Mercurial > thoughts
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adding more recommendations from loose sheets.
author | Robert McIntyre <rlm@mit.edu> |
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date | Mon, 26 May 2014 02:19:52 -0400 |
parents | a72ac82bb785 |
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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_QUOTE23 *Editor's note:* This is a working draft transcript which I made of24 [[http://www.youtube.com/watch?feature=player_detailpage&v=iuH8dC7Snno][this nice interview]] of Aaron Sloman. Having just finished one25 iteration of transcription, I still need to go in and clean up the26 formatting and fix the parts that I misheard, so you can expect the27 text to improve significantly in the near future.29 To the extent that this is my work, you have my permission to make30 copies of this transcript for your own purposes. Also, feel free to31 e-mail me with comments or corrections.33 You can send mail to =transcript@aurellem.org=.35 Cheers,37 ---Dylan38 #+END_QUOTE42 * Introduction44 ** Aaron Sloman evolves into a philosopher of AI45 [0:09] My name is Aaron Sloman. My first degree many years ago in46 Capetown University was in Physics and Mathematics, and I intended to47 go and be a mathematician. I came to Oxford and encountered48 philosophers --- I had started reading philosophy and discussing49 philosophy before then, and then I found that there were philosophers50 who said things about mathematics that I thought were wrong, so51 gradually got more and more involved in [philosophy] discussions and52 switched to doing philosophy DPhil. Then I became a philosophy53 lecturer and about six years later, I was introduced to artificial54 intelligence when I was a lecturer at Sussex University in philosophy55 and I very soon became convinced that the best way to make progress in56 both areas of philosophy (including philosophy of mathematics which I57 felt i hadn't dealt with adequately in my DPhil) about the philosophy58 of mathematics, philosophy of mind, philsophy of language and all59 those things---the best way was to try to design and test working60 fragments of mind and maybe eventually put them all together but61 initially just working fragments that would do various things.63 [1:12] And I learned to program and ~ with various other people64 including ~Margaret Boden whom you've interviewed, developed---helped65 develop an undergraduate degree in AI and other things and also began66 to do research in AI and so on which I thought of as doing philosophy,67 primarily.69 [1:29] And then I later moved to the University of Birmingham and I70 was there --- I came in 1991 --- and I've been retired for a while but71 I'm not interested in golf or gardening so I just go on doing full72 time research and my department is happy to keep me on without paying73 me and provide space and resources and I come, meeting bright people74 at conferences and try to learn and make progress if I can.76 ** AI is hard, in part because there are tempting non-problems.78 One of the things I learnt and understood more and more over the many79 years --- forty years or so since I first encountered AI --- is how80 hard the problems are, and in part that's because it's very often81 tempting to /think/ the problem is something different from what it82 actually is, and then people design solutions to the non-problems, and83 I think of most of my work now as just helping to clarify what the84 problems are: what is it that we're trying to explain --- and maybe85 this is leading into what you wanted to talk about:87 I now think that one of the ways of getting a deep understanding of88 that is to find out what were the problems that biological evolution89 solved, because we are a product of /many/ solutions to /many/90 problems, and if we just try to go in and work out what the whole91 system is doing, we may get it all wrong, or badly wrong.94 * What problems of intelligence did evolution solve?96 ** Intelligence consists of solutions to many evolutionary problems; no single development (e.g. communication) was key to human-level intelligence.98 [2:57] Well, first I would challenge that we are the dominant99 species. I know it looks like that but actually if you count biomass,100 if you count number of species, if you count number of individuals,101 the dominant species are microbes --- maybe not one of them but anyway102 they're the ones who dominate in that sense, and furthermore we are103 mostly --- we are largely composed of microbes, without which we104 wouldn't survive.107 # ** Many nonlinguistic competences require sophisticated internal representations108 [3:27] But there are things that make humans (you could say) best at109 those things, or worst at those things, but it's a combination. And I110 think it was a collection of developments of which there isn't any111 single one. [] there might be, some people say, human language which112 changed everything. By our human language, they mean human113 communication in words, but I think that was a later development from114 what must have started as the use of /internal/ forms of115 representation --- which are there in nest-building birds, in116 pre-verbal children, in hunting mammals --- because you can't take in117 information about a complex structured environment in which things can118 change and you may have to be able to work out what's possible and119 what isn't possible, without having some way of representing the120 components of the environment, their relationships, the kinds of121 things they can and can't do, the kinds of things you might or might122 not be able to do --- and /that/ kind of capability needs internal123 languages, and I and colleagues [at Birmingham] have been referring to124 them as generalized languages because some people object to125 referring...to using language to refer to something that isn't used126 for communication. But from that viewpoint, not only humans but many127 other animals developed abilities to do things to their environment to128 make them more friendly to themselves, which depended on being able to129 represent possible futures, possible actions, and work out what's the130 best thing to do.132 [5:13] And nest-building in corvids for instance---crows, magpies,133 [hawks], and so on --- are way beyond what current robots can do, and134 in fact I think most humans would be challenged if they had to go and135 find a collection of twigs, one at a time, maybe bring them with just136 one hand --- or with your mouth --- and assemble them into a137 structure that, you know, is shaped like a nest, and is fairly rigid,138 and you could trust your eggs in them when wind blows. But they're139 doing it, and so ... they're not our evolutionary ancestors, but140 they're an indication --- and that example is an indication --- of141 what must have evolved in order to provide control