving --- and we don't understand very much about it.188 [8:48]189 I'm sure there's a lot more to be said about the development of190 different kinds of senses, the development of brain structures and191 mechanisms is above all that, but perhaps I've droned on long enough192 on that question.195 * How do language and internal states relate to AI?197 [9:09] Well, I think most of the human and animal capabilities that198 I've been referring to are not yet to be found in current robots or199 [computing] systems, and I think there are two reasons for that: one200 is that it's intrinsically very difficult; I think that in particular201 it may turn out that the forms of information processing that one can202 implement on digital computers as we currently know them may not be as203 well suited to performing some of these tasks as other kinds of204 computing about which we don't know so much --- for example, I think205 there may be important special features about /chemical/ computers206 which we might [talk about in a little bit? find out about].208 ** In AI, false assumptions can lead investigators astray.209 [9:57] So, one of the problems then is that the tasks are hard ... but210 there's a deeper problem as to why AI hasn't made a great deal of211 progress on these problems that I'm talking about, and that is that212 most AI researchers assume things---and this is not just AI213 researchers, but [also] philsophers, and psychologists, and people214 studying animal behavior---make assumptions about what it is that215 animals or humans do, for instance make assumptions about what vision216 is for, or assumptions about what motivation is and how motivation217 works, or assumptions about how learning works, and then they try ---218 the AI people try --- to model [or] build systems that perform those219 assumed functions. So if you get the /functions/ wrong, then even if220 you implement some of the functions that you're trying to implement,221 they won't necessarily perform the tasks that the initial objective222 was to imitate, for instance the tasks that humans, and nest-building223 birds, and monkeys and so on can perform.225 ** Example: Vision is not just about finding surfaces, but about finding affordances.226 [11:09] I'll give you a simple example --- well, maybe not so simple,227 but --- It's often assumed that the function of vision in humans (and228 in other animals with good eyesight and so on) is to take in optical229 information that hits the retina, and form into the (maybe changing230 --- or, really, in our case definitely changing) patterns of231 illumination where there are sensory receptors that detect those232 patterns, and then somehow from that information (plus maybe other233 information gained from head movement or from comparisons between two234 eyes) to work out what there was in the environment that produced235 those patterns, and that is often taken to mean \ldquo{}where were the236 surfaces off which the light bounced before it came to me\rdquo{}. So237 you essentially think of the task of the visual system as being to238 reverse the image formation process: so the 3D structure's there, the239 lens causes the image to form in the retina, and then the brain goes240 back to a model of that 3D structure there. That's a very plausible241 theory about vision, and it may be that that's a /subset/ of what242 human vision does, but I think James Gibson pointed out that that kind243 of thing is not necessarily going to be very useful for an organism,244 and it's very unlikely that that's the main function of perception in245 general, namely to produce some physical description of what's out246 there.248 [12:37] What does an animal /need/? It needs to know what it can do,249 what it can't do, what the consequences of its actions will be250 .... so, he introduced the word /affordance/, so from his point of251 view, the function of vision, perception, are to inform the organism252 of what the /affordances/ are for action, where that would mean what253 the animal, /given/ its morphology (what it can do with its mouth, its254 limbs, and so on, and the ways it can move) what it can do, what its255 needs are, what the obstacles are, and how the environment supports or256 obstructs those possible actions.258 [13:15] And that's a very different collection of information259 structures that you need from, say, \ldquo{}where are all the260 surfaces?\rdquo{}: if you've got all the surfaces, /deriving/ the261 affordances would still be a major task. So, if you think of the262 perceptual system as primarily (for biological organisms) being263 devices that provide information about affordances and so on, then the264 tasks look very different. And most of the people working, doing265 research on computer vision in robots, I think haven't taken all that266 on board, so they're trying to get machines to do things which, even267 if they were successful, would not make the robots very intelligent268 (and in fact, even the ones they're trying to do are not really easy269 to do, and they don't succeed very well--- although, there's progress;270 I shouldn't disparage it too much.)272 ** Online and offline intelligence274 [14:10] It gets more complex as animals get more sophisticated. So, I275 like to make a distinction between online intelligence and offline276 intelligence. So, for example, if I want to pick something up --- like277 this leaf <he plucks a leaf from the table> --- I was able to select278 it from all the others in there, and while moving my hand towards it,279 I was able to guide its trajectory, making sure it was going roughly280 in the right direction --- as opposed to going out there, which281 wouldn't have been able to pick it up --- and these