Richard Feynman Computer Science Lecture - Hardware, Software and Heuristics — Transcript
Full transcript
- 0:08[Music]
- 0:47[Music]
- 1:03okay what I want to tell you about is
- 1:05computers because they have computers
- 1:06all over the place and everybody's
- 1:07talking about him and using him in a
- 1:10frightened by them or else you find it
- 1:12very great assistants and so forth and I
- 1:15wanted to tell you a little bit about
- 1:17how they work what's inside him what the
- 1:19idea is what the mechanism is so that
- 1:23you're gonna get a better idea from that
- 1:25of what you can expect them to do and
- 1:27not be able to do and the so on so I
- 1:31want that's what we're doing we will
- 1:35expose what a computer really is
- 1:37actually the first aspect is you see
- 1:41there are many different kinds of
- 1:42computers there are computers that you
- 1:44can put the data in by talking to it
- 1:46even there are computers you have to
- 1:48type the data in there are computers
- 1:50that get that data from the machinery of
- 1:52an automobile or something and computer
- 1:55how much they should shift the gears so
- 1:57they have a automatic transmission but I
- 1:59mean controlled by an automatic
- 2:01computers that are you feeling how fast
- 2:03you're going and what the hill height
- 2:04strength is that called the input part
- 2:10of the computer that is the informations
- 2:12coming from different kinds of sources
- 2:13their keyboard or telephone sensors
- 2:17inside the automobile that measure
- 2:19temperature or acceleration or something
- 2:22like that and there's another aspect
- 2:24call output for example the thing that
- 2:26goes out might be the control of the
- 2:27gasoline in the automobile it might be
- 2:30to make pictures on a TV screen that you
- 2:32can read or look at it might be that it
- 2:35makes music and make sounds and so forth
- 2:37now in the plot that's the input and the
- 2:42output which makes computers look
- 2:44different is not the part I'm talking
- 2:47about there is in between the input in
- 2:50the output the input is converted to
- 2:52some electrical form then something's
- 2:55done in the computer and it spits out
- 2:57another electrical signal which is used
- 3:00for the output so for instance in the
- 3:03automobile get thing the various senses
- 3:05are sending electrical signals to a box
- 3:07which is the proper computer proper or
- 3:09the part of the computer that I'm going
- 3:11to talk about and then in the output of
- 3:13this box is other electrical
- 3:16which go to control magnets or something
- 3:18which turn on and off the gasoline or
- 3:22else control magnets which pushing it
- 3:25out a diaphragm very rapidly it makes
- 3:27sounds
- 3:28or controls the electrical currents
- 3:30running in the beam that's going all the
- 3:32time on the screen and it makes a
- 3:34picture on the screen and so on
- 3:35so what we're going to talk about which
- 3:38is really the computer proper is the
- 3:40part in middle so it's sort of we don't
- 3:43care where the stuff comes from we don't
- 3:45care where it's going on now what is the
- 3:47stuff in the middle
- 3:48that's what's manual really manufactured
- 3:51in the computer of course a real
- 3:52computer that's sold is advertised and
- 3:55it's good because it's got a big screen
- 3:57or it's got a small screen or it's got a
- 3:59tiny keyboard that your fingers are too
- 4:01big to push the buttons or it's got a
- 4:03big keyboard that has so many buttons on
- 4:04it you can't figure out which one to
- 4:06push and they have advantages and
- 4:07disadvantages which is not what we're
- 4:10talking about would talk about what's on
- 4:11the inside the central part of the
- 4:14computer proper which I'm going to call
- 4:16it the computer problem but the whole
- 4:18computer of course is the real thing
- 4:20so but we just talk about the guts in
- 4:24the middle the thinking part if you like
- 4:26to imagine that computers think but what
- 4:29is it I'd like to compare it to a filing
- 4:34system as a matter of fact I'll
- 4:36anticipate the end a computer is a
- 4:41high-class super speed nice streamlined
- 4:44filing system and I'm going to start out
- 4:47with an ordinary old-fashioned business
- 4:49filing system and that tell you ways
- 4:52that you can change it and improve it
- 4:53and so forth until it becomes a computer
- 4:56one of the miseries of life is that
- 5:01everybody names things a little bit
- 5:03wrong and so it makes everything a
- 5:06little harder to understand in the world
- 5:07than it would be if it were named
- 5:09differently computer does not primarily
- 5:12compute in the sense of doing arithmetic
- 5:15strange although they call them
- 5:17computers that's not what they primarily
- 5:19do they primarily are filing systems
- 5:24people in the computer business say
- 5:26they're not really computers they're
- 5:29data
- 5:30handlers all right that's nice data
- 5:32handlers would it be a better name
- 5:33because it gives a better idea of the
- 5:35idea of a filing system there's a lot of
- 5:37data on cards and your handler you take
- 5:39cards out look at them put them back and
- 5:40so on so that's what the computer does
- 5:42and I'm going to describe first an
- 5:45old-fashioned filing system and then
- 5:47we'll talk about how it's improved for
- 5:50how it might be improved okay
- 5:52actually it's improved to the point of
- 5:54being made automatic and make mechanical
- 5:56electrical actually and that's our
- 5:59computer and if old-fashioned filing
- 6:02system is something that many of you are
- 6:04perhaps even unfortunately familiar with
- 6:07it's a whole lot of boxes drawers cards
- 6:11and things you know which all have stuff
- 6:15numbers it and fax on them for example
- 6:18in a business that has lots of salesmen
- 6:19that maybe that does each salesman has a
- 6:21card he has his name on it and his
- 6:23address what his general salary is what
- 6:26his commission rate is how much he sold
- 6:28last month and where he lives things
- 6:31like that let's suppose and it's written
- 6:33on lots of cards because there's lots of
- 6:34salesmen in the boxes and then the
- 6:38problem for a file clerk might be for
- 6:40example a boss comes in and says would
- 6:43you figure out oh the commission rate is
- 6:46given on the cloud like a certain
- 6:47percentage and how much you sold during
- 6:49the month but now you have to figure out
- 6:50how much we have to pay him so what you
- 6:53do is you take out a card and you look
- 6:56at how much he sold that month and you
- 6:58look as commission rate you multiply the
- 7:00two numbers and you write it on the card
- 7:02and put it back and do this on card
- 7:06after card okay what does it mean you're
- 7:08taking a car then yet looking at some
- 7:11things and doing something to them that
- 7:13is looking at some data on the car the
- 7:16easiest way to think of it to simplify
- 7:18just a little bit is that we have scrap
- 7:19paper that we can erase and use again
- 7:21use again
- 7:22so we take them we rewrite the numbers
- 7:24off the card the the amounts before so
- 7:27while we're doing the multiplication we
- 7:28can do it with the numbers without
- 7:30dirtying up the card so we copy the
- 7:32numbers over and then do the
- 7:34calculations see the answer and if the
- 7:36rule is to put the result back on this
- 7:38man Scott okay so we write it on this
- 7:40car it may be that we would like to put
- 7:42this on some other car
- 7:43maybe cards about expenses that have to
- 7:46be paid or something you see so you'd
- 7:48put that somewhere else or perhaps to
- 7:51make another example that you would like
- 7:53to add together all well I'll forget
- 7:54that you want to add together all the
- 7:56money to know how much you're gonna have
- 7:57to pay out that's another example but
- 7:59they're all the same of course that you
- 8:01take that numbers from the cards and
- 8:02write them down and recalculate and put
- 8:05it back in the numbers so you have two
- 8:06kinds of three kinds of operations
- 8:08taking cards from places looking at
- 8:13information on the cloud doing something
- 8:15to the information on the card writing
- 8:18things on the card and putting the cards
- 8:20back okay actually it could be a little
- 8:24bit simpler you could say you take the
- 8:25thing out and take the information off
- 8:27the card immediately put the card back
- 8:28this save it now you do the calculation
- 8:31and when you get the answer you pull a
- 8:33particular card out that what you want
- 8:35to put the answer on it may be the same
- 8:37man's car but wherever you want to put
- 8:39the answer you take it out right at that
- 8:40put it back okay so we have two
- 8:42operations picking up a particular card
- 8:45getting data off of it doing something
- 8:47to it and then putting numbers onto
- 8:52cards from our scrap paper on different
- 8:55cards and that's all if the file clerk
- 8:57does it to take another example suppose
- 9:01that we wanted to suppose we have
- 9:03figured out or the amount of money that
- 9:04we owe each salesman and we would like
- 9:06to know how much to draw out of the bank
- 9:08in total so we need the total amount of
- 9:10all the sales then we could do that by
- 9:14having a special card goal of total card
- 9:16and writing zero on there and this is a
- 9:20way of kind of I'm talking about the
- 9:22details of what we have to do it
- 9:23everybody knows what the do you tell a
- 9:25file clerk they add the numbers but this
- 9:27is what you might do or he who's write
- 9:30zero on this particular thing called
- 9:32total sales costs in California and do
- 9:37the fine then you take the first
- 9:38salesman card you look he's not from
- 9:39California we want the total amount of
- 9:41money we have to spend in California
- 9:43salesmen all right just as an example so
- 9:46you put that one back take the next card
- 9:48is it from California put it back next
- 9:50card in California yes then the next
- 9:52instruction is to look at how much money