over the142 environment in /that/ species.144 ** Speculation about how communication might have evolved from internal lanagues.145 [5:56] And I think hunting mammals, fruit-picking mammals, mammals146 that can rearrange parts of the environment, provide shelters, needed147 to have .... also needed to have ways of representing possible148 futures, not just what's there in the environment. I think at a later149 stage, that developed into a form of communication, or rather the150 /internal/ forms of representation became usable as a basis for151 providing [context] to be communicated. And that happened, I think,152 initially through performing actions that expressed intentions, and153 probably led to situtations where an action (for instance, moving some154 large object) was performed more easily, or more successfully, or more155 accurately if it was done collaboratively. So someone who had worked156 out what to do might start doing it, and then a conspecific might be157 able to work out what the intention is, because that person has the158 /same/ forms of representation and can build theories about what's159 going on, and might then be able to help.161 [7:11] You can imagine that if that started happening more (a lot of162 collaboration based on inferred intentions and plans) then sometimes163 the inferences might be obscure and difficult, so the /actions/ might164 be enhanced to provide signals as to what the intention is, and what165 the best way is to help, and so on.167 [7:35] So, this is all handwaving and wild speculation, but I think168 it's consistent with a large collection of facts which one can look at169 --- and find if one looks for them, but one won't know if [some]one170 doesn't look for them --- about the way children, for instance, who171 can't yet talk, communicate, and the things they'll do, like going to172 the mother and turning the face to point in the direction where the173 child wants it to look and so on; that's an extreme version of action174 indicating intention.176 [8:03] Anyway. That's a very long roundabout answer to one conjecture177 that the use of communicative language is what gave humans their178 unique power to create and destroy and whatever, and I'm saying that179 if by that you mean /communicative/ language, then I'm saying there180 was something before that which was /non/-communicative language, and I181 suspect that noncommunicative language continues to play a deep role182 in /all/ human perception ---in mathematical and scientific reasoning, in183 problem solving --- and we don't understand very much about it.185 [8:48]186 I'm sure there's a lot more to be said about the development of187 different kinds of senses, the development of brain structures and188 mechanisms is above all that, but perhaps I've droned on long enough189 on that question.192 * How do language and internal states relate to AI?194 [9:09] Well, I think most of the human and animal capabilities that195 I've been referring to are not yet to be found in current robots or196 [computing] systems, and I think there are two reasons for that: one197 is that it's intrinsically very difficult; I think that in particular198 it may turn out that the forms of information processing that one can199 implement on digital computers as we currently know them may not be as200 well suited to performing some of these tasks as other kinds of201 computing about which we don't know so much --- for example, I think202 there may be important special features about /chemical/ computers203 which we might [talk about in a little bit? find out about].205 ** In AI, false assumptions can lead investigators astray.206 [9:57] So, one of the problems then is that the tasks are hard ... but207 there's a deeper problem as to why AI hasn't made a great deal of208 progress on these problems that I'm talking about, and that is that209 most AI researchers assume things---and this is not just AI210 researchers, but [also] philsophers, and psychologists, and people211 studying animal behavior---make assumptions about what it is that212 animals or humans do, for instance make assumptions about what vision213 is for, or assumptions about what motivation is and how motivation214 works, or assumptions about how learning works, and then they try ---215 the AI people try --- to model [or] build systems that perform those216 assumed functions. So if you get the /functions/ wrong, then even if217 you implement some of the functions that you're trying to implement,218 they won't necessarily perform the tasks that the initial objective219 was to imitate, for instance the tasks that humans, and nest-building220 birds, and monkeys and so on can perform.222 ** Example: Vision is not just about finding surfaces, but about finding affordances.223 [11:09] I'll give you a simple example --- well, maybe not so simple,224 but --- It's often assumed that the function of vision in humans (and225 in other animals with good eyesight and so on) is to take in optical226 information that hits the retina, and form into the (maybe changing227 --- or, really, in our case definitely changing) patterns of228 illumination where there are sensory receptors that detect those229 patterns, and then somehow from that information (plus maybe other230 information gained from head movement or from comparisons between two231 eyes) to work out what there was in the environment that produced232 those patterns, and that is often taken to mean \ldquo{}where were the233 surfaces off which the light bounced before it came to me\rdquo{}. So234 you essentially think of the task of the visual system as being to235 reverse the image formation process: so the 3D structure's there, the236 lens causes the image to form in the retina, and then the brain goes237 back to a model of that 3D structure there. That's a very plausible238 theory about vision, and it may be that that's a /subset/ of what239 human vision does, but I think James Gibson pointed out that that kind240 of thing is not necessarily going to be very useful for an organism,241 and it's very unlikely that that's the main function of perception in242 general, namely to produce some physical description of what's out243 there.245 [12:37] What does an animal /need/? It needs to know what it can do,246 what it can't do, what the consequences of its actions will be247 .... so, he introduced the word /affordance/, so from his point of248 view, the function of vision, perception, are to inform the organism249 of what the /affordances/ are for action, where that would mean what250 the animal, /given/ its morphology (what it can do with its mouth, its251 limbs, and so on, and the ways it can move) what it can do, what its252 needs are, what the obstacles are, and how the environment supports or253 obstructs those possible actions.255 [13:15] And that's a very different collection of information256 structures that you need from, say, \ldquo{}where are all the257 surfaces?