two fingers ended282 up with a portion of the leaf between them, so that I was able to tell283 when I'm ready to do that <he clamps the leaf between two fingers>284 and at that point, I clamped my fingers and then I could pick up the285 leaf.287 [14:54] Whereas, --- and that's an example of online intelligence:288 during the performance of an action (both from the stage where it's289 initiated, and during the intermediate stages, and where it's290 completed) I'm taking in information relevant to controlling all those291 stages, and that relevant information keeps changing. That means I292 need stores of transient information which gets discarded almost293 immediately and replaced or something. That's online intelligence. And294 there are many forms; that's just one example, and Gibson discussed295 quite a lot of examples which I won't try to replicate now.297 [15:30] But in offline intelligence, you're not necessarily actually298 /performing/ the actions when you're using your intelligence; you're299 thinking about /possible/ actions. So, for instance, I could think300 about how fast or by what route I would get back to the lecture room301 if I wanted to [get to the next talk] or something. And I know where302 the door is, roughly speaking, and I know roughly which route I would303 take, when I go out, I should go to the left or to the right, because304 I've stored information about where the spaces are, where the305 buildings are, where the door was that we came out --- but in using306 that information to think about that route, I'm not actually307 performing the action. I'm not even /simulating/ it in detail: the308 precise details of direction and speed and when to clamp my fingers,309 or when to contract my leg muscles when walking, are all irrelevant to310 thinking about a good route, or thinking about the potential things311 that might happen on the way. Or what would be a good place to meet312 someone who I think [for an acquaintance in particular] --- [barber]313 or something --- I don't necessarily have to work out exactly /where/314 the person's going to stand, or from what angle I would recognize315 them, and so on.317 [16:46] So, offline intelligence --- which I think became not just a318 human competence; I think there are other animals that have aspects of319 it: Squirrels are very impressive as you watch them. Gray squirrels at320 any rate, as you watch them defeating squirrel-proof birdfeeders, seem321 to have a lot of that [offline intelligence], as well as the online322 intelligence when they eventually perform the action they've worked323 out [] that will get them to the nuts.325 [17:16] And I think that what happened during our evolution is that326 mechanisms for acquiring and processing and storing and manipulating327 information that is more and more remote from the performance of328 actions developed. An example is taking in information about where329 locations are that you might need to go to infrequently: There's a330 store of a particular type of material that's good for building on331 roofs of houses or something out around there in some332 direction. There's a good place to get water somewhere in another333 direction. There are people that you'd like to go and visit in334 another place, and so on.336 [17:59] So taking in information about an extended environment and337 building it into a structure that you can make use of for different338 purposes is another example of offline intelligence. And when we do339 that, we sometimes use only our brains, but in modern times, we also340 learned how to make maps on paper and walls and so on. And it's not341 clear whether the stuff inside our heads has the same structures as342 the maps we make on paper: the maps on paper have a different343 function; they may be used to communicate with others, or meant for344 /looking/ at, whereas the stuff in your head you don't /look/ at; you345 use it in some other way.347 [18:46] So, what I'm getting at is that there's a great deal of human348 intelligence (and animal intelligence) which is involved in what's349 possible in the future, what exists in distant places, what might have350 happened in the past (sometimes you need to know why something is as351 it is, because that might be relevant to what you should or shouldn't352 do in the future, and so on), and I think there was something about353 human evolution that extended that offline intelligence way beyond354 that of animals. And I don't think it was /just/ human language, (but355 human language had something to do with it) but I think there was356 something else that came earlier than language which involves the357 ability to use your offline intelligence to discover something that358 has a rich mathematical structure.360 ** Example: Even toddlers use sophisticated geometric knowledge361 #+<<example-gap>>362 [19:44] I'll give you a simple example: if you look through a gap, you363 can see something that's on the other side of the gap. Now, you364 /might/ see what you want to see, or you might see only part of it. If365 you want to see more of it, which way would you move? Well, you could366 either move /sideways/, and see through the gap---and see it roughly367 the same amount but a different part of it [if it's a ????], or you368 could move /towards/ the gap and then your view will widen as you369 approach the gap. Now, there's a bit of mathematics in there, insofar370 as you are implicitly assuming that information travels in straight371 lines, and as you go closer to a gap, the straight lines that you can372 draw from where you are through the gap, widen as you approach that373 gap. Now, there's a kind of theorem of Euclidean geometry in there374 which I'm not going to try to