- 9:54you are with this man and write that by
- 9:57- what's on the total card you take the
- 9:59number that's on the total card and the
- 10:00number that's on this man's card add
- 10:02them together and write that back on to
- 10:05the total card right you're keeping the
- 10:07total running see so the next time when
- 10:09you take another card that has a number
- 10:11on it
- 10:12just take the new totally you just
- 10:13cooked up from before there was no
- 10:15trouble last time you had zero but this
- 10:17time it's getting harder ya headed ohon
- 10:19and put the Sun back on the total card
- 10:21so you see you got a kind of a steady
- 10:23thing and when you're all done going
- 10:24through all the file the total has been
- 10:26changed and changed and changed and
- 10:28changed in the last thing you read is
- 10:30the real total of all the numbers okay
- 10:31that's what the file court might do in
- 10:34that situation and now what we're going
- 10:39to try to improve the filing system to
- 10:43improve it you see we have to have a
- 10:45fairly intelligent file click a file
- 10:47click that can multiply and add and so
- 10:50on read cards get instructions from the
- 10:53boss and remember what they are
- 10:56naturally and know how to do all these
- 10:58things has to know how to where to go to
- 11:02run up and down and pick the cards out
- 11:04of the boxes and I has to read the place
- 11:06to find the cards and know where they
- 11:07are at so it's a lot of stuff well
- 11:12another one comes along we got a new
- 11:14file clerk I got a new file clerk for
- 11:16you say to me five times faster than the
- 11:20old one oh well we'll hire but you
- 11:24discover suddenly that he doesn't know
- 11:25how to do multiplication well how in the
- 11:28hell is he going to handle their finding
- 11:32the Commission's by multiplication this
- 11:34guy isn't any good but he's five times
- 11:37faster so it's very tempting if we can
- 11:39only get him to be able to multiply so
- 11:42what do you do he is sending to school
- 11:43too much waste of time better idea to
- 11:47teach him had him you tell him how to
- 11:48multiply as follows I've taught he's
- 11:50very fast at picking up cards and
- 11:52putting him down so he takes the cards
- 11:55and he looks at say two numbers and you
- 11:58tell him to look at the last end of the
- 11:59number one's an eight and one's a seven
- 12:01right then that instruction looked at
- 12:04card number 78 in a multiplication file
- 12:07when card number 78 no multiplication
- 12:10says
- 12:1056 the multiplication table which we
- 12:15worked so hard to learn in school is
- 12:16easy to put on a set of cards on each
- 12:20card which has which is labeled by a
- 12:22number let's say the card number 78 or
- 12:247/8 the card label I don't have to
- 12:27convert it to a number of card called
- 12:29multiply seven eight answers sixteen
- 12:32there's written on a card so all he has
- 12:35to do is pick up the right card he's
- 12:36very good at that and he's very fast see
- 12:38so he sees the seven eight take the
- 12:39cockpit sink okay and so it goes he
- 12:41doesn't have to know how to multiply you
- 12:43tell them a series of instructions what
- 12:45to do exactly you give him in the
- 12:47instructions as to which cards to look
- 12:49for at what time so when you say
- 12:51multiply you don't even tell them that
- 12:52your tongue look in this box now take
- 12:54that card out and write down write down
- 12:56what that one says it's so on so you see
- 12:58that we can describe multiplication as a
- 13:01definite procedure a precise procedure
- 13:05of handling numbers in a kind of a dumb
- 13:07way and things that would have to be
- 13:11memorized are never a problem
- 13:14memorization is no problem that's what a
- 13:16filing system is for that's what cards
- 13:18are for we write everything on the cards
- 13:20every damn thing is suppose you've
- 13:21learned where all this effort is written
- 13:24on a card so with cards we can make this
- 13:27fast filing clerk actually able to
- 13:30multiply of course it's slower to have
- 13:34to look up each time in the
- 13:35multiplication table because he has no
- 13:37memory were worth a damn four numbers of
- 13:39this coin so he can't even remember that
- 13:41his use of seven times eight fifty five
- 13:43times but it still has to look it up
- 13:44again so he's slower in the sense of the
- 13:48number of operations to multiply than
- 13:51the original file clerk was but he's
- 13:53really faster because altogether he
- 13:56handles the card so much faster that in
- 13:58spite of the fact that if there's a lot
- 14:00of multiplication problems he isn't five
- 14:03times faster than other Clerk but he
- 14:05might be two times faster because he
- 14:06slowed up in the process of
- 14:08multiplication so our filing clerk does
- 14:12not know how to know how to multiply
- 14:14well we'll get a faster one
- 14:17I got another one that's ten times
- 14:19faster than last night
- 14:21he can't add no problem right I mean we
- 14:25have a adding table too right no problem
- 14:30okay he's easy he's better he can't add
- 14:32he can multiply can't handle numbers at
- 14:35all but he can compare it read and check
- 14:37that what it says on the cards is the
- 14:40same he doesn't even know that these are
- 14:43numbers he sees this shape and compares
- 14:46it to this shape and takes the cards out
- 14:48according to the instructions okay now
- 14:51where does he get his instructions
- 14:53they're in a series of cards that says
- 14:56do this then do this then do this you
- 14:58see so we have a sequence of card with
- 15:01instructions on them he doesn't even
- 15:03have to remember the instructions he's
- 15:06rather stupid the first filing cloture
- 15:10could say go get the card that
- 15:13instruction meant go into room five
- 15:17opened the drawer push your fingers
- 15:20through the card lift and so forth okay
- 15:22so if you want to get the card to read
- 15:25it and then carry it back and write it
- 15:27down you could have a list of
- 15:29instructions for this idiot instead of
- 15:31saying get the card you say look in
- 15:33these set of instructions please first
- 15:35instruction walk over to the file second
- 15:37rope pull out the drawer but if at home
- 15:39so does it done and so forth so all he
- 15:41has to do is keep track of which
- 15:43instruction comes after which he's
- 15:46really quite stupid but man is he fast
- 15:49dumber but faster okay the key of it all
- 15:53is dumber but faster right and so what
- 15:57we're having is the filing systems with
- 15:59ever-increasing speed of the file clerk
- 16:03but ever stupider file clerks okay and
- 16:07they're getting better assistant Chris
- 16:09brevis file everything now the last
- 16:12fellow that we've got in this not the
- 16:15last one but the willit next to the last
- 16:17one is unable to remember which
- 16:21instructions on
- 16:23well what's the next instruction oh but
- 16:27he can add one he knows how to change
- 16:29something with one he has a little
- 16:30counter but he pushes a button and it
- 16:32goes up one okay so all he has to
- 16:36remember is the following push the
- 16:41button on theirs a little register that
- 16:43he can read okay that's a push that we
- 16:46call it the program counter or
- 16:48instruction count all right push the
- 16:50button that changes the instruction
- 16:52count by one that's the only button he
- 16:53knows how to push that okay that's the
- 16:55first thing spike read the number there
- 16:58on the program counter and take that
- 17:01card out that instruction number out
- 17:03okay and that says go get this paper or
- 17:06transfer this so whatever it is you see
- 17:10because we have already put all the
- 17:12instructions in a certain order and then
- 17:14put the card back you're finished do the
- 17:16intern take out read the instruction and
- 17:18through the instruction and put the card
- 17:20back okay then the next cycle he has
- 17:23push the button on the program counter
- 17:25read the program counter it's the next
- 17:28number you know anybody couldn't
- 17:30remember so he has it there it's the
- 17:31next card takes the next corner and it
- 17:34tells him what to do next and so on okay
- 17:36so he doesn't even have to remember
- 17:38where he's at
- 17:40as long as he's got this one little
- 17:41gadget inside which I've beginning to
- 17:44think you could see could be done
- 17:45mechanically that is we can make a
- 17:48device that all you push a button and
- 17:49number changes by one right
- 17:52in fact so that that almost got it but
- 17:58we find out very much fast at ten times
- 18:00faster than this marvel who was so
- 18:03stupid but so fantastically fast which
- 18:06ten times faster than this fellow but he
- 18:09can't read letters he doesn't know what
- 18:12they mean doesn't know what the numbers
- 18:14mean okay so how is he gonna what can he
- 18:17do if he can't read anything he can't do
- 18:19anything I grant you that I grant you
- 18:21that but he can distinguish two signs
- 18:25one from the other which we'll call high
- 18:27and low or black and white or one and
- 18:31zero or mark and Norma whatever all
- 18:34right just he only can read
- 18:36not any kind of letter but just one
- 18:37little spot it's yes let's say we always
- 18:40make it red and blue you see is it red
- 18:42or is it blue so we make a lot of spots
- 18:44for him red blue spots it's all he can
- 18:46read what I need to eat how can we make
- 18:47him do anything how can he know what an
- 18:50a is suppose we got letters we want to
- 18:52write the letters for names or something
- 18:54like that so we would like to instruct
- 18:57him in the letters for the names to see
- 19:00so instead of saying we tell him which
- 19:03Oh first better to give a better example
- 19:05by this time because they have to use so
- 19:07many cards in so many files the files
- 19:09have gotten larger right there are lots