\rdquo{}: if you've got all the surfaces, /deriving/ the258 affordances would still be a major task. So, if you think of the259 perceptual system as primarily (for biological organisms) being260 devices that provide information about affordances and so on, then the261 tasks look very different. And most of the people working, doing262 research on computer vision in robots, I think haven't taken all that263 on board, so they're trying to get machines to do things which, even264 if they were successful, would not make the robots very intelligent265 (and in fact, even the ones they're trying to do are not really easy266 to do, and they don't succeed very well--- although, there's progress;267 I shouldn't disparage it too much.)269 ** Online and offline intelligence271 [14:10] It gets more complex as animals get more sophisticated. So, I272 like to make a distinction between online intelligence and offline273 intelligence. So, for example, if I want to pick something up --- like274 this leaf <he plucks a leaf from the table> --- I was able to select275 it from all the others in there, and while moving my hand towards it,276 I was able to guide its trajectory, making sure it was going roughly277 in the right direction --- as opposed to going out there, which278 wouldn't have been able to pick it up --- and these two fingers ended279 up with a portion of the leaf between them, so that I was able to tell280 when I'm ready to do that <he clamps the leaf between two fingers>281 and at that point, I clamped my fingers and then I could pick up the282 leaf.284 [14:54] Whereas, --- and that's an example of online intelligence:285 during the performance of an action (both from the stage where it's286 initiated, and during the intermediate stages, and where it's287 completed) I'm taking in information relevant to controlling all those288 stages, and that relevant information keeps changing. That means I289 need stores of transient information which gets discarded almost290 immediately and replaced or something. That's online intelligence. And291 there are many forms; that's just one example, and Gibson discussed292 quite a lot of examples which I won't try to replicate now.294 [15:30] But in offline intelligence, you're not necessarily actually295 /performing/ the actions when you're using your intelligence; you're296 thinking about /possible/ actions. So, for instance, I could think297 about how fast or by what route I would get back to the lecture room298 if I wanted to [get to the next talk] or something. And I know where299 the door is, roughly speaking, and I know roughly which route I would300 take, when I go out, I should go to the left or to the right, because301 I've stored information about where the spaces are, where the302 buildings are, where the door was that we came out --- but in using303 that information to think about that route, I'm not actually304 performing the action. I'm not even /simulating/ it in detail: the305 precise details of direction and speed and when to clamp my fingers,306 or when to contract my leg muscles when walking, are all irrelevant to307 thinking about a good route, or thinking about the potential things308 that might happen on the way. Or what would be a good place to meet309 someone who I think [for an acquaintance in particular] --- [barber]310 or something --- I don't necessarily have to work out exactly /where/311 the person's going to stand, or from what angle I would recognize312 them, and so on.314 [16:46] So, offline intelligence --- which I think became not just a315 human competence; I think there are other animals that have aspects of316 it: Squirrels are very impressive as you watch them. Gray squirrels at317 any rate, as you watch them defeating squirrel-proof birdfeeders, seem318 to have a lot of that [offline intelligence], as well as the online319 intelligence when they eventually perform the action they've worked320 out [] that will get them to the nuts.322 [17:16] And I think that what happened during our evolution is that323 mechanisms for acquiring and processing and storing and manipulating324 information that is more and more remote from the performance of325 actions developed. An example is taking in information about where326 locations are that you might need to go to infrequently: There's a327 store of a particular type of material that's good for building on328 roofs of houses or something out around there in some329 direction. There's a good place to get water somewhere in another330 direction. There are people that you'd like to go and visit in331 another place, and so on.333 [17:59] So taking in information about an extended environment and334 building it into a structure that you can make use of for different335 purposes is another example of offline intelligence. And when we do336 that, we sometimes use only our brains, but in modern times, we also337 learned how to make maps on paper and walls and so on. And it's not338 clear whether the stuff inside our heads has the same structures as339 the maps we make on paper: the maps on paper have a different340 function; they may be used to communicate with others, or meant for341 /looking/ at, whereas the stuff in your head you don't /look/ at; you342 use it in some other way.344 [18:46] So, what I'm getting at is that there's a great deal of human345 intelligence (and animal intelligence) which is involved in what's346 possible in the future, what exists in distant places, what might have347 happened in the past (sometimes you need to know why something is as348 it is, because that might be relevant to what you should or shouldn't349 do in the future, and so on), and I think there was something about350 human evolution that extended that offline intelligence way beyond351 that of animals. And I don't think it was /just/ human language, (but352 human language had something to do with it) but I think there was353 something else that came earlier than language which involves the354 ability to use your offline intelligence to discover something that355 has a rich mathematical structure.357 ** Example: Even toddlers use sophisticated geometric knowledge358 #+<<example-gap>>359 [19:44] I'll give you a simple example: if you look through a gap, you360 can see something that's on the other side of the gap. Now, you361 /might/ see what you want to see, or you might see only part of it. If362 you want to see more of it, which way would you move? Well, you could363 either move /sideways/, and see through the gap---and see it roughly364 the same amount but a different part of it [if it's a ????], or you365 could move /towards/ the gap and then your view will widen as you366 approach the gap. Now, there's a bit of mathematics in there, insofar367 as you are implicitly assuming that information travels in straight368 lines, and as you go closer to a gap, the straight lines that you can369 