state very precisely (and as far as I375 know, wasn't stated explicitly in Euclidean geometry) but it's376 something every toddler--- human toddler---learns. (Maybe other377 animals also know it, I don't know.) But there are many more things,378 actions to perform, to get you more information about things, actions379 to perform to conceal information from other people, actions that will380 enable you to operate, to act on a rigid object in one place in order381 to produce an effect on another place. So, there's a lot of stuff that382 involves lines and rotations and angles and speeds and so on that I383 think humans (maybe, to a lesser extent, other animals) develop the384 ability to think about in a generic way. That means that you could385 take out the generalizations from the particular contexts and then386 re-use them in a new contexts in ways that I think are not yet387 represented at all in AI and in theories of human learning in any []388 way --- although some people are trying to study learning of mathematics.390 * Animal intelligence392 ** The priority is /cataloguing/ what competences have evolved, not ranking them.393 [22:03] I wasn't going to challenge the claim that humans can do more394 sophisticated forms of [tracking], just to mention that there are some395 things that other animals can do which are in some ways comparable,396 and some ways superior to [things] that humans can do. In particular,397 there are species of birds and also, I think, some rodents ---398 squirrels, or something --- I don't know enough about the variety ---399 that can hide nuts and remember where they've hidden them, and go back400 to them. And there have been tests which show that some birds are able401 to hide tens --- you know, [eighteen] or something nuts --- and to402 remember which ones have been taken, which ones haven't, and so403 on. And I suspect most humans can't do that. I wouldn't want to say404 categorically that maybe we couldn't, because humans are very405 [varied], and also [a few] people can develop particular competences406 through training. But it's certainly not something I can do.409 ** AI can be used to test philosophical theories410 [23:01] But I also would like to say that I am not myself particularly411 interested in trying to align animal intelligences according to any412 kind of scale of superiority; I'm just trying to understand what it413 was that biological evolution produced, and how it works, and I'm414 interested in AI /mainly/ because I think that when one comes up with415 theories about how these things work, one needs to have some way of416 testing the theory. And AI provides ways of implementing and testing417 theories that were not previously available: Immanuel Kant was trying418 to come up with theories about how minds work, but he didn't have any419 kind of a mechanism that he could build to test his theory about the420 nature of mathematical knowledge, for instance, or how concepts were421 developed from babyhood onward. Whereas now, if we do develop a422 theory, we have a criterion of adequacy, namely it should be precise423 enough and rich enough and detailed to enable a model to be424 built. And then we can see if it works.426 [24:07] If it works, it doesn't mean we've proved that the theory is427 correct; it just shows it's a candidate. And if it doesn't work, then428 it's not a candidate as it stands; it would need to be modified in429 some way.431 * Is abstract general intelligence feasible?433 ** It's misleading to compare the brain and its neurons to a computer made of transistors434 [24:27] I think there's a lot of optimism based on false clues:435 the...for example, one of the false clues is to count the number of436 neurons in the brain, and then talk about the number of transistors437 you can fit into a computer or something, and then compare them. It438 might turn out that the study of the way synapses work (which leads439 some people to say that a typical synapse [] in the human brain has440 computational power comparable to the Internet a few years ago,441 because of the number of different molecules that are doing things,442 the variety of types of things that are being done in those molecular443 interactions, and the speed at which they happen, if you somehow count444 up the number of operations per second or something, then you get445 these comparable figures).447 ** For example, brains may rely heavily on chemical information processing448 Now even if the details aren't right, there may just be a lot of449 information processing that...going on in brains at the /molecular/450 level, not the neural level. Then, if that's the case, the processing451 units will be orders of magnitude larger in number than the number of452 neurons. And it's certainly the case that all the original biological453 forms of information processing were chemical; there weren't brains454 around, and still aren't in most microbes. And even when humans grow455 their brains, the process of starting from a fertilized egg and456 producing this rich and complex structure is, for much of the time,457 under the control of chemical computations, chemical information458 processing---of course combined with physical sorts of materials and459 energy and so on as well.461 [26:25] So it would seem very strange if all that capability was462 something thrown away when you've got a brain and all the information463 processing, the [challenges that were handled in making a brain],464 ... This is handwaving on my part; I'm just saying that we /might/465 learn that what brains do is not what we think they do, and that466 problems of replicating them are not what we think they are, solely in467 terms of numerical estimate of time scales, the