- 19:11of filing cabinets in many rooms all
- 19:14over and we this poor fool has to be
- 19:17able to find the right cabinet now
- 19:19previously we labeled all the cabinets
- 19:21with the names of the sections from from
- 19:23small stoop to zoology and so forth here
- 19:27and this is in box 34 and this is all
- 19:31over it's like that places in Esalen
- 19:32have numbers on them and so forth I'll
- 19:34show you how we could do that without
- 19:35having only with red and blue dots on
- 19:38the on the rooms for those particular
- 19:41kind of workshop people who cannot read
- 19:44numbers all right I will still be able
- 19:47to do it I'm not sure how we'll do it
- 19:49let's do it with the esselman rooms it
- 19:50just makes it more interesting I don't
- 19:52propose this as a practical device but
- 19:54perhaps it is and it goes as follows
- 19:56just till you take the map and you
- 19:59divide the rooms through the middle and
- 20:01say these are the red first level red
- 20:04and blue rooms okay then you take the
- 20:10red rooms and divide them in half let's
- 20:12say those are the higher part of the
- 20:13hill in the lower part and say they are
- 20:15secondary red or blue and the blue ones
- 20:18the main blue ones have been divided at
- 20:21the primary and secondary rooms like
- 20:23this no I see that I don't have red and
- 20:26blue so I'll use brown and orange it's
- 20:28perfectly all right had I said brown and
- 20:30orange it would be more like they
- 20:31understand that we couldn't be any two
- 20:34colors okay so and let's first draw
- 20:40what in yellow a lot of rooms can't see
- 20:47the rooms okay I don't have enough thing
- 20:51so these are the rooms will be all right
- 20:55let's say we had this many rooms I've
- 20:59got them all laid out in a straight line
- 21:00but it doesn't make any difference where
- 21:02they are on the map right we got eight
- 21:05rooms I know you got more rooms than
- 21:07eight rooms but just see the scheme will
- 21:09work just as well for any number of
- 21:11rooms so what we're gonna do is we're
- 21:13gonna mark all these rooms with a black
- 21:15dot as a first dot I mean a brown one
- 21:19all right and these will get orange dots
- 21:23okay
- 21:27now of the brown dotted rooms we think
- 21:31of the brown dotted rooms and we look at
- 21:32the next dot which says the first half
- 21:35of them get brown on that dot and the
- 21:39second half of those get orange all
- 21:43right and then the first half of these
- 21:45get brown and the second half gets
- 21:49orange I say but still you're filled
- 21:53okay now you look at the brown brown
- 21:55rooms so any pet is a brown brown the
- 21:58brown orange rooms
- 21:59the orange brown rooms and the black
- 22:01orange orange rooms of the brown brown
- 22:03rooms we label the side ones Brown as
- 22:06the first each pair gets the front end
- 22:09brown and the other one gets orange and
- 22:11lo and behold we got eight rooms and
- 22:15with three little dots each of which can
- 22:18only have one of two colors we can
- 22:20identify the room so the guy who has to
- 22:24locate himself and you can't read
- 22:26numbers but can read whether a dot is
- 22:28brown or orange will in this system be
- 22:30very easy to find his unique room in
- 22:33fact it's easy to find the room which is
- 22:35different of course as you already know
- 22:37the numbers on these rooms around here
- 22:39do not locate the rooms right but this
- 22:42new system really in locate the room the
- 22:45first Brown tells us to kind of go over
- 22:47here somewhere
- 22:48the next round swap more is it orange
- 22:50take that side
- 22:53so if the filing cabinet can happen this
- 22:56can be very large and have labels on him
- 22:59which I like these brown dots and orange
- 23:01dots but because instead of being eight
- 23:03there are say a thousand such rooms the
- 23:06read turns out you only need ten dots to
- 23:08do it a million such rooms is only
- 23:10twenty dots because there's so many
- 23:12different combinations of brown brown
- 23:14brown orange brown I'm bombed around by
- 23:16men for twenty long so many ways in a
- 23:20million different ways so you have that
- 23:23way you can label a large number of
- 23:24different cabinets and have a file clerk
- 23:27which you can only read that's one of
- 23:29two alternatives and make sense of it
- 23:31and so we can do it with rooms and also
- 23:35with the letters of the alphabet because
- 23:37we take the letters of the alphabet and
- 23:38write them along and label them the
- 23:42Bradford the letters on this side of the
- 23:44alphabet of the brown letters first
- 23:46primary brown and the others are orange
- 23:48and never those you make the brown so
- 23:49these could have been ABCDEF yo so he
- 23:52could teach him a different way to write
- 23:54his alphabet
- 23:55he's so dopey he could only read these
- 23:57but we smart enough to convert it so he
- 24:00can be therefore using names and numbers
- 24:02but they're written in a different code
- 24:04it's like the dot-dash system of Morse
- 24:06only slightly more organized
- 24:09we call it ones and zeros brown and
- 24:12orange I'd call again whatever you can
- 24:14only read two possible things okay so
- 24:17this the new file clerk can only make
- 24:20out one of two alternatives in any
- 24:22particular spot of course he has to
- 24:24realize is do first the first one and
- 24:26then he's up to the second when he saw
- 24:27him first makes one choice and then the
- 24:29next choice and next choice and
- 24:30according with with this and then
- 24:32determines the letter of the alphabet if
- 24:34he had to talk to us and make an output
- 24:36he's not going to be able to just put
- 24:39this ones and zeros we're not going to
- 24:40be able to read it
- 24:41so suppose he wants to say something and
- 24:43he wants to put an out but you ask him
- 24:45for the name of the the best-selling the
- 24:48guy who sold the most in California and
- 24:53he he does it with his dots and I'll
- 24:54tell you a little more about how you can
- 24:55do that and comes out that his name
- 24:58starts with an AE say or let's say
- 25:01starts with a C whereas a C for him it's
- 25:05a three dot
- 25:05Sanna - right but he wants to print see
- 25:08for you what can you do we wanted to see
- 25:10it look like a scene so what we have
- 25:14done for him is we imagine he's going to
- 25:17write this on some kind of a screen that
- 25:19we have divided into squares okay like
- 25:24this I should make more and we tell him
- 25:31whether to mark the square or not in the
- 25:34electronic device with a pulse so it
- 25:37lights up on the screen or not by
- 25:39whether it's a brown or a orange dot
- 25:41there so he put a brown dot here well
- 25:44let me first draw the C or C is going to
- 25:46look like this is where the orange dots
- 25:47go okay there's the C all right not a
- 25:55very good see but to see if you add more
- 25:57dots and a finer screen it would make a
- 25:59much better see so so we put all these
- 26:02Browns and so on and then we put into a
- 26:04filing cabinet under the labeling for
- 26:08the third letter of the alphabet this
- 26:10pattern so when it cuz his when he's not
- 26:13working internally which is you can use
- 26:15this other system but wants to
- 26:17communicate with us we told him how to
- 26:19do it what we get for a seat by putting
- 26:22in the filing of that that he's supposed
- 26:24to put out on the screen so when he's
- 26:27finished looking at that we look at the
- 26:28little white dots and black areas we see
- 26:31a shape of a seat so the hardest thing
- 26:35he has is communicating with us getting
- 26:37the information converting at the dot
- 26:39and getting the dots back to the form
- 26:41that we've we're used to the same thing
- 26:44can be done with numbers of course
- 26:45suppose that he had only deal with
- 26:47numbers from one to a thousand and
- 26:49twenty zero to a thousand and 23 it's a
- 26:52happy case where you can divide ten
- 26:55times you can divide those in half you
- 26:57say Oh numbers described by the same
- 26:59bunch of dots by taking a you know the
- 27:02top half of the numbers or the bottom
- 27:05half of the numbers I already did it
- 27:06with numbers
- 27:07it was the numbers on the rooms so we
- 27:09can use these dots and so forth to
- 27:12represent numbers the same way
- 27:16and now we can use in a particularly
- 27:19insane I mean stupid a file clerk
- 27:23perfect and it's only useful of course
- 27:24if he's really very fast because
- 27:26everything requires him to looking and
- 27:28his damn files all the time because he
- 27:30knows so little and that's what
- 27:32ultimately has been developed first of
- 27:35all in order to get up speed instead of
- 27:37having to get up and walk over to the
- 27:39file we put the files not on cars but on
- 27:43little tape decks huh little tape decks
- 27:47electrical and we send the signal turn
- 27:49on the tape they can listen to the
- 27:51signal that comes out we don't have to
- 27:53run over there we've got a telephone so
- 27:54to speak you we tell which one to go off
- 27:56then it sends back what's on that tape
- 28:00so you see that we can file things not
- 28:02on pencil and paper but there the
- 28:04electrical signals or magnetic different
- 28:09kinds of techniques they're off of
- 28:10electrically saving information and it
- 28:13turns out you can do that smaller and
- 28:15smaller until the filing cabinet is the
- 28:17speak which contains millions of items
- 28:21and what happened what you're doing is
- 28:23you're signaling to the different filing
- 28:25cabinets depending upon the ones and
- 28:27zeros there are switches inside that
- 28:29tells which one it goes to and the
- 28:31information comes in and out
- 28:32electrically that's much faster than
- 28:34carrying cards around and running around
- 28:35in sneakers and so that's the way that's
- 28:38done and by the time we got a file clerk
- 28:40this stupid we can do it mechanically we