draw from where you are through the gap, widen as you approach that370 gap. Now, there's a kind of theorem of Euclidean geometry in there371 which I'm not going to try to state very precisely (and as far as I372 know, wasn't stated explicitly in Euclidean geometry) but it's373 something every toddler--- human toddler---learns. (Maybe other374 animals also know it, I don't know.) But there are many more things,375 actions to perform, to get you more information about things, actions376 to perform to conceal information from other people, actions that will377 enable you to operate, to act on a rigid object in one place in order378 to produce an effect on another place. So, there's a lot of stuff that379 involves lines and rotations and angles and speeds and so on that I380 think humans (maybe, to a lesser extent, other animals) develop the381 ability to think about in a generic way. That means that you could382 take out the generalizations from the particular contexts and then383 re-use them in a new contexts in ways that I think are not yet384 represented at all in AI and in theories of human learning in any []385 way --- although some people are trying to study learning of mathematics.387 * Animal intelligence389 ** The priority is /cataloguing/ what competences have evolved, not ranking them.390 [22:03] I wasn't going to challenge the claim that humans can do more391 sophisticated forms of [tracking], just to mention that there are some392 things that other animals can do which are in some ways comparable,393 and some ways superior to [things] that humans can do. In particular,394 there are species of birds and also, I think, some rodents ---395 squirrels, or something --- I don't know enough about the variety ---396 that can hide nuts and remember where they've hidden them, and go back397 to them. And there have been tests which show that some birds are able398 to hide tens --- you know, [eighteen] or something nuts --- and to399 remember which ones have been taken, which ones haven't, and so400 on. And I suspect most humans can't do that. I wouldn't want to say401 categorically that maybe we couldn't, because humans are very402 [varied], and also [a few] people can develop particular competences403 through training. But it's certainly not something I can do.406 ** AI can be used to test philosophical theories407 [23:01] But I also would like to say that I am not myself particularly408 interested in trying to align animal intelligences according to any409 kind of scale of superiority; I'm just trying to understand what it410 was that biological evolution produced, and how it works, and I'm411 interested in AI /mainly/ because I think that when one comes up with412 theories about how these things work, one needs to have some way of413 testing the theory. And AI provides ways of implementing and testing414 theories that were not previously available: Immanuel Kant was trying415 to come up with theories about how minds work, but he didn't have any416 kind of a mechanism that he could build to test his theory about the417 nature of mathematical knowledge, for instance, or how concepts were418 developed from babyhood onward. Whereas now, if we do develop a419 theory, we have a criterion of adequacy, namely it should be precise420 enough and rich enough and detailed to enable a model to be421 built. And then we can see if it works.423 [24:07] If it works, it doesn't mean we've proved that the theory is424 correct; it just shows it's a candidate. And if it doesn't work, then425 it's not a candidate as it stands; it would need to be modified in426 some way.428 * Is abstract general intelligence feasible?430 ** It's misleading to compare the brain and its neurons to a computer made of transistors431 [24:27] I think there's a lot of optimism based on false clues:432 the...for example, one of the false clues is to count the number of433 neurons in the brain, and then talk about the number of transistors434 you can fit into a computer or something, and then compare them. It435 might turn out that the study of the way synapses work (which leads436 some people to say that a typical synapse [] in the human brain has437 computational power comparable to the Internet a few years ago,438 because of the number of different molecules that are doing things,439 the variety of types of things that are being done in those molecular440 interactions, and the speed at which they happen, if you somehow count441 up the number of operations per second or something, then you get442 these comparable figures).444 ** For example, brains may rely heavily on chemical information processing445 Now even if the details aren't right, there may just be a lot of446 information processing that...going on in brains at the /molecular/447 level, not the neural level. Then, if that's the case, the processing448 units will be orders of magnitude larger in number than the number of449 neurons. And it's certainly the case that all the original biological450 forms of information processing were chemical; there weren't brains451 around, and still aren't in most microbes. And even when humans grow452 their brains, the process of starting from a fertilized egg and453 producing this rich and complex structure is, for much of the time,454 under the control of chemical computations, chemical information455 processing---of course combined with physical sorts of materials and456 energy and so on as well.458 [26:25] So it would seem very strange if all that capability was459 something thrown away when you've got a brain and all the information460 processing, the [challenges that were handled in making a brain],461 ... This is handwaving on my part; I'm just saying that we /might/462 learn that what brains do is not what we think they do, and that463 problems of replicating them are not what we think they are, solely in464 terms of numerical estimate of time scales, the number of components,465 and so on.467 ** Brain algorithms may simply be optimized for certain kinds of information processing other than bit manipulations468 [26:56] But apart from that, the other basis of skepticism concerns469 how well we understand what the problems are. I think there are many470 people who try to formalize the problems of designing an intelligent471 system in terms of streams of information thought of as bit streams or472 collections of bit streams, and they think of as the problems of473 intelligence as being the construction or detection of patterns in474 those, and perhaps not just detection of patterns, but detection of475 patterns that are useable for sending /out/ streams to control motors476 and so on in order to []. And that way of conceptualizing the problem477 may lead on the one hand to oversimplification, so that the things478 that /would/ be achieved, if those goals were achieved, maybe much479 simpler, in some ways inadequate. Or the replication of human480 