number of components,468 and so on.470 ** Brain algorithms may simply be optimized for certain kinds of information processing other than bit manipulations471 [26:56] But apart from that, the other basis of skepticism concerns472 how well we understand what the problems are. I think there are many473 people who try to formalize the problems of designing an intelligent474 system in terms of streams of information thought of as bit streams or475 collections of bit streams, and they think of as the problems of476 intelligence as being the construction or detection of patterns in477 those, and perhaps not just detection of patterns, but detection of478 patterns that are useable for sending /out/ streams to control motors479 and so on in order to []. And that way of conceptualizing the problem480 may lead on the one hand to oversimplification, so that the things481 that /would/ be achieved, if those goals were achieved, maybe much482 simpler, in some ways inadequate. Or the replication of human483 intelligence, or the matching of human intelligence---or for that484 matter, squirrel intelligence---but in another way, it may also make485 the problem harder: it may be that some of the kinds of things that486 biological evolution has achieved can't be done that way. And one of487 the ways that might turn out to be the case is not because it's not488 impossible in principle to do some of the information processing on489 artificial computers-based-on-transistors and other bit-manipulating490 []---but it may just be that the computational complexity of solving491 problems, processes, or finding solutions to complex problems, are492 much greater and therefore you might need a much larger universe than493 we have available in order to do things.495 ** Example: find the shortest path by dangling strings496 [28:55] Then if the underlying mechanisms were different, the497 information processing mechanisms, they might be better tailored to498 particular sorts of computation. There's a [] example, which is499 finding the shortest route if you've got a collection of roads, and500 they may be curved roads, and lots of tangled routes from A to B to C,501 and so on. And if you start at A and you want to get to Z --- a place502 somewhere on that map --- the process of finding the shortest route503 will involve searching through all these different possibilities and504 rejecting some that are longer than others and so on. But if you make505 a model of that map out of string, where these strings are all laid506 out on the maps and so have the lengths of the routes. Then if you507 hold the two knots in the string -- it's a network of string --- which508 correspond to the start point and end point, then /pull/, then the509 bits of string that you're left with in a straight line will give you510 the shortest route, and that process of pulling just gets you the511 solution very rapidly in a parallel computation, where all the others512 just hang by the wayside, so to speak.514 ** In sum, we know surprisingly little about the kinds of problems that evolution solved, and the manner in which they were solved.515 [30:15] Now, I'm not saying brains can build networks of string and516 pull them or anything like that; that's just an illustration of how if517 you have the right representation, correctly implemented---or suitably518 implemented---for a problem, then you can avoid very combinatorially519 complex searches, which will maybe grow exponentially with the number520 of components in your map, whereas with this thing, the time it takes521 won't depend on how many strings you've [got on the map]; you just522 pull, and it will depend only on the shortest route that exists in523 there. Even if that shortest route wasn't obvious on the original map.526 [30:59] So that's a rather long-winded way of formulating the527 conjecture which---of supporting, a roundabout way of supporting the528 conjecture that there may be something about the way molecules perform529 computations where they have the combination of continuous change as530 things move through space and come together and move apart, and531 whatever --- and also snap into states that then persist, so [as you532 learn from] quantum mechanics, you can have stable molecular533 structures which are quite hard to separate, and then in catalytic534 processes you can separate them, or extreme temperatures, or strong535 forces, but they may nevertheless be able to move very rapidly in some536 conditions in order to perform computations.538 [31:49] Now there may be things about that kind of structure that539 enable searching for solutions to /certain/ classes of problems to be540 done much more efficiently (by brain) than anything we could do with541 computers. It's just an open question.543 [32:04] So it /might/ turn out that we need new kinds of technology544 that aren't on the horizon in order to replicate the functions that545 animal brains perform ---or, it might not. I just don't know. I'm not546 claiming that there's strong evidence for that; I'm just saying that547 it might turn out that way, partly because I think we know less than548 many people think we know about what biological evolution achieved.550 [32:28] There are some other possibilities: we may just find out that551 there are shortcuts no one ever thought of, and it will all happen552 much more quickly---I have an open mind; I'd be surprised, but it553 could turn up. There /is/ something that worries me much more than the554 singularity that most people talk about, which is machines achieving555 human-level intelligence and perhaps taking over [the] planet or556 something. There's what I call the /singularity of cognitive557 catch-up/ ...559 * A singularity of cognitive