- 28:45can tell whether two dots are the same
- 28:46for instance we can ask him when the two
- 28:48looked the same do this so if there's
- 28:50two brown ones or two orange ones do
- 28:52this now it's rather easy to make
- 28:55mechanical devices which will do things
- 28:57like that for example instead of brown
- 29:02and orange dots you could have
- 29:03electrical voltages which are either up
- 29:06or down
- 29:07you know there's current dah no there
- 29:08isn't so instead of a dot of different
- 29:11colors we just have a voltage or no
- 29:13voltage on a particular wire at a given
- 29:15moment or if you would like but this
- 29:18isn't the way it's the electrical one is
- 29:19the way it's done but if you would
- 29:20prefer you can imagine you made a
- 29:22hydraulic computer with pipes with
- 29:24pressure with water going through and if
- 29:27you look at the pipe and water squirt
- 29:29that's a black dot and the waters no
- 29:31water there that's the other kind so
- 29:33it's about that easy so you'd make the
- 29:34pipes go squirt squirt not squirt squirt
- 29:37squirt not squirt that's that this one
- 29:39is this room right now what we need is a
- 29:42situation to compare things that only
- 29:44squirts of two things let's suppose we
- 29:47were looking for both dots be brown only
- 29:50then should you make a brown dot in
- 29:52other words two pipes such that if both
- 29:54pipes have water in them then only then
- 29:58should water come out the other one what
- 30:00we need only a valve a valve operated by
- 30:03water we have a pipe like this with a
- 30:07valve which is a thing you don't turn it
- 30:10on let the water through the waters
- 30:11trying to go through here it's turned
- 30:12off by a faucet which only takes a small
- 30:15turn and has sticking out above it
- 30:17instead of an ordinary handle a flat
- 30:20vane okay that we're going to scrape
- 30:22with water and that's going to push the
- 30:25vane around and open the valve so here's
- 30:27the for the things coming in with the
- 30:29water to operate that so when the water
- 30:32goes here it turns the water on there
- 30:33now if I put two such the bowels in
- 30:36succession in the pipe okay
- 30:39and I had the water coming in need two
- 30:42different pipes then it was only work
- 30:45that is water will only come out of here
- 30:46if both of these pipes are squirting
- 30:48because if I got only one pipe squirting
- 30:51in the other not this valve was off but
- 30:52this on so water don't get through on a
- 30:54counter that's in the way
- 30:55and vice-versa okay so this is what you
- 30:58call an and you get result here when
- 31:02both this and that are on then you get
- 31:04that on you could do an or just as well
- 31:08when you get a result if either one is
- 31:10on but that's different kind of a logic
- 31:14and the way to do that is simple enough
- 31:16just arrange the pipes so that the water
- 31:21that's coming in is split into two
- 31:25possible pipes let me see how I draw
- 31:27this yes well the brown and the orange
- 31:29is just an accident of fate of having
- 31:32put the orange cap on the brown
- 31:36gadget that some would straighten that
- 31:38out right now and here we go the pipes
- 31:42go like this the input is here but we go
- 31:46with the two valves this way here's the
- 31:47one with the other valve okay and the
- 31:50two squares let's say this one squirts
- 31:52here and this one squirts here you got
- 31:54to get some geometry as three-dimension
- 31:56got to get this pipe on top of this pipe
- 31:57wouldn't be trouble anyway the idea is
- 32:00that these then come together and you
- 32:03might ask under what circumstances does
- 32:05water come out of there well clearly if
- 32:07either this is open or that's open to
- 32:09either goes around this way or it goes
- 32:11around this way or both that's an or you
- 32:14get choked out only when one or the
- 32:16other or both is on and so we could say
- 32:18very simple comparisons of these black
- 32:21these dots or Bennet ones and zeroes or
- 32:25fresh it water and no water or
- 32:28electricity and no electricity
- 32:29voltage or no voltage electrons or no
- 32:32electron and so we can make the device
- 32:35simple enough now that we don't need a
- 32:38human being anymore
- 32:39to do the file work and the whole system
- 32:43is now a computer it's all done
- 32:45electrically and it has this kind of
- 32:48switches in it valves are electrical
- 32:51valves are called transistors and how
- 32:53they work in detail of how the electrons
- 32:56come in here affect the electrons going
- 32:57there I won't describe but they're just
- 33:00granting that a transistors are like is
- 33:02the analog of a vowel but for electric
- 33:04current then you're going to understand
- 33:06that large numbers of transistors lots
- 33:08of these vowels making comparisons
- 33:10switching where the current goes to find
- 33:12the right filing place in the Box where
- 33:15all the stuff is filed and so forth
- 33:16would constitute a computer and that all
- 33:19computer does is what a filing cabinet
- 33:21system can do it can do everything that
- 33:26an ordinary most things that an ordinary
- 33:28file clerk system can do it can multiply
- 33:32numbers because it's got we store the
- 33:34numbers we store the combinations they
- 33:36can add it can do all these things even
- 33:37though it for hardly do anything
- 33:41and you might ask is there some kind of
- 33:43designer computers that can do more than
- 33:45other kinds of computers and the answer
- 33:47is no it turns out once you begin to
- 33:49understand this that if you try to add
- 33:51more complicated things you can always
- 33:52put them back in filing systems and use
- 33:56the same system to do a more elaborate
- 33:57thing so all the computers can do the
- 34:00same things but maybe they take longer
- 34:02or so it may be a matter of efficiency
- 34:04but they can all do the same things
- 34:06they're all Universal inside if they're
- 34:09big enough their limitations are how big
- 34:10is your filing system maybe there's not
- 34:13enough room for all the cards you want
- 34:14to put in and things like that but
- 34:16that's the only the only differences
- 34:18between the between the different
- 34:20machines and any rate that is supposed
- 34:23to be an expose of what the heck's
- 34:25inside the machine now let's ask what
- 34:28the miss such a machine could do first
- 34:32of all the same machine can be used for
- 34:35more than one problem by just having
- 34:37different instructions list some
- 34:39instruction what to do do this then that
- 34:40to do that to deep deep deep deep and
- 34:42another problem you do something
- 34:43entirely different this might have been
- 34:46a business with salesmen and so on and
- 34:48now you want to do oral company reports
- 34:52and listings of what they discover when
- 34:54they drill all right so all new numbers
- 34:57or all new instructions of how to handle
- 34:58a numbers everything what do you do by
- 35:02another filing system it's more
- 35:04expensive to do that than to do the
- 35:06following
- 35:08throw away all the cards from the
- 35:10business company
- 35:11wait a minute suppose you want to come
- 35:12back in all right take everything that's
- 35:14on the cards of the business company and
- 35:16make photocopies and store them in the
- 35:18basement now erase all the cards so if
- 35:20you want to come back we'll come back
- 35:21then you go down the basement from the
- 35:23time year last year when you were doing
- 35:25the oil company problem and pick up from
- 35:29the photocopies all this stuff that was
- 35:31supposed to be on the cards for oil
- 35:33business and then just fill out fill up
- 35:36all the cards with the oil companies job
- 35:39with the instructions for oil companies
- 35:41and our dumb file clerk is now an oil
- 35:43company file system okay because he's
- 35:47got new instructions and
- 35:50these things that in the basement the
- 35:52analogy that I had wanna make is those
- 35:54things are dead not operating and I just
- 35:57stored they're not easy to get at it's
- 36:00hard to get down to the basement it
- 36:01takes a long time to pill pull them up
- 36:03and set them in all those cards but you
- 36:06do that just once in a while when you
- 36:08want to change your problem when you've
- 36:10got them all in then you can rapidly
- 36:11take them and put them in compare them
- 36:13and do this and do this let the filing
- 36:14cop click is supposed to do so we have
- 36:18cassette tapes or hard disks of floppy
- 36:22disks or various and sundry different
- 36:25ways of taking a large numbers of
- 36:27instructions out and sticking them on
- 36:30the disk and leaving them there putting
- 36:32them in your back pocket throwing them
- 36:33around in the boxes while the computer
- 36:35is doing something else then if you want
- 36:37to change a computer to a word processor
- 36:38instead of a a game or whatever it is
- 36:41then you just take out one this put the
- 36:44other disk kid puts new stuff into the
- 36:47computer all new instructions done file
- 36:50clerk working like a son-of-a-bitch and
- 36:53a big memory outside and that's why
- 36:56computers could do so many things
- 36:58apparently the same computer it doesn't
- 37:01do so many things it always does the
- 37:02same thing it follows instructions and
- 37:04the instructions are very done and it is
- 37:07low-level ok that's the end of the
- 37:14expose but they would like to make some
- 37:16remarks and some things about because
- 37:19people like to think of things more than
- 37:21just how does it work they would like to
- 37:23know what's the future why can't we
- 37:26improve this looks what we've got now we
- 37:29have this enormous memory with lots of
- 37:31data all around which is sort of sitting
- 37:33there and this one little section where
- 37:35something's happening which I call the
- 37:37file click before which is the systems
- 37:39which go and get something pull it in