intelligence, or the matching of human intelligence---or for that481 matter, squirrel intelligence---but in another way, it may also make482 the problem harder: it may be that some of the kinds of things that483 biological evolution has achieved can't be done that way. And one of484 the ways that might turn out to be the case is not because it's not485 impossible in principle to do some of the information processing on486 artificial computers-based-on-transistors and other bit-manipulating487 []---but it may just be that the computational complexity of solving488 problems, processes, or finding solutions to complex problems, are489 much greater and therefore you might need a much larger universe than490 we have available in order to do things.492 ** Example: find the shortest path by dangling strings493 [28:55] Then if the underlying mechanisms were different, the494 information processing mechanisms, they might be better tailored to495 particular sorts of computation. There's a [] example, which is496 finding the shortest route if you've got a collection of roads, and497 they may be curved roads, and lots of tangled routes from A to B to C,498 and so on. And if you start at A and you want to get to Z --- a place499 somewhere on that map --- the process of finding the shortest route500 will involve searching through all these different possibilities and501 rejecting some that are longer than others and so on. But if you make502 a model of that map out of string, where these strings are all laid503 out on the maps and so have the lengths of the routes. Then if you504 hold the two knots in the string -- it's a network of string --- which505 correspond to the start point and end point, then /pull/, then the506 bits of string that you're left with in a straight line will give you507 the shortest route, and that process of pulling just gets you the508 solution very rapidly in a parallel computation, where all the others509 just hang by the wayside, so to speak.511 ** In sum, we know surprisingly little about the kinds of problems that evolution solved, and the manner in which they were solved.512 [30:15] Now, I'm not saying brains can build networks of string and513 pull them or anything like that; that's just an illustration of how if514 you have the right representation, correctly implemented---or suitably515 implemented---for a problem, then you can avoid very combinatorially516 complex searches, which will maybe grow exponentially with the number517 of components in your map, whereas with this thing, the time it takes518 won't depend on how many strings you've [got on the map]; you just519 pull, and it will depend only on the shortest route that exists in520 there. Even if that shortest route wasn't obvious on the original map.523 [30:59] So that's a rather long-winded way of formulating the524 conjecture which---of supporting, a roundabout way of supporting the525 conjecture that there may be something about the way molecules perform526 computations where they have the combination of continuous change as527 things move through space and come together and move apart, and528 whatever --- and also snap into states that then persist, so [as you529 learn from] quantum mechanics, you can have stable molecular530 structures which are quite hard to separate, and then in catalytic531 processes you can separate them, or extreme temperatures, or strong532 forces, but they may nevertheless be able to move very rapidly in some533 conditions in order to perform computations.535 [31:49] Now there may be things about that kind of structure that536 enable searching for solutions to /certain/ classes of problems to be537 done much more efficiently (by brain) than anything we could do with538 computers. It's just an open question.540 [32:04] So it /might/ turn out that we need new kinds of technology541 that aren't on the horizon in order to replicate the functions that542 animal brains perform ---or, it might not. I just don't know. I'm not543 claiming that there's strong evidence for that; I'm just saying that544 it might turn out that way, partly because I think we know less than545 many people think we know about what biological evolution achieved.547 [32:28] There are some other possibilities: we may just find out that548 there are shortcuts no one ever thought of, and it will all happen549 much more quickly---I have an open mind; I'd be surprised, but it550 could turn up. There /is/ something that worries me much more than the551 singularity that most people talk about, which is machines achieving552 human-level intelligence and perhaps taking over [the] planet or553 something. There's what I call the /singularity of cognitive554 catch-up/ ...556 * A singularity of cognitive catch-up558 ** What if it will take a lifetime to learn enough to make something new?559 ... SCC, singularity of cognitive catch-up, which I think we're close560 to, or maybe have already reached---I'll explain what I mean by561 that. One of the products of biological evolution---and this is one of562 the answers to your earlier questions which I didn't get on to---is563 that humans have not only the ability to make discoveries that none of564 their ancestors have ever made, but to shorten the time required for565 similar achievements to be reached by their offspring and their566 descendants. So once we, for instance, worked out ways of complex567 computations, or ways of building houses, or ways of finding our way568 around, we don't need...our children don't need to work it out for569 themselves by the same lengthy trial and error procedure; we can help570 them get there much faster.572 Okay, well, what I've been referring to as the singularity of573 cognitive catch-up depends on the fact that---fairly obvious, and it's574 often been commented on---that in case of humans, it's not necessary575 for each generation to learn what previous generations learned /in the576 same way/. And we can speed up learning once something has been577 learned, [it is able to] be learned by new people. And that has meant578 that the social processes that support that kind of education of the579 young can enormously accelerate what would have taken...perhaps580 thousands [or] millions of years for evolution to produce, can happen in581 a much shorter time.584 [34:54] But here's the catch: in order for a new advance to happen ---585 so for something new to be discovered that wasn't there before, like586 Newtonian mechanics, or the theory of relativity, or Beethoven's music587 or [style] or whatever --- the individuals have to have traversed a588 significant amount of what their ancestors have learned, even if they589 do it much faster than their ancestors, to get to the point where they590 can see the gaps, the possibilities for going further than their591 ancestors, or their parents or whatever, have done.593 [35:27] Now in the case of knowledge of science, mathematics,594 