00:00:00.000 Area correction is the most important method in technology and learning in general.
00:00:09.160 In biological evolution, it appears to be the only means of progress.
00:00:14.240 One rightly speaks of the trial and error method, but this understates the importance
00:00:25.760 All organisms are inventors and technicians, good or not so good, successful or not so
00:00:34.320 This is how it is among animals, spiders, for example.
00:00:37.800 Human technology solves human problems such as sewage dispersal, or the storage and supply
00:00:42.560 of food and water as, for example, bees already have to do.
00:00:47.040 Hostility to technology, such as we often find among the grains, is therefore a foolish
00:00:51.880 kind of hostility to life itself, which the grains have unfortunately not realised.
00:00:58.040 But the critique of technology is not foolish of course, it is urgently necessary.
00:01:03.320 Everyone is capable of it in their different ways, and most welcome to contribute.
00:01:08.480 And since criticism is an occupational skill of technologists, the critique of technology
00:01:17.360 While Papa, from the essay, all life is problem-solving from the book of the same title or
00:01:45.520 So welcome to topcast and episode 90, I think, certainly part two of chapters three, problem-solving
00:01:55.760 And I began there with what Karl Popper had to say about problem-solving, namely, all life
00:02:03.560 And what I understand he meant by this is not only that every single thing in a human
00:02:08.880 life is about problem-solving, you are continually trying to solve different problems.
00:02:14.440 But not only a way in which to avoid suffering the bad things in life, but also a way in
00:02:21.160 If you had a situation where you had no problems or you weren't trying to solve anything,
00:02:26.120 then as David Deutsch says in the beginning of infinity, the other name for a problem-free
00:02:32.840 We are constantly trying to solve the problem of how to be warmer and more comfortable,
00:02:38.120 how to be more interested or interesting, what to do next is often a problem for us,
00:02:43.760 how to solve a particular scientific problem, how to go about our work lives, how to go
00:02:47.640 about our family and social lives, how to get out of pandemics and difficult situations,
00:02:52.400 we find ourselves in, how to find out which of the interesting things and opportunities
00:02:57.080 that we have before us might be best for us to pursue.
00:03:00.720 But of course, it's not only about humans, it's about every single living organism.
00:03:05.040 So we can also take all life is problem-solving to, that's literally what life is trying to do,
00:03:09.640 trying to solve the problem of keeping itself in existence, individual organisms are kind
00:03:14.120 of trying to do that to some extent, really it's the genes, trying to get themselves replicated.
00:03:18.440 However, life, whether it's our human lives personally or life broadly speaking, as broadly
00:03:24.800 as you can conceive it, it's about problem-solving.
00:03:28.280 And in part one of my discussion of this chapter, we eventually got to a universal scheme,
00:03:35.800 which I'll put up on the screen now, a universal scheme for the solving of problems.
00:03:40.680 And this scheme that David is setting out, it's a practical vision for problem-solving.
00:03:48.320 As he will say, this applies to every topic, no matter the subject matter.
00:03:52.240 And of course, it applies importantly to people's personal lives, to business, to something
00:03:56.240 like police detective work, as well as science, history, mathematics, philosophy and so on.
00:04:01.200 What separates science in this scheme is the existence of crucial experimental testing.
00:04:07.920 So let's pick it up where David writes, quote, what I have described so far applies to
00:04:13.480 all problem-solving, whatever the subject matter or techniques of rational criticism that
00:04:18.800 are involved, scientific problem-solving always includes a particular method of rational
00:04:24.880 criticism, namely experimental testing, where two or more rival theories make conflicting
00:04:30.920 predictions about the outcome of an experiment, the experiment is performed, and the theory
00:04:36.080 of theories that made false predictions are abandoned.
00:04:39.400 The very construction of scientific conjectures is focused on finding explanations that
00:04:47.880 Ideally, we are always seeking crucial experimental tests.
00:04:52.040 Experiments whose outcomes, whatever they are, will falsify one or more of the contending
00:04:58.080 Now, to learn more about the idea of falsifying one or more, ideally all the other rivals,
00:05:05.680 leaving only one standing, then consult David's seminal paper, titled, in part at least,
00:05:12.080 the logic of experimental tests, or my own guide to the paper, which is simply called
00:05:17.920 I call it that because it seemed to me at the time, and it still does, that this was the
00:05:23.120 crown jewel so far as that subject, the philosophy of science, is concerned, it takes Galileo,
00:05:29.000 Galilei, and his writings, his work on cemential trials, up through Francis Bacon, who,
00:05:34.960 along with Locke, pioneered empiricism, through to Popper and his work on demarcation and
00:05:39.920 conjectural knowledge, and finally, all the way up to David Deutsch, and his hard to very
00:05:45.360 good explanations in the nature of what's called a crucial experimental test.
00:05:53.640 This process is illustrated in figure 3.3, whether or not observations were involved in
00:05:58.480 the instigating problem, stage one, and whether or not in stage two, the contending
00:06:03.120 theories were specifically designed to be tested experimentally.