- 37:41here and do something over you better
- 37:43put it there and it takes something else
- 37:44and put it here and put it there put it
- 37:46there and what a great so this poor fire
- 37:48clerk is working perpetually with a
- 37:49tremendous rate of speed going
- 37:52practically crazy and he does in fact I
- 37:54just estimated something like 10 million
- 37:56times faster than an ordinary file click
- 37:58that's 10 times faster seven times if
- 38:02you know what I mean
- 38:02ten tons ten tons but it spam fast and
- 38:09that's the electrical things of that
- 38:11fast and but he's working very hard but
- 38:17the rest of the system which is the
- 38:19memory and you've heard they made now
- 38:20memories with 256 K bytes K just means a
- 38:23thousand and twenty four so they mean
- 38:25256 times 1,024 eight dot were symbols
- 38:31in one tiny chip okay it's a lot and you
- 38:34put several chips and you got a terrific
- 38:36computer except for the guy the file
- 38:39click which is called the central
- 38:40processor who has to look at this this
- 38:44program can't do in check and change it
- 38:45and look at the next instruction and
- 38:47going going alright and he's working
- 38:49very hard so an obvious way to improve
- 38:51the thing is to get another file clerk
- 38:54why not have an army of file clerks
- 38:57turns out at first that it looked
- 38:59extremely difficult to do that because
- 39:01there's all kinds of technical difficult
- 39:04problems suppose that he one guy has
- 39:06taken a number out and he's getting
- 39:08ready to change it he's gonna do
- 39:10something and then change the number the
- 39:11man just sold something he wants to
- 39:12change his he and then put it back and
- 39:15while he's doing that the other file
- 39:17clerk is taking the card he doesn't know
- 39:19whether it's before or after the first
- 39:21file clerk has changed the number and
- 39:22it's very important to know that because
- 39:24he's going to use that number there so
- 39:26that's to be a certain amount of
- 39:27organization among the file clerk and
- 39:29don't forget that kind of dumb so the
- 39:31organization must also be fairly done
- 39:33and has turned out for many years it was
- 39:36a belief that it was difficult or almost
- 39:40impossible to easily arrange a system
- 39:42with many file clerks they were always
- 39:44turned out to be easier to make one file
- 39:46clerk worked very hard that the made
- 39:48several working because of all the what
- 39:50you might call bugs and difficulties
- 39:52that come from them all using the same
- 39:53information and changing it on each
- 39:56other and so on and organizing that the
- 40:00part of laying out the instructions is
- 40:02called a programming and a programmer
- 40:06works out how to put what instructions
- 40:08to write
- 40:10the machinery the wires memory in the
- 40:14boxes where to put the cards but it's
- 40:15not an analogy and the little processor
- 40:17in the middle with little switches it's
- 40:19called the hardware so it always turned
- 40:24out that with a little more clever
- 40:26software which means cleverer programs
- 40:29this single file clerk could do what the
- 40:33others would do because the others were
- 40:34confounded by the problem of
- 40:35interference but recently it's been
- 40:39shown that it's a misunderstanding and
- 40:43with clever new ways of analyzing the
- 40:46thing we have now figured out how to
- 40:49make things run with numbers of file
- 40:51clerks there's two different general
- 40:56system there's one system which has
- 40:58something you know a reasonable number
- 40:59like 64 128 file clerks all working on
- 41:03it saying similar they work on almost
- 41:05separate parts of the memory that's the
- 41:07way it's organized and only to once in a
- 41:09while exchange information so they're
- 41:11not doing anything to each other's cards
- 41:14they're each working in separate
- 41:15sections and there's also a machine
- 41:18called a connection machine which has
- 41:2064,000 processors in it which is a sort
- 41:24of a leap into the blue wild blue yonder
- 41:26at a time when they were trying to do
- 41:27with two processes and if the 64
- 41:30thousand process that could all be made
- 41:31to work at the same time it'll be 64
- 41:34thousand times faster than it was before
- 41:36just like that because they're all
- 41:38working together the only problem is to
- 41:41organize the problem and the program so
- 41:44that you can do the job in a way that
- 41:46does use 64,000 guys at the same time it
- 41:50turns out that's not as hard as it
- 41:51looked at first and that's a thing for
- 41:53the future I'm talking about the future
- 41:55they're building such a machine and
- 41:56they're learning how to program it that
- 41:59is how to arrange the 64,000 processes
- 42:01which by the way are each in fact
- 42:04somewhat stupider than the program is
- 42:07that I was talking about before because
- 42:09they can't even read the code for their
- 42:11instructions but I mean they know as
- 42:14instructions read what's in that file
- 42:17place that means go over switch this
- 42:20switch that take you go over get the
- 42:21file open the drawer closes
- 42:23for they have they can't even read that
- 42:26so that they have to be instructed on
- 42:28the goal and so there's another machine
- 42:31on the outside that instructs some more
- 42:32what to do but it has to tell them all
- 42:34because see they all have to do the same
- 42:36thing at the same time because the
- 42:39instructions go to everybody do this and
- 42:41they all do it but if they all do it
- 42:44you're going to be in a great difficulty
- 42:45if they all do exactly the same thing
- 42:47and the only opportunity they have the
- 42:48only thing you two can do that's
- 42:49different is that you can instruct or
- 42:52they can keep a little memory thing that
- 42:54says don't pay attention to this
- 42:55instruction in other words you can get
- 42:57some to do something and the others to
- 42:59do nothing then next time you wanted
- 43:01them to do something if you wanted one
- 43:03to do one thing and want to do another
- 43:04you have to do it in two steps
- 43:05do this you stay put through this you
- 43:09stay bored and so on okay and so on so
- 43:13it's rather interesting because in
- 43:15trying to manage the sixty-four thousand
- 43:17they all have to be much simpler and all
- 43:19the time it gets simpler it gets sort of
- 43:20slower but the question is whether we
- 43:22gain from the sixty-four thousand what
- 43:24we lose from the slowness and it depends
- 43:26we learn by experience that's the future
- 43:29finally I would like to just say
- 43:31somewhere it's about what the computers
- 43:34can do and you'll see they can do only
- 43:37what you would be expected to be able to
- 43:39do with a filing system and a reasonable
- 43:41file clerk I'll explain an example of a
- 43:44unreasonably good file clerk later
- 43:46that's better than one that we can make
- 43:47with machinery ok so far we seem to be
- 43:50able to imitate any file clerk real far
- 43:53click with machinery but I'll mention a
- 43:55few cases that we don't know how to do
- 43:57that what we need to do of course is to
- 44:02get a definite procedure to convert what
- 44:06you want the clerk to do into an
- 44:07absolutely definite procedure we every
- 44:10step is precisely defined in this stupid
- 44:12way exactly and if you can do that then
- 44:17you can get the system to work now will
- 44:20the system think if you could define
- 44:24exactly a definite procedure tell
- 44:26somebody exactly how to think which by
- 44:28the way is what the members of my
- 44:30workshop have expected me to do for them
- 44:33to tell him exactly step-by-step what to
- 44:36do to think if I could do that I could
- 44:39do it for a computer and I wouldn't have
- 44:41you know they could get the computer the
- 44:42thing but nobody knows what we do or how
- 44:45to define exempt which correspond to
- 44:48something abstract like thinking but
- 44:51nevertheless we could make the machines
- 44:53which play chess which was supposed to
- 44:54be something that takes thinking and
- 44:56what exactly do they do what definite
- 44:59procedure can you make with a big file
- 45:02system very fast operating gadget by
- 45:05which the thing could be used to play
- 45:07chess
- 45:07never mind the input and output the
- 45:10information of where their pieces on the
- 45:11chessboard are converted into numbers or
- 45:13black dots and so forth ones and zeroes
- 45:17they're called inside the machine and
- 45:20then it proceeds so never mind a
- 45:21translation the idea is in a given
- 45:24position which is a whole lot of
- 45:25information that's where it is
- 45:27you want to know which way to move so
- 45:29you say well there are many ways I could
- 45:30move you look at the rules for how to
- 45:32move the night goes this way to bring
- 45:34you this way so on and you just list all
- 45:36the different ways it could move and you
- 45:40see all the new gap possible positions
- 45:42then you say in each one of those which
- 45:44way could the other guy move they're
- 45:46getting pretty big isn't it
- 45:47but there are big machines and they've
- 45:49got lots of storage space so there's how
- 45:51does it what's the next room and if he
- 45:53does that what can I do and you just
- 45:55check every one of the positions after
- 45:57let's say four or five or six half moves
- 46:00these are called happen with one side
- 46:02moves to the other side move and see
- 46:04which of the final positions
- 46:06you're a better off and better off might
- 46:09be some little rule like you haven't
- 46:10been in check I mean haven't had your
- 46:12King lost that means you're not dead and
- 46:14you've got more pieces than the other
- 46:16guy okay so you look down six steps down
- 46:20to see which move is the best to make
- 46:23where you got the best possible outcome
- 46:25and you make that move then your