philosophy, engineering and so on, there's been a lot of accumulated595 knowledge. And humans are living a /bit/ longer than they used to, but596 they're still living for [whatever it is], a hundred years, or for597 most people, less than that. So you can imagine that there might come598 a time when in a normal human lifespan, it's not possible for anyone599 to learn enough to understand the scope and limits of what's already600 been achieved in order to see the potential for going beyond it and to601 build on what's already been done to make that...those future steps.603 [36:10] So if we reach that stage, we will have reached the604 singularity of cognitive catch-up because the process of education605 that enables individuals to learn faster than their ancestors did is606 the catching-up process, and it may just be that we at some point607 reach a point where catching up can only happen within a lifetime of608 an individual, and after that they're dead and they can't go609 beyond. And I have some evidence that there's a lot of that around610 because I see a lot of people coming up with what /they/ think of as611 new ideas which they've struggled to come up with, but actually they612 just haven't taken in some of what was...some of what was done [] by613 other people, in other places before them. And I think that despite614 the availability of search engines which make it /easier/ for people615 to get the information---for instance, when I was a student, if I616 wanted to find out what other people had done in the field, it was a617 laborious process---going to the library, getting books, and618 ---whereas now, I can often do things in seconds that would have taken619 hours. So that means that if seconds [are needed] for that kind of620 work, my lifespan has been extended by a factor of ten or621 something. So maybe that /delays/ the singularity, but it may not622 delay it enough. But that's an open question; I don't know. And it may623 just be that in some areas, this is more of a problem than others. For624 instance, it may be that in some kinds of engineering, we're handing625 over more and more of the work to machines anyways and they can go on626 doing it. So for instance, most of the production of computers now is627 done by a computer-controlled machine---although some of the design628 work is done by humans--- a lot of /detail/ of the design is done by629 computers, and they produce the next generation, which then produces630 the next generation, and so on.632 [37:57] I don't know if humans can go on having major advances, so633 it'll be kind of sad if we can't.635 * Spatial reasoning: a difficult problem637 [38:15] Okay, well, there are different problems [ ] mathematics, and638 they have to do with properties. So for instance a lot of mathematics639 that can be expressed in terms of logical structures or algebraic640 structures and those are pretty well suited for manipulation and...on641 computers, and if a problem can be specified using the642 logical/algebraic notation, and the solution method requires creating643 something in that sort of notation, then computers are pretty good,644 and there are lots of mathematical tools around---there are theorem645 provers and theorem checkers, and all kinds of things, which couldn't646 have existed fifty, sixty years ago, and they will continue getting647 better.650 But there was something that I was [[example-gap][alluding to earlier]] when I gave the651 example of how you can reason about what you will see by changing your652 position in relation to a door, where what you are doing is using your653 grasp of spatial structures and how as one spatial relationship654 changes namely you come closer to the door or move sideways and655 parallel to the wall or whatever, other spatial relationships change656 in parallel, so the lines from your eyes through to other parts of657 the...parts of the room on the other side of the doorway change,658 spread out more as you go towards the doorway, and as you move659 sideways, they don't spread out differently, but focus on different660 parts of the internal ... that they access different parts of the661 ... of the room.663 Now, those are examples of ways of thinking about relationships and664 changing relationships which are not the same as thinking about what665 happens if I replace this symbol with that symbol, or if I substitute666 this expression in that expression in a logical formula. And at the667 moment, I do not believe that there is anything in AI amongst the668 mathematical reasoning community, the theorem-proving community, that669 can model the processes that go on when a young child starts learning670 to do Euclidean geometry and is taught things about---for instance, I671 can give you a proof that the angles of any triangle add up to a672 straight line, 180 degrees.674 ** Example: Spatial proof that the angles of any triangle add up to a half-circle675 There are standard proofs which involves starting with one triangle,676 then adding a line parallel to the base one of my former students,677 Mary Pardoe, came up with which I will demonstrate with this <he holds678 up a pen> --- can you see it? If I have a triangle here that's got679 three sides, if I put this thing on it, on one side --- let's say the680 bottom---I can rotate it until it lies along the second...another681 side, and then maybe move it up to the other end ~. Then I can rotate682 it again, until it lies on the third side, and move it back to the683 other end. And then I'll rotate it again and it'll eventually end up684 on the original side, but it will have changed the direction it's685 pointing in --- and it won't have crossed over itself so it will have686 gone through a half-circle, and that says that the three angles of a687 triangle add up to the rotations of half a circle, which is a688 beautiful kind of proof and almost anyone can understand it. Some689 mathematicians don't like it, because they say it hides some of the690 assumptions, but nevertheless, as far as I'm concerned, it's an691 example of a human ability to do reasoning which, once you've692 understood it, you can see will apply to any triangle --- it's got to693 be a planar triangle --- not a triangle on a globe, because then the694 angles can add up to more than ... you can have three /right/ angles695 if you have an equator...a line on the equator, and a line going up to696 to the north pole of the earth, and then you have a right angle and697 then another line going down to the equator, and you have a right698 angle, right angle, right angle, and they add up to more than a699 straight line. But that's because the triangle isn't in the plane,700 it's on a curved surface. In fact, that's one of the701 differences...definitional differences you can take between planar and702 curved surfaces: how much the angles of a triangle add up to. But our703 ability to /visualize/ and