catch-up561 ** What if it will take a lifetime to learn enough to make something new?562 ... SCC, singularity of cognitive catch-up, which I think we're close563 to, or maybe have already reached---I'll explain what I mean by564 that. One of the products of biological evolution---and this is one of565 the answers to your earlier questions which I didn't get on to---is566 that humans have not only the ability to make discoveries that none of567 their ancestors have ever made, but to shorten the time required for568 similar achievements to be reached by their offspring and their569 descendants. So once we, for instance, worked out ways of complex570 computations, or ways of building houses, or ways of finding our way571 around, we don't need...our children don't need to work it out for572 themselves by the same lengthy trial and error procedure; we can help573 them get there much faster.575 Okay, well, what I've been referring to as the singularity of576 cognitive catch-up depends on the fact that---fairly obvious, and it's577 often been commented on---that in case of humans, it's not necessary578 for each generation to learn what previous generations learned /in the579 same way/. And we can speed up learning once something has been580 learned, [it is able to] be learned by new people. And that has meant581 that the social processes that support that kind of education of the582 young can enormously accelerate what would have taken...perhaps583 thousands [or] millions of years for evolution to produce, can happen in584 a much shorter time.587 [34:54] But here's the catch: in order for a new advance to happen ---588 so for something new to be discovered that wasn't there before, like589 Newtonian mechanics, or the theory of relativity, or Beethoven's music590 or [style] or whatever --- the individuals have to have traversed a591 significant amount of what their ancestors have learned, even if they592 do it much faster than their ancestors, to get to the point where they593 can see the gaps, the possibilities for going further than their594 ancestors, or their parents or whatever, have done.596 [35:27] Now in the case of knowledge of science, mathematics,597 philosophy, engineering and so on, there's been a lot of accumulated598 knowledge. And humans are living a /bit/ longer than they used to, but599 they're still living for [whatever it is], a hundred years, or for600 most people, less than that. So you can imagine that there might come601 a time when in a normal human lifespan, it's not possible for anyone602 to learn enough to understand the scope and limits of what's already603 been achieved in order to see the potential for going beyond it and to604 build on what's already been done to make that...those future steps.606 [36:10] So if we reach that stage, we will have reached the607 singularity of cognitive catch-up because the process of education608 that enables individuals to learn faster than their ancestors did is609 the catching-up process, and it may just be that we at some point610 reach a point where catching up can only happen within a lifetime of611 an individual, and after that they're dead and they can't go612 beyond. And I have some evidence that there's a lot of that around613 because I see a lot of people coming up with what /they/ think of as614 new ideas which they've struggled to come up with, but actually they615 just haven't taken in some of what was...some of what was done [] by616 other people, in other places before them. And I think that despite617 the availability of search engines which make it /easier/ for people618 to get the information---for instance, when I was a student, if I619 wanted to find out what other people had done in the field, it was a620 laborious process---going to the library, getting books, and621 ---whereas now, I can often do things in seconds that would have taken622 hours. So that means that if seconds [are needed] for that kind of623 work, my lifespan has been extended by a factor of ten or624 something. So maybe that /delays/ the singularity, but it may not625 delay it enough. But that's an open question; I don't know. And it may626 just be that in some areas, this is more of a problem than others. For627 instance, it may be that in some kinds of engineering, we're handing628 over more and more of the work to machines anyways and they can go on629 doing it. So for instance, most of the production of computers now is630 done by a computer-controlled machine---although some of the design631 work is done by humans--- a lot of /detail/ of the design is done by632 computers, and they produce the next generation, which then produces633 the next generation, and so on.635 [37:57] I don't know if humans can go on having major advances, so636 it'll be kind of sad if we can't.638 * Spatial reasoning: a difficult problem640 [38:15] Okay, well, there are different problems [ ] mathematics, and641 they have to do with properties. So for instance a lot of mathematics642 that can be expressed in terms of logical structures or algebraic643 structures and those are pretty well suited for manipulation and...on644 computers, and if a problem can be specified using the645 logical/algebraic notation, and the solution method requires creating646 something in that sort of notation, then computers are pretty good,647 and there are lots of mathematical tools around---there are theorem648 provers and theorem checkers, and all kinds of things, which couldn't649 have existed fifty, sixty years ago, and they will continue getting650 better.653 But there was something that I was [[example-gap][alluding to earlier]] when I gave the654 example of how you can reason about what you will see by changing your655 position in