- 46:28opponent makes a move then you start
- 46:30again this time going down six again of
- 46:32course you're going deeper now because
- 46:34the game is preceded a little bit
- 46:35further and that's all there is to it
- 46:37what the machines do is just a
- 46:39tremendous amount of trying different
- 46:41positions human being doesn't the human
- 46:44being tries about 35
- 46:45the sponsor he can tell when he's in a
- 46:47position he tries about 35 looks at
- 46:50different moves before he makes a
- 46:52decision whether the machine makes
- 46:54something like 35 million positions to
- 46:57check that doesn't make the Machine
- 46:59better than the other guy we don't
- 47:00understand how we do it we cannot give a
- 47:02direct procedure for this the man does
- 47:05it by recognizing a pattern oh this
- 47:08night can can this night can fork the
- 47:11the king and queen of somethings if it
- 47:13goes here so I have to watch out about
- 47:14that square he sees patterns at least it
- 47:17describes it that way we really don't
- 47:18know how it work and this business of
- 47:21the describing patterns and so forth is
- 47:23something that we haven't been able to
- 47:25put into a precise form when he says it
- 47:27looks oh I just see that it's a good
- 47:28idea to try this and I tried it we don't
- 47:30know how he does that so we can't make
- 47:32it play like a human plays but we can
- 47:35make it play better than almost all in
- 47:37human machines computing machines have
- 47:42been used for instance for designing
- 47:44machinery or designing something in
- 47:46particular designing a computing machine
- 47:48for instance or something like that
- 47:50in a computing machine yet that the
- 47:52different elements the memory and so on
- 47:54and different locations with wires in
- 47:56such a way that the wide the wire
- 47:58lengths are shortest so that the time is
- 48:00quickest and the paths that are being
- 48:02used most on closest to where you want
- 48:04to use them and things like that and so
- 48:07you try to figure where should you lay
- 48:08them out on this chip of silicon and
- 48:11there has been quite a problem of design
- 48:14we have engineers that worked very hard
- 48:15at designing these things and working
- 48:17these things out in all we do in the
- 48:20computer now is to try it - try large
- 48:24numbers of possible arrangements we just
- 48:29give it an instruction put it here put
- 48:30this here then this this this this and
- 48:32how much why do you need now put here
- 48:34here here here here over there and then
- 48:37pick the one out which has the biggest
- 48:38more ones the biggest of the lowest the
- 48:44best quality whatever it is you do to
- 48:46measure how good this particular design
- 48:48is like the amount of time
- 48:51that it takes to do a calculation or how
- 48:54much silicon you use or something like
- 48:55that so we can select from a very large
- 48:58numbers of alternatives the best
- 49:00alternative
- 49:01what narrowly a person doing that
- 49:03doesn't waste his time with obviously
- 49:05useless alternatives but we do not know
- 49:08how to put - well that idea of the
- 49:11obviously useless if we try to make to
- 49:14shop the rule that it's useless we miss
- 49:16sometimes a good opportunity that would
- 49:18have been a good thing so that that's as
- 49:20far as we can go with that you've
- 49:22probably heard that machines have been
- 49:24used to the dock to be almost like
- 49:28doctors expert systems which can
- 49:30diagnose disease now how can a damn file
- 49:32clerk why it's easy isn't it how would
- 49:35you diagnose disease you write down all
- 49:37the symptoms and then you'd like to have
- 49:40a book that you could look up that says
- 49:41here's all the symptoms and this is what
- 49:43you go and in a complicated cases you
- 49:46list all the symptoms and in there it
- 49:48says it's either cholera morbus of the
- 49:50Borba sore its back there a see Miele
- 49:53whatever it is you see however you can
- 49:55tell the difference by looking with
- 49:57ultraviolet like up the nostril like but
- 50:00what nobody I don't bother to look with
- 50:02ultraviolet light off at the nostril so
- 50:04you don't know the answer to that so the
- 50:06thing comes back and says look with
- 50:07ultraviolet on the nostril and tell me
- 50:09whether it gets through or not say yes
- 50:11okay it's back to see me so this filing
- 50:15system contains all this stuff plus the
- 50:17incomplete decisions that require more
- 50:19information and once it's been arranged
- 50:22so that when it comes to a place it's
- 50:23incomplete it simply sends back and says
- 50:25make the following test and tell me the
- 50:27result their thing doesn't work as well
- 50:30as a real doctor but anyway you get some
- 50:34idea of how machines can be doctors how
- 50:37machines can be chess players and our
- 50:39machines can be designers of equipment
- 50:42or layouts for businesses or whatever
- 50:44routing for trucks and so on but just
- 50:47trying what kinds of rulings in seeing
- 50:49which is the best that's all there is to
- 50:51it
- 50:52it's a filing system and anything that
- 50:55you can put in a filing system and think
- 50:57of how a big filing system could do it
- 51:00especially things that you just have to
- 51:02remember a lot of stuff or try out a lot
- 51:04of possibilities
- 51:05those things can be done with a machine
- 51:07it's fun to compare everybody wants to
- 51:11install ticularly well I'll let that be
- 51:12in the questions to compare no doubt
- 51:15somebody will ask me how about this and
- 51:17that so I'm done okay well I'll answer
- 51:24question what time is it I used to hope
- 51:27I'm fine okay I got time for questions
- 51:33yes sir and different languages but if
- 52:27you take my view that is just a
- 52:30glorified high class very fast but
- 52:32stupid filing system then you can
- 52:34understand the universality it's just as
- 52:36universal as a set of boxes and drawers
- 52:39and cards and so forth with a clerk it
- 52:42could knows how to write the numbers and
- 52:44the things down in it she can use or he
- 52:46it's always a pain he can
- 52:53it can do one kind of a job or another
- 52:56kind of a job depending on what's
- 52:58written on the cards and what kind of
- 52:59instructions are given to the clerk and
- 53:01that type of universality is precisely
- 53:03the universality you're talking about
- 53:05that's what the universality of the
- 53:06computer the computing machine is an
- 53:09automatic filing system with regard to
- 53:25that questions first of all they think
- 53:27like human beings I would say no and
- 53:29I'll explain in a minute why I say no
- 53:31and second that they be more intelligent
- 53:33in human beings is the question
- 53:36intelligences to be defined if you were
- 53:38to ask me I have a better chess players
- 53:40then any human being possibly can be yes
- 53:43I get you someday and they best better
- 53:46chess players than most human beings
- 53:47right now one of the things by the way
- 53:50that we always do is we want the dawn
- 53:52machine to be better than any body not
- 53:54just better than us if we find a machine
- 53:56it can play chess better than us it
- 53:57doesn't impress us much we keep saying
- 53:59and what happens when it comes up
- 54:01against the Masters we imagine that we
- 54:03human beings are equivalent to the
- 54:05Masters and everything right the machine
- 54:07has to be better than a person in
- 54:09everything that the best person does at
- 54:13the best level okay but it's hard on the
- 54:15machine but with regard to the question
- 54:17of whether to make it to think like a
- 54:19machine my opinion is based on the
- 54:21following idea that we try to make these
- 54:24things to work as efficiently as we can
- 54:26with the materials that we have the
- 54:28materials are different than nerves and
- 54:30so on if we would like to make something
- 54:34that runs rapidly over the ground then
- 54:37we could watch a cheetah running we
- 54:40could try to make a machine that runs
- 54:41like a cheetah but it's easier to make a
- 54:44machine with wheels with fast wheels or
- 54:46something that flies just above the
- 54:48ground in the air when we make a bird
- 54:51the airplanes don't fly like a bird they
- 54:54fly but they don't fly like a bird okay
- 54:56so they don't flap the wings exactly
- 54:59they have in front another guy of a
- 55:01gadget that goes around or the more
- 55:03modern airplane has a tube that you heat
- 55:06this the air
- 55:06squirted out the back a jet propulsion a
- 55:10jet engine as internal rotating fans and
- 55:15so on and it uses gasoline it's
- 55:16different right so there's no question
- 55:19that the later machines are not going to
- 55:21think like people think in that sense
- 55:25with regard to intelligence I think it's
- 55:29exactly the same way for example they're
- 55:31not going to do arithmetic the same way
- 55:33as we do arithmetic but they'll do it
- 55:34better let's take bath ematic very
- 55:36elementary mathematics arithmetic they
- 55:39do arithmetic better than anybody much
- 55:41faster and differently but it's
- 55:45fundamentally the same because in the
- 55:47end the numbers are equivalent right so
- 55:49that's a good example of we're never
- 55:50going to change how they do arithmetic
- 55:51to make it more like humans that would
- 55:53be going backwards because the
- 55:56arithmetic done by humans is slow
- 55:58cumbersome and confused and full of
- 56:00errors where these guys are fast if one
- 56:04compares what computers can do to the
- 56:06human beings we find the following
- 56:09rather interesting comparisons the first
- 56:11of all if I give the human being a
- 56:14problem like this I'm going to ask you
- 56:17for these numbers back every other one
- 56:20in reverse order please right now a
- 56:24greater series of numbers and I want
- 56:25them to you didn't give me what to me
- 56:26back in reverse order every other one