notice the generality in that process, and704 see that you're going to be able to do the same thing using triangles705 that stretch in all sorts of ways, or if it's a million times as706 large, or if it's made...you know, written on, on...if it's drawn in707 different colors or whatever --- none of that's going to make any708 difference to the essence of that process. And that ability to see709 the commonality in a spatial structure which enables you to draw some710 conclusions with complete certainty---subject to the possibility that711 sometimes you make mistakes, but when you make mistakes, you can712 discover them, as has happened in the history of geometrical theorem713 proving. Imre Lakatos had a wonderful book called [[http://en.wikipedia.org/wiki/Proofs_and_Refutations][/Proofs and714 Refutations/]] --- which I won't try to summarize --- but he has715 examples: mistakes were made; that was because people didn't always716 realize there were subtle subcases which had slightly different717 properties, and they didn't take account of that. But once they're718 noticed, you rectify that.720 ** Geometric results are fundamentally different than experimental results in chemistry or physics.721 [43:28] But it's not the same as doing experiments in chemistry and722 physics, where you can't be sure it'll be the same on [] or at a high723 temperature, or in a very strong magnetic field --- with geometric724 reasoning, in some sense you've got the full information in front of725 you; even if you don't always notice an important part of it. So, that726 kind of reasoning (as far as I know) is not implemented anywhere in a727 computer. And most people who do research on trying to model728 mathematical reasoning, don't pay any attention to that, because of729 ... they just don't think about it. They start from somewhere else,730 maybe because of how they were educated. I was taught Euclidean731 geometry at school. Were you?733 (Adam ford: Yeah)735 Many people are not now. Instead they're taught set theory, and736 logic, and arithmetic, and [algebra], and so on. And so they don't use737 that bit of their brains, without which we wouldn't have built any of738 the cathedrals, and all sorts of things we now depend on.740 * Is near-term artificial general intelligence likely?742 ** Two interpretations: a single mechanism for all problems, or many mechanisms unified in one program.744 [44:35] Well, this relates to what's meant by general. And when I745 first encountered the AGI community, I thought that what they all746 meant by general intelligence was /uniform/ intelligence ---747 intelligence based on some common simple (maybe not so simple, but)748 single powerful mechanism or principle of inference. And there are749 some people in the community who are trying to produce things like750 that, often in connection with algorithmic information theory and751 computability of information, and so on. But there's another sense of752 general which means that the system of general intelligence can do753 lots of different things, like perceive things, understand language,754 move around, make things, and so on --- perhaps even enjoy a joke;755 that's something that's not nearly on the horizon, as far as I756 know. Enjoying a joke isn't the same as being able to make laughing757 noises.759 Given, then, that there are these two notions of general760 intelligence---there's one that looks for one uniform, possibly761 simple, mechanism or collection of ideas and notations and algorithms,762 that will deal with any problem that's solvable --- and the other763 that's general in the sense that it can do lots of different things764 that are combined into an integrated architecture (which raises lots765 of questions about how you combine these things and make them work766 together) and we humans, certainly, are of the second kind: we do all767 sorts of different things, and other animals also seem to be of the768 second kind, perhaps not as general as humans. Now, it may turn out769 that in some near future time, who knows---decades, a few770 decades---you'll be able to get machines that are capable of solving771 in a time that will depend on the nature of the problem, but any772 problem that is solvable, and they will be able to do it in some sort773 of tractable time --- of course, there are some problems that are774 solvable that would require a larger universe and a longer history775 than the history of the universe, but apart from that constraint,776 these machines will be able to do anything []. But to be able to do777 some of the kinds of things that humans can do, like the kinds of778 geometrical reasoning where you look at the shape and you abstract779 away from the precise angles and sizes and shapes and so on, and780 realize there's something general here, as must have happened when our781 ancestors first made the discoveries that eventually put together in782 Euclidean geometry.784 It may be that that requires mechanisms of a kind that we don't know785 anything about at the moment. Maybe brains are using molecules and786 rearranging molecules in some way that supports that kind of787 reasoning. I'm not saying they are --- I don't know, I just don't see788 any simple...any obvious way to map that kind of reasoning capability789 onto what we currently do on computers. There is---and I just790 mentioned this briefly beforehand---there is a kind of thing that's791 sometimes thought of as a major step in that direction, namely you can792 build a machine (or a software system) that can represent some793 geometrical structure, and then be told about some change that's going794 to happen to it, and it can predict in great detail what'll795 happen. And this happens for instance in game engines, where you say796 we have all these blocks on the table and I'll drop one other block,797 and then [the thing] uses Newton's laws and properties of rigidity of798 the parts and the elasticity and also stuff about geometries and space799 and so on, to give you a very accurate representation of what'll800 happen when this brick lands on this pile of things, [it'll bounce and801 go off, and so on]. And you just, with more memory and more CPU power,802 you can increase the accuracy--- but that's totally different than803 looking at /one/ example, and working out what will happen in a whole804 /range/ of cases at a higher level of abstraction, whereas the game805 engine does it in great detail for /just/ this case, with /just/ those806 precise things, and it won't even know what the generalizations are807 that it's using that would apply to others []. So, in that sense, [we]808 may get AGI --- artificial general intelligence --- pretty soon, but809 it'll be limited in what it can do. And the other kind of general810 intelligence which combines all sorts of different things, including811 human spatial geometrical reasoning, and maybe other things, like the812 