relation to a door, where what you are doing is using your656 grasp of spatial structures and how as one spatial relationship657 changes namely you come closer to the door or move sideways and658 parallel to the wall or whatever, other spatial relationships change659 in parallel, so the lines from your eyes through to other parts of660 the...parts of the room on the other side of the doorway change,661 spread out more as you go towards the doorway, and as you move662 sideways, they don't spread out differently, but focus on different663 parts of the internal ... that they access different parts of the664 ... of the room.666 Now, those are examples of ways of thinking about relationships and667 changing relationships which are not the same as thinking about what668 happens if I replace this symbol with that symbol, or if I substitute669 this expression in that expression in a logical formula. And at the670 moment, I do not believe that there is anything in AI amongst the671 mathematical reasoning community, the theorem-proving community, that672 can model the processes that go on when a young child starts learning673 to do Euclidean geometry and is taught things about---for instance, I674 can give you a proof that the angles of any triangle add up to a675 straight line, 180 degrees.677 ** Example: Spatial proof that the angles of any triangle add up to a half-circle678 There are standard proofs which involves starting with one triangle,679 then adding a line parallel to the base one of my former students,680 Mary Pardoe, came up with which I will demonstrate with this <he holds681 up a pen> --- can you see it? If I have a triangle here that's got682 three sides, if I put this thing on it, on one side --- let's say the683 bottom---I can rotate it until it lies along the second...another684 side, and then maybe move it up to the other end ~. Then I can rotate685 it again, until it lies on the third side, and move it back to the686 other end. And then I'll rotate it again and it'll eventually end up687 on the original side, but it will have changed the direction it's688 pointing in --- and it won't have crossed over itself so it will have689 gone through a half-circle, and that says that the three angles of a690 triangle add up to the rotations of half a circle, which is a691 beautiful kind of proof and almost anyone can understand it. Some692 mathematicians don't like it, because they say it hides some of the693 assumptions, but nevertheless, as far as I'm concerned, it's an694 example of a human ability to do reasoning which, once you've695 understood it, you can see will apply to any triangle --- it's got to696 be a planar triangle --- not a triangle on a globe, because then the697 angles can add up to more than ... you can have three /right/ angles698 if you have an equator...a line on the equator, and a line going up to699 to the north pole of the earth, and then you have a right angle and700 then another line going down to the equator, and you have a right701 angle, right angle, right angle, and they add up to more than a702 straight line. But that's because the triangle isn't in the plane,703 it's on a curved surface. In fact, that's one of the704 differences...definitional differences you can take between planar and705 curved surfaces: how much the angles of a triangle add up to. But our706 ability to /visualize/ and notice the generality in that process, and707 see that you're going to be able to do the same thing using triangles708 that stretch in all sorts of ways, or if it's a million times as709 large, or if it's made...you know, written on, on...if it's drawn in710 different colors or whatever --- none of that's going to make any711 difference to the essence of that process. And that ability to see712 the commonality in a spatial structure which enables you to draw some713 conclusions with complete certainty---subject to the possibility that714 sometimes you make mistakes, but when you make mistakes, you can715 discover them, as has happened in the history of geometrical theorem716 proving. Imre Lakatos had a wonderful book called [[http://en.wikipedia.org/wiki/Proofs_and_Refutations][/Proofs and717 Refutations/]] --- which I won't try to summarize --- but he has718 examples: mistakes were made; that was because people didn't always719 realize there were subtle subcases which had slightly different720 properties, and they didn't take account of that. But once they're721 noticed, you rectify that.723 ** Geometric results are fundamentally different than experimental results in chemistry or physics.724 [43:28] But it's not the same as doing experiments in chemistry and725 physics, where you can't be sure it'll be the same on [] or at a high726 temperature, or in a very strong magnetic field --- with geometric727 reasoning, in some sense you've got the full information in front of728 you; even if you don't always notice an important part of it. So, that729 kind of reasoning (as far as I know) is not implemented anywhere in a730 computer. And most people who do research on trying to model731 mathematical reasoning, don't pay any attention to that, because of732 ... they just don't think about it. They start from somewhere else,733 maybe because of how they were educated. I was taught Euclidean734 geometry at school. Were you?736 (Adam ford: Yeah)738 Many people are not now. Instead they're taught set theory, and739 logic, and arithmetic, and [algebra], and so on. And so they don't use740 that bit of their brains, without which we wouldn't have built any of741 the cathedrals, and all sorts of things we now depend on.743 * Is near-term artificial general intelligence likely?745 ** Two interpretations: a single mechanism for all problems, or many