- 56:29I'll tell you I'll make it easy for you
- 56:31just give me the numbers back the way I
- 56:32gave them to you they're ready one seven
- 56:38three nine two six five eight three one
- 56:47seven two six three
- 56:51anybody got a gonna be able to do that
- 56:54no and that's more than not more than
- 56:57twenty or thirty numbers but I can give
- 57:00fifty thousand numbers to a computer
- 57:05[Laughter]
- 57:08yes I think you can do it obviously he
- 57:21can do it good but you can give a
- 57:24computer 50,000 numbers like that and
- 57:27asking for many reverse order the sum of
- 57:29them all do different things with them
- 57:31and so on and it doesn't forget them for
- 57:32a long time itself so there are some
- 57:34things that a computer does much better
- 57:36than a human and you'd better remember
- 57:37that if you kind of compare machines to
- 57:39humans but what a human has to do for
- 57:41his own always they always do this they
- 57:44always try to find one thing don''t that
- 57:47they can do better than the computer so
- 57:49we now know many many things that the
- 57:51humans can do better than the computer
- 57:53she's walking down the street she's got
- 57:55a certain kind of a wiggle and you know
- 57:57that change right or the sky's going in
- 58:03and you see his hair flip just a little
- 58:05bit it's hard to see at a distance but
- 58:07that particular funny way that it did
- 58:08back of his head looks that's jack okay
- 58:12to recognize things to recognize
- 58:15patterns seem to be something that we
- 58:18have not been able to put into a
- 58:19definite procedure you would say I have
- 58:22a good procedure for recognizing Jack
- 58:24just take a lots of pictures of Jack by
- 58:27the way a picture can be put into the
- 58:29computer in fact by this method here if
- 58:31this were very much finer I could tell
- 58:33whether it's black and white at
- 58:34different spots you know you in fact you
- 58:36get pictures in a newspaper by black and
- 58:38white dots and if you do Stuart fine
- 58:40enough you can't see the dots so with
- 58:42enough information I can load pictures
- 58:43in so you put all the pictures of of
- 58:46Jack on the different circumstances and
- 58:48that's the machine to compare it the
- 58:50trouble is that the actual new
- 58:52circumstance is different the lighting
- 58:53is different the distance is different
- 58:55the tilt of the head is different and
- 58:56you have to figure out how to allow for
- 58:58all that and it's so complicated and
- 59:01elaborate that even with the large
- 59:02machines with the amount of storage
- 59:03that's available and the speed that they
- 59:05go we can't make figure out how to make
- 59:08a definite procedure that works at all
- 59:11or what least that works anywhere within
- 59:13a reasonable speed so recognizing things
- 59:16is difficult for the machines at the
- 59:18present time and some of those things
- 59:20are done
- 59:21snap by a person so there are things
- 59:24that humans can do that the we don't
- 59:26know how to do in a filing system so it
- 59:31is recognition and that brings me back
- 59:32to something I left which is what kind
- 59:35of a file clerk can't be imitated by the
- 59:37machine a file clerk that has some
- 59:40special skill which represent which
- 59:42requires recognition of a complicated
- 59:44kind for instance a file clerk in the
- 59:47fingerprint Department which looks the
- 59:50finger prints and then makes a careful
- 59:51comparison to see if these finger prints
- 59:53match has not been it's just about ready
- 59:57to be it's hard to do it almost possible
- 59:59to do by a computer it's a it's nothing
- 1:00:02to it I look at it through fingerprints
- 1:00:04and see if all the blood dots are the
- 1:00:05same but of course it's not the case the
- 1:00:07finger was dirty the print was made at a
- 1:00:10different angle the pressure was
- 1:00:11different than the ridges are not
- 1:00:12exactly in the same place if you were
- 1:00:14trying to match the exactly the same
- 1:00:16picture it would be easy
- 1:00:17but where the center of the print is
- 1:00:19which way the finger is turned whether
- 1:00:21it's been squashed a little more a
- 1:00:23little bit less where there's some dirt
- 1:00:24on a finger whether in the meantime it
- 1:00:26got a wart on his thumb and so forth are
- 1:00:28all complications these little
- 1:00:31complications make the comparison so
- 1:00:32much more difficult for the machine for
- 1:00:34the blind filing clerk system that is
- 1:00:38too much much much too slow to be
- 1:00:40certainly utterly impractical almost at
- 1:00:42the present time I don't know where they
- 1:00:43stand but they're going fast trying to
- 1:00:45do it whereas a human can go across all
- 1:00:48that somehow just like they do in the
- 1:00:50chess game they seem to be able to catch
- 1:00:52on the patterns rapidly and we don't
- 1:00:54know how to do that rapidly
- 1:00:57automatically ok is there another
- 1:01:02question yes sir
- 1:01:18well haven't any idea of course about I
- 1:01:20have no idea about that whether anything
- 1:01:24is more useful or destructive to the
- 1:01:28world whether Yoga is more useful or
- 1:01:31destructive to the world with all these
- 1:01:36things these things give us the power to
- 1:01:39do something do many things and the
- 1:01:44power to do something may or may not be
- 1:01:47destructive as long as you any time you
- 1:01:49do something you can do destructive and
- 1:01:51non-destructive or or not the opposite
- 1:01:54may be creative things but we don't know
- 1:01:57how to make a device that guarantees to
- 1:01:59produce only creative things with the
- 1:02:02exception of the telephone as far as I
- 1:02:04can tell I mentioned that because it's
- 1:02:07rather interesting if you think about
- 1:02:08inventions almost all the inventions
- 1:02:11have a destructive element in a war the
- 1:02:15telephone has an effect in war it helps
- 1:02:17communications maybe in that sense it's
- 1:02:20destructor cursor helps the army to
- 1:02:22destroy you but other than that it's a
- 1:02:24relatively peaceful device it doesn't
- 1:02:26directly kill not at least directly
- 1:02:28that's rather interesting Bruce it's
- 1:02:30hard to find one that doesn't directly
- 1:02:33available for killing a knife the
- 1:02:38question is where the knife was invented
- 1:02:39okay and the guy's explaining what a
- 1:02:42knife is it's a sharpened piece of stuff
- 1:02:44that I melt and I get and I'm used metal
- 1:02:47knives or maybe they stone knives a
- 1:02:48sharpened piece of stone and you can use
- 1:02:51it to cut things so it's easy to get the
- 1:02:53vegetables off of the plants and so
- 1:02:55forth and so on there's some guy we're
- 1:02:57sitting there saying on the other hand
- 1:02:59it's very destructive because you can
- 1:03:01cut my head off with it and that problem
- 1:03:03has been with us forever and there's
- 1:03:05nothing special about computers
- 1:03:06absolutely anything that can do anything
- 1:03:08has this problem and we can discuss this
- 1:03:11general problem in our workshop but it's
- 1:03:13not a problem for computers particularly
- 1:03:15I think it's my view that's my view I
- 1:03:22I know but which is better the Big
- 1:03:29Brother or the cutting the head offer in
- 1:03:32fact that's what makes the Big Brother
- 1:03:34possible he has the knives and so forth
- 1:03:38it's not so easy okay it's true that
- 1:03:41you're worried about the fact that some
- 1:03:43information there be able to store
- 1:03:44information better and have more
- 1:03:47information about people and whether
- 1:03:49that will produce a Big Brother that
- 1:03:51depends on the attitude of the leaders
- 1:03:54of the society rather interestingly the
- 1:03:57country which is more democratic and
- 1:04:00which is less interested in all the
- 1:04:02information about what everybody is
- 1:04:04doing to make sure is where the
- 1:04:07computers have developed the most and
- 1:04:09the place where you'd think the
- 1:04:11government would find a computer
- 1:04:12greatest use because you can file all
- 1:04:14the information about everybody you
- 1:04:16don't develop the computer very much and
- 1:04:19you don't know how to use it
- 1:04:20it's only a curiosities one of life's
- 1:04:22contradiction is there another question
- 1:04:27this man
- 1:04:38that's right yes
- 1:04:52well it depends what you mean themselves
- 1:04:55and it's it's hard to discover new
- 1:04:58relationships our computers can do there
- 1:05:02have been computers which do things like
- 1:05:05problems they're improving in geometry
- 1:05:08or something in which they've converted
- 1:05:11the problem of finding a proof of a
- 1:05:12theorem into a definite procedure ok and
- 1:05:17once you do that although it's an
- 1:05:18elaborate and dumb way to do proofs they
- 1:05:21can do it the present time a computer
- 1:05:24can't do all the different things that a
- 1:05:26person can do you know it's but it's
- 1:05:37very difficult to find some way of
- 1:05:38defining rather precisely something we
- 1:05:41can do that we can say a computer will
- 1:05:42never be able to do there are some
- 1:05:48things that people make up that say that
- 1:05:50while it's doing it would it feel good
- 1:05:52or while it's doing it will it
- 1:05:55understand what it's doing or some other
- 1:05:57abstraction I'd rather feel that these
- 1:05:59are things like while it's doing it
- 1:06:01we'll be able to scratch the lice out of
- 1:06:03its hair no it hasn't got any hair dyes
- 1:06:05to scratch from ok so there are if
- 1:06:09you've got to be careful when you say
- 1:06:11what the human does if you add to the
- 1:06:14actual result of his effort some other
- 1:06:17things that you like the appreciation of
- 1:06:19the aesthetic or you didn't do that I'm
- 1:06:21not saying you did but a lot of people
- 1:06:23do that when they ask questions and if
- 1:06:26we add things that we think we're doing