ability to find things funny, and to appreciate artistic features and813 other things may need forms of pattern-mechanism, and I have an open814 mind about that.816 * Abstract General Intelligence impacts818 [49:53] Well, as far as the first type's concerned, it could be useful819 for all kinds of applications --- there are people who worry about820 where there's a system that has that type of intelligence, might in821 some sense take over control of the planet. Well, humans often do822 stupid things, and they might do something stupid that would lead to823 disaster, but I think it's more likely that there would be other824 things [] lead to disaster--- population problems, using up all the825 resources, destroying ecosystems, and whatever. But certainly it would826 go on being useful to have these calculating devices. Now, as for the827 second kind of them, I don't know---if we succeeded at putting828 together all the parts that we find in humans, we might just make an829 artificial human, and then we might have some of them as your friends,830 and some of them we might not like, and some of them might become831 teachers or whatever, composers --- but that raises a question: could832 they, in some sense, be superior to us, in their learning833 capabilities, their understanding of human nature, or maybe their834 wickedness or whatever --- these are all issues in which I expect the835 best science fiction writers would give better answers than anything I836 could do, but I did once fantasize when I [back] in 1978, that perhaps837 if we achieved that kind of thing, that they would be wise, and gentle838 and kind, and realize that humans are an inferior species that, you839 know, have some good features, so they'd keep us in some kind of840 secluded...restrictive kind of environment, keep us away from841 dangerous weapons, and so on. And find ways of cohabitating with842 us. But that's just fantasy.844 Adam Ford: Awesome. Yeah, there's an interesting story /With Folded845 Hands/ where [the computers] want to take care of us and want to846 reduce suffering and end up lobotomizing everybody [but] keeping them847 alive so as to reduce the suffering.849 Aaron Sloman: Not all that different from /Brave New World/, where it850 was done with drugs and so on, but different humans are given851 different roles in that system, yeah.853 There's also /The Time Machine/, H.G. Wells, where the ... in the854 distant future, humans have split in two: the Eloi, I think they were855 called, they lived underground, they were the [] ones, and then---no,856 the Morlocks lived underground; Eloi lived on the planet; they were857 pleasant and pretty but not very bright, and so on, and they were fed858 on by ...860 Adam Ford: [] in the future.862 Aaron Sloman: As I was saying, if you ask science fiction writers,863 you'll probably come up with a wide variety of interesting answers.865 Adam Ford: I certainly have; I've spoken to [] of Birmingham, and866 Sean Williams, ... who else?868 Aaron Sloman: Did you ever read a story by E.M. Forrester called /The869 Machine Stops/ --- very short story, it's [[http://archive.ncsa.illinois.edu/prajlich/forster.html][on the Internet somewhere]]870 --- it's about a time when people sitting ... and this was written in871 about [1914 ] so it's about...over a hundred years ago ... people are872 in their rooms, they sit in front of screens, and they type things,873 and they communicate with one another that way, and they don't meet;874 they have debates, and they give lectures to their audiences that way,875 and then there's a woman whose son says \ldquo{}I'd like to see876 you\rdquo{} and she says \ldquo{}What's the point? You've got me at877 this point \rdquo{} but he wants to come and talk to her --- I won't878 tell you how it ends, but.880 Adam Ford: Reminds me of the Internet.882 Aaron Sloman: Well, yes; he invented ... it was just extraordinary883 that he was able to do that, before most of the components that we884 need for it existed.886 Adam Ford: [Another person who did that] was Vernor Vinge [] /True887 Names/.889 Aaron Sloman: When was that written?891 Adam Ford: The seventies.893 Aaron Sloman: Okay, well a lot of the technology was already around894 then. The original bits of internet were working, in about 1973, I was895 sitting ... 1974, I was sitting at Sussex University trying to896 use...learn LOGO, the programming language, to decide whether it was897 going to be useful for teaching AI, and I was sitting [] paper898 teletype, there was paper coming out, transmitting ten characters a899 second from Sussex to UCL computer lab by telegraph cable, from there900 to somewhere in Norway via another cable, from there by satellite to901 California to a computer Xerox [] research center where they had902 implemented a computer with a LOGO system on it, with someone I had903 met previously in Edinburgh, Danny Bobrow, and he allowed me to have904 access to this sytem. So there I was typing. And furthermore, it was905 duplex typing, so every character I typed didn't show up on my906 terminal until it had gone all the way there and echoed back, so I907 would type, and the characters would come back four seconds later.909 [55:26] But that was the Internet, and I think Vernor Vinge was910 writing after that kind of thing had already started, but I don't911 know. Anyway.913 [55:41] Another...I mentioned H.G. Wells, /The Time Machine/. I914 recently discovered, because [[http://en.wikipedia.org/wiki/David_Lodge_(author)][David Lodge]] had written a sort of915 semi-novel about him, that he had invented Wikipedia, in advance--- he916 had this notion of an encyclopedia that was free to everybody, and917 everybody could contribute and [collaborate on it]. So, go to the918 science fiction writers to find out the future --- well, a range of919 possible futures.921 Adam Ford: Well the thing is with science fiction writers, they have922 to maintain some sort of interest for their readers, after all the923 science fiction which reaches us is the stuff that publishers want to924 sell, and so there's a little bit of a ... a bias towards making a925 plot device there, and so the dramatic sort of appeals to our926 amygdala, our lizard brain; we'll sort of stay there obviously to some927 extent. But I think that they do come up with sort of amazing ideas; I928 think it's worth trying to make these predictions; I think that we929 should more time on strategic forecasting, I mean take that seriously.931 Aaron Sloman: Well, I'm happy to leave that to others; I just want to932 try to understand these problems that bother me about how things933 work. And it may be that some would say that's irresponsible if I934 don't think about what the implications will be. Well, understanding935 how humans work /might/ enable us to make [] humans --- I suspect it936 wont happen in this century; I think it's going to be too difficult.