mechanisms unified in one program.747 [44:35] Well, this relates to what's meant by general. And when I748 first encountered the AGI community, I thought that what they all749 meant by general intelligence was /uniform/ intelligence ---750 intelligence based on some common simple (maybe not so simple, but)751 single powerful mechanism or principle of inference. And there are752 some people in the community who are trying to produce things like753 that, often in connection with algorithmic information theory and754 computability of information, and so on. But there's another sense of755 general which means that the system of general intelligence can do756 lots of different things, like perceive things, understand language,757 move around, make things, and so on --- perhaps even enjoy a joke;758 that's something that's not nearly on the horizon, as far as I759 know. Enjoying a joke isn't the same as being able to make laughing760 noises.762 Given, then, that there are these two notions of general763 intelligence---there's one that looks for one uniform, possibly764 simple, mechanism or collection of ideas and notations and algorithms,765 that will deal with any problem that's solvable --- and the other766 that's general in the sense that it can do lots of different things767 that are combined into an integrated architecture (which raises lots768 of questions about how you combine these things and make them work769 together) and we humans, certainly, are of the second kind: we do all770 sorts of different things, and other animals also seem to be of the771 second kind, perhaps not as general as humans. Now, it may turn out772 that in some near future time, who knows---decades, a few773 decades---you'll be able to get machines that are capable of solving774 in a time that will depend on the nature of the problem, but any775 problem that is solvable, and they will be able to do it in some sort776 of tractable time --- of course, there are some problems that are777 solvable that would require a larger universe and a longer history778 than the history of the universe, but apart from that constraint,779 these machines will be able to do anything []. But to be able to do780 some of the kinds of things that humans can do, like the kinds of781 geometrical reasoning where you look at the shape and you abstract782 away from the precise angles and sizes and shapes and so on, and783 realize there's something general here, as must have happened when our784 ancestors first made the discoveries that eventually put together in785 Euclidean geometry.787 It may be that that requires mechanisms of a kind that we don't know788 anything about at the moment. Maybe brains are using molecules and789 rearranging molecules in some way that supports that kind of790 reasoning. I'm not saying they are --- I don't know, I just don't see791 any simple...any obvious way to map that kind of reasoning capability792 onto what we currently do on computers. There is---and I just793 mentioned this briefly beforehand---there is a kind of thing that's794 sometimes thought of as a major step in that direction, namely you can795 build a machine (or a software system) that can represent some796 geometrical structure, and then be told about some change that's going797 to happen to it, and it can predict in great detail what'll798 happen. And this happens for instance in game engines, where you say799 we have all these blocks on the table and I'll drop one other block,800 and then [the thing] uses Newton's laws and properties of rigidity of801 the parts and the elasticity and also stuff about geometries and space802 and so on, to give you a very accurate representation of what'll803 happen when this brick lands on this pile of things, [it'll bounce and804 go off, and so on]. And you just, with more memory and more CPU power,805 you can increase the accuracy--- but that's totally different than806 looking at /one/ example, and working out what will happen in a whole807 /range/ of cases at a higher level of abstraction, whereas the game808 engine does it in great detail for /just/ this case, with /just/ those809 precise things, and it won't even know what the generalizations are810 that it's using that would apply to others []. So, in that sense, [we]811 may get AGI --- artificial general intelligence --- pretty soon, but812 it'll be limited in what it can do. And the other kind of general813 intelligence which combines all sorts of different things, including814 human spatial geometrical reasoning, and maybe other things, like the815 ability to find things funny, and to appreciate artistic features and816 other things may need forms of pattern-mechanism, and I have an open817 mind about that.819 * Abstract General Intelligence impacts821 [49:53] Well, as far as the first type's concerned, it could be useful822 for all kinds of applications --- there are people who worry about823 where there's a system that has that type of intelligence, might in824 some sense take over control of the planet. Well, humans often do825 stupid things, and they might do something stupid that would lead to826 disaster, but I think it's more likely that there would be other827 things [] lead to disaster--- population problems, using up all the828 resources, destroying ecosystems, and whatever. But certainly it would829 go on being useful to have these calculating devices. Now, as for the830 second kind of them, I don't know---if we succeeded at putting831 together all the parts that we find in humans, we might just make an832 artificial human, and then we might have some of them as your friends,833 and some of them we might not like, and some of them might become834 teachers or whatever, composers --- but that raises