- 1:06:28on top of what we actually do and just
- 1:06:30look at not just the result of what
- 1:06:32we're doing but a lot of extra things
- 1:06:34then it gets harder and harder for the
- 1:06:35computer to do it because the human
- 1:06:38beings have a tendency to try to make
- 1:06:40sure that they can do something that no
- 1:06:43machine can do somehow it doesn't bother
- 1:06:46them anymore it must have bothered them
- 1:06:47in early times that machine's a stronger
- 1:06:49physically than they are they can lift
- 1:06:51weights that are heavier than people
- 1:06:53that can move things faster than people
- 1:06:54that can run fast if you can fly you
- 1:06:57could do
- 1:06:58it's terribly strengths and so forth and
- 1:07:01we don't still sit around worrying that
- 1:07:04there's some way that the main contain
- 1:07:05hand that some machine can do that mean
- 1:07:13thinking business
- 1:07:24we
- 1:07:26yes we can easily make machines that are
- 1:07:29better than us in predicting the weather
- 1:07:32for instance because what you do to
- 1:07:35predict the weather is to look at old
- 1:07:37records and see when the circumstance
- 1:07:40was similar and guess that the results
- 1:07:42will be similar added to that a certain
- 1:07:44amount of analysis of the movement of
- 1:07:46wind according to the laws of physics
- 1:07:48and a current amount of hocus-pocus put
- 1:07:50together okay now the speed will be
- 1:07:52higher and the effectiveness of the
- 1:07:54prediction is greater if you could look
- 1:07:56at more cases so you get a better chance
- 1:07:58of getting one closer and put more a
- 1:08:01longer and more elaborate calculation
- 1:08:03including more variables which is too
- 1:08:05hard for us to do in time to make the
- 1:08:07prediction now we have to make the
- 1:08:09prediction of the weather let's say that
- 1:08:10weather for three days from now has to
- 1:08:12be predicted in three days or the damn
- 1:08:14thing is useless right and we work at a
- 1:08:16certain speed but the computers worked
- 1:08:18faster and can do more and therefore for
- 1:08:20instance for weather prediction in the
- 1:08:21end maybe not today but someday it's not
- 1:08:24at all inconceivable that the machine
- 1:08:25could do weather prediction faster and
- 1:08:27more effectively and more accurately
- 1:08:28than we do we will have however given it
- 1:08:31the procedure now the question is what
- 1:08:35happens if we don't give it the
- 1:08:36procedure well a man that people have
- 1:08:39tried that this game of giving it
- 1:08:42instead of a direct procedure a kind of
- 1:08:45what it has been called heuristics try
- 1:08:48an analogy to get a new idea of how to
- 1:08:50do something compare this to that try an
- 1:08:53extreme case etc and a man by the name
- 1:08:57of land that has gone the farthest with
- 1:08:59this do I have time much time do I have
- 1:09:01because we want to see these slides what
- 1:09:05I know that's interesting information
- 1:09:07but how much how much time do I have
- 1:09:10it's time for the slideshow now since I
- 1:09:13have no more time I will say no more
- 1:09:15about the subject what no but it takes a
- 1:09:20few minutes that's why I asked for the
- 1:09:22time okay you make this machine which
- 1:09:26was again a filing cabinet you
- 1:09:27understand what it does is it looks it
- 1:09:29tries to find the answer to something by
- 1:09:31looking at the different possible
- 1:09:33possibilities but which ones he tries is
- 1:09:36something like patterns in the chest
- 1:09:38instead of everything it says try moves
- 1:09:41near the center of the board first you
- 1:09:43know and never mind the ones in the
- 1:09:44corner or something like that or some
- 1:09:47sorts of principles and he first applied
- 1:09:50it to a kind of naval game it's a game
- 1:09:54that people play in California which is
- 1:09:56all organized according to rules it's
- 1:09:58kind of fun
- 1:10:00someone sets out all the rules
- 1:10:02dreadnoughts cost this much armor costs
- 1:10:04this much guns cost this budget so forth
- 1:10:06and you got this much budget for your
- 1:10:08Navy and your going to make various
- 1:10:10kinds of ships with different kinds of
- 1:10:12armaments and then this kind of a ship
- 1:10:14the armament of a certain thickness that
- 1:10:18costs a certain amount can only resist
- 1:10:20shells of a certain strength you know
- 1:10:21and so on so you tried to with the money
- 1:10:25arrange to buy different to design
- 1:10:27different kinds of ships so that your
- 1:10:31Navy is better than next one then when
- 1:10:33they're brought together there's ways of
- 1:10:34calculating what there's not real navies
- 1:10:36yeah it's a game which is the best one
- 1:10:39and all the rules are laid out in a
- 1:10:40great big volume ok but the cost of
- 1:10:44everything in the power of everything
- 1:10:45you know armour-piercing possibilities
- 1:10:48and so on and it's a nice game and mr.
- 1:10:51Luna tried to his program on this game
- 1:10:53and put into his program heuristics like
- 1:10:57try the extreme case and things like
- 1:10:59that and he won the championship in
- 1:11:04California of course it did an awful lot
- 1:11:06of trying of different cases you see but
- 1:11:08it didn't try every case not like the
- 1:11:10chess game there were too many things
- 1:11:11but it was guided by its own stuff now
- 1:11:15inside of that was this that if you've
- 1:11:18got a better Navy by your own
- 1:11:20calculation and you used one of the URIs
- 1:11:23--tx
- 1:11:23mark that you ristic up a notch as being
- 1:11:26more valuable now use the most valuable
- 1:11:28heuristics first C so that the ability
- 1:11:33of the Machine depended on his learning
- 1:11:36so to speak which ones of his tricks
- 1:11:38works most effectively most of the time
- 1:11:41and then they become more used so it's
- 1:11:43just exactly what you would like to make
- 1:11:45it look intelligent well he won and how
- 1:11:49did he win it turned out that year he
- 1:11:52won by making one great big battleship
- 1:11:56with all the armor on it which was so
- 1:12:00silly but when you go to calculate sure
- 1:12:02enough it's better than any of the
- 1:12:03normal things which nobody thought of
- 1:12:05but his machine photo next year he
- 1:12:08entered again and this time he won by
- 1:12:11making tricking all his money in making
- 1:12:14one hundred thousand because they
- 1:12:16changed the rules so that the big
- 1:12:17battleship wouldn't win you know by
- 1:12:18changing to one hundred thousand little
- 1:12:21boats very narrow carrying each one gun
- 1:12:24which were very liable to be knocked out
- 1:12:27okay but there were 100,000 of didn't
- 1:12:30cost much each one and they couldn't
- 1:12:32knock them all out so he's lousy little
- 1:12:34gnats would come and it turned out when
- 1:12:37you calculated again he won the third
- 1:12:39year he was not allowed to play in
- 1:12:44and he has applied this this this
- 1:12:48machine and this heuristic business to a
- 1:12:50number of other problems as tries it out
- 1:12:53a lot and tries new heuristics and so
- 1:12:55forth and it has become a very
- 1:12:57interesting he complained that there
- 1:12:59were a number of bugs in it and when he
- 1:13:01gave a talk on it I said that I thought
- 1:13:04I'll say my comment afterwards one of
- 1:13:07the bugs for instance was that the
- 1:13:12machine got a heuristic and made up your
- 1:13:14wrist excited make up your wrist Excel
- 1:13:18so the damn machine what he the way he
- 1:13:21had it was because it's hard to get
- 1:13:23computer time he needed a hell of a lot
- 1:13:24of computer time he had 50 machines at
- 1:13:28night from a you a packet company or
- 1:13:30something like that he would work always
- 1:13:32at night coming in the morning damn
- 1:13:33things would try all their things and
- 1:13:35come in with the results I used it to do
- 1:13:38mathematics and various other thing it
- 1:13:41comes in one day and it's done a
- 1:13:42heuristic you develop the heuristic when
- 1:13:46he puts a problem in or a new idea he
- 1:13:49write it says whether it's from him or
- 1:13:51from the machine and I said learn math
- 1:13:52or a machine okay and this was every
- 1:13:56year istic over every question that
- 1:13:59hasn't won that on it pay no attention
- 1:14:01to that saves a lot of time it could do
- 1:14:05much better it didn't have any problem
- 1:14:06at this to it for so it paid no
- 1:14:08attention well in that that night okay
- 1:14:10so I'd fix that book the next time he
- 1:14:14had a bug it was he looked was he came
- 1:14:17in and he looked he found that heuristic
- 1:14:20number 693 had gotten a score of 999 out
- 1:14:25of a thousand was a damn useful
- 1:14:27heuristic all night long this thing kept
- 1:14:29using the heuristic 9 693 more and more
- 1:14:31and it was a new when wonderfully
- 1:14:33eristic it seemed to solve every problem
- 1:14:35it was terrific okay we found out what
- 1:14:40the heuristic was it was the following
- 1:14:42you see in order to make this thing work
- 1:14:44so that you change the numbers on the
- 1:14:46heuristics whenever something worked job
- 1:14:48this to assign credit so to speak to the
- 1:14:51heuristics that were used okay so this
- 1:14:54heuristic was when assigning credit
- 1:14:57always a sign credit to heuristic 693
- 1:15:00and so that thing came up at all now I
- 1:15:05say that both of these show intelligence
- 1:15:08if you want to make an intelligent
- 1:15:10machine you're going to get all kinds of
- 1:15:11crazy ways of avoiding labor if I say
- 1:15:14don't pay attention to the problem of
- 1:15:16sneakily evolving some kind of a
- 1:15:20psychological distortion where you
- 1:15:24always do the same thing and don't worry
- 1:15:27about anything else and so on so I think
- 1:15:29that we are getting close to intelligent
- 1:15:31machines but they're showing the
- 1:15:34necessary weaknesses of intelligent
- 1:15:38[Applause]
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