a question: could835 they, in some sense, be superior to us, in their learning836 capabilities, their understanding of human nature, or maybe their837 wickedness or whatever --- these are all issues in which I expect the838 best science fiction writers would give better answers than anything I839 could do, but I did once fantasize when I [back] in 1978, that perhaps840 if we achieved that kind of thing, that they would be wise, and gentle841 and kind, and realize that humans are an inferior species that, you842 know, have some good features, so they'd keep us in some kind of843 secluded...restrictive kind of environment, keep us away from844 dangerous weapons, and so on. And find ways of cohabitating with845 us. But that's just fantasy.847 Adam Ford: Awesome. Yeah, there's an interesting story /With Folded848 Hands/ where [the computers] want to take care of us and want to849 reduce suffering and end up lobotomizing everybody [but] keeping them850 alive so as to reduce the suffering.852 Aaron Sloman: Not all that different from /Brave New World/, where it853 was done with drugs and so on, but different humans are given854 different roles in that system, yeah.856 There's also /The Time Machine/, H.G. Wells, where the ... in the857 distant future, humans have split in two: the Eloi, I think they were858 called, they lived underground, they were the [] ones, and then---no,859 the Morlocks lived underground; Eloi lived on the planet; they were860 pleasant and pretty but not very bright, and so on, and they were fed861 on by ...863 Adam Ford: [] in the future.865 Aaron Sloman: As I was saying, if you ask science fiction writers,866 you'll probably come up with a wide variety of interesting answers.868 Adam Ford: I certainly have; I've spoken to [] of Birmingham, and869 Sean Williams, ... who else?871 Aaron Sloman: Did you ever read a story by E.M. Forrester called /The872 Machine Stops/ --- very short story, it's [[http://archive.ncsa.illinois.edu/prajlich/forster.html][on the Internet somewhere]]873 --- it's about a time when people sitting ... and this was written in874 about [1914 ] so it's about...over a hundred years ago ... people are875 in their rooms, they sit in front of screens, and they type things,876 and they communicate with one another that way, and they don't meet;877 they have debates, and they give lectures to their audiences that way,878 and then there's a woman whose son says \ldquo{}I'd like to see879 you\rdquo{} and she says \ldquo{}What's the point? You've got me at880 this point \rdquo{} but he wants to come and talk to her --- I won't881 tell you how it ends, but.883 Adam Ford: Reminds me of the Internet.885 Aaron Sloman: Well, yes; he invented ... it was just extraordinary886 that he was able to do that, before most of the components that we887 need for it existed.889 Adam Ford: [Another person who did that] was Vernor Vinge [] /True890 Names/.892 Aaron Sloman: When was that written?894 Adam Ford: The seventies.896 Aaron Sloman: Okay, well a lot of the technology was already around897 then. The original bits of internet were working, in about 1973, I was898 sitting ... 1974, I was sitting at Sussex University trying to899 use...learn LOGO, the programming language, to decide whether it was900 going to be useful for teaching AI, and I was sitting [] paper901 teletype, there was paper coming out, transmitting ten characters a902 second from Sussex to UCL computer lab by telegraph cable, from there903 to somewhere in Norway via another cable, from there by satellite to904 California to a computer Xerox [] research center where they had905 implemented a computer with a LOGO system on it, with someone I had906 met previously in Edinburgh, Danny Bobrow, and he allowed me to have907 access to this sytem. So there I was typing. And furthermore, it was908 duplex typing, so every character I typed didn't show up on my909 terminal until it had gone all the way there and echoed back, so I910 would type, and the characters would come back four seconds later.912 [55:26] But that was the Internet, and I think Vernor Vinge was913 writing after that kind of thing had already started, but I don't914 know. Anyway.916 [55:41] Another...I mentioned H.G. Wells, /The Time Machine/. I917 recently discovered, because [[http://en.wikipedia.org/wiki/David_Lodge_(author)][David Lodge]] had written a sort of918 semi-novel about him, that he had invented Wikipedia, in advance--- he919 had this notion of an encyclopedia that was free to everybody, and920 everybody could contribute and [collaborate on it]. So, go to the921 science fiction writers to find out the future --- well, a range of922 possible futures.924 Adam Ford: Well the thing is with science fiction writers, they have925 to maintain some sort of interest for their readers, after all the926 science fiction which reaches us is the stuff that publishers want to927 sell, and so there's a little bit of a ... a bias towards making a928 plot device there, and so the dramatic sort of appeals to our929 amygdala, our lizard brain; we'll sort of stay there obviously to some930 extent. But I think that they do come up with sort of amazing ideas; I931 think it's worth trying to make these predictions; I think that we932 should more time on strategic forecasting, I mean take that seriously.934 Aaron Sloman: Well, I'm happy to leave that to others; I just want to935 try to understand these problems that bother me about how things936 work. And it may be that some would say that's irresponsible if I937 don't think about what the implications will be. Well, understanding938 how humans work /might/ enable us to make [] humans --- I suspect it939 wont happen in this century; I think it's going to be too difficult.