00:06:07.640 It is in this critical phase of scientific discovery, stage three, that experimental tests
00:06:16.360 That role is to render some of the contending theories unsatisfactory by revealing that
00:06:22.520 their explanations lead to false predictions, that bears repeating, or say it again, that
00:06:31.040 role, the role of experimental tests, is to render some of the contending theories unsatisfactory
00:06:38.360 by revealing that their explanations lead to false predictions.
00:06:44.000 Here I must mention an asymmetry, which is important in the philosophy and methodology
00:06:47.440 of science, the asymmetry between experimental refutation and experimental confirmation.
00:06:55.120 Whereas an incorrect prediction, automatically renders the underlying explanation unsatisfactory,
00:07:01.400 a correct prediction says nothing at all about the underlying explanation, like I just
00:07:05.880 pausing their my reflection, when you have this disagreement between an experimental
00:07:11.040 result, an incorrect prediction, in other words, and the theory itself, which makes
00:07:17.360 that prediction, so you have this clash between an experimental result and a theory, then
00:07:25.520 Now it doesn't mean that the theory itself is necessarily logically wrong.
00:07:30.440 It means the underlying explanation, which is the explanation of what's going on in the experiment,
00:07:39.040 So these two things together, there's a conflict there, so the explanation of the whole
00:07:44.240 Now the standard way of understanding this is to, of course, say, well, the experimental
00:07:51.240 And that is typically how science works, but it's also an ideal about how science works.
00:07:55.440 It could be the case that the experimenters flawed, but whatever the case, whether it's
00:07:58.800 experiment that's flawed, or whether it's the theory that's flawed, the underlying explanation
00:08:03.640 of the conjunction of those two things is flawed.
00:08:08.240 Now this also bears repeating that last thing that I read, a correct prediction says nothing
00:08:14.000 at all about the underlying explanation, such an important point, easily missed by lay
00:08:20.920 people in science, but sometimes scientists themselves.
00:08:24.280 There is this asymmetry, as David has said there, between experimental refutation and
00:08:32.560 And we might, without any loss of meaning, simply add the word apparent there.
00:08:37.320 It is an apparent confirmation whenever you see a confirmation.
00:08:41.720 After all, what does it mean to confirm something?
00:08:44.680 Well, philosophically, and absolutely worse, putting it in its worst possible light
00:08:50.000 so to speak, confirm or confirmation could mean to show as actually being true something
00:08:57.600 or other, so if you confirm a theory by observation, you have shown that theory to be true,
00:09:05.360 Why that people talk, okay, I was listening to, I know he's not a scientist, but somebody
00:09:11.200 who has studied some philosophy and I think represents common understandings on this thing
00:09:16.080 is the comedian Ricky Javez, and he talks in this way.
00:09:18.960 He talks about confirming a theory and confirming a theory as true and knowing that something
00:09:22.960 is true and so on and so forth, and I think that's, I'm just using him because that's
00:09:27.040 a good example of the way I think another one majority of people think on these topics.
00:09:33.040 And he's someone with actual philosophical training and someone who indeed talks to prominent
00:09:39.640 So it could mean that, it could mean that confirm means to show something as actually true,
00:09:43.680 which any preparing will of course say, well this is impossible, it's an impossible
00:09:46.720 standard so we can throw confirm into the bin, we don't need it.
00:09:50.840 But if I was to try and steal man that position, that confirm doesn't need to mean something
00:09:57.080 like show absolutely and finally true, it could mean something like this observation
00:10:02.960 and conforms to that theory and therefore lends credence to it, which is a fancy way of
00:10:08.920 kind of saying shows it more likely to be true without showing it finally true, which
00:10:17.760 Now Popper himself in various places, logical scientific discovery, objective knowledge, various
00:10:22.360 other things and places that he's written about this.
00:10:25.360 He makes a big deal about this, about the whole idea of rejecting confirmation, of course
00:10:29.680 he's right to do so, but it seems to me that he wants to still have the word, still
00:10:36.000 meet the media's opposition half way and so he comes up with this word corroborate and
00:10:41.000 so he uses the word corroborate instead of confirm and says, well we can use the idea
00:10:46.960 of experiments that agree with a particular theory corroborate the theory and of course
00:10:51.160 if you get a dictionary and you look up or corroborate means, it means something like
00:10:54.680 confirm, so I think it gets him very far, because whether it's confirm or corroborate,
00:11:00.200 it seems to imply some kind of possibility of support for a theory and you can't support
00:11:05.480 a theory by which we mean the theory isn't justified, the theory isn't absolutely true
00:11:11.240 in any way, shape or form, the best that I can say for what Popper is saying about
00:11:15.240 corroboration in this case is that he's kind of talking about how some theories really
00:11:22.200 do stick their neck out in a way and then don't get falsified by experiment which can
00:11:28.440 be telling, you know it says something, it's not completely contentless that information
00:11:33.240 when a particular theory makes a risky prediction and gets the prediction right or rather
00:11:39.800 doesn't get falsified by the experiment as the way I would better say it, so for example
00:11:44.120 the classic case of testing how much light bends during a solar eclipse you know this
00:11:50.280 Eddington's experiment to distinguish between whether general relativity is the best theory
00:11:54.600 or Newtonian gravity, on this view about corroboration you would say well general relativity
00:11:59.160 is corroborated by the correct prediction about how much the light bends, I don't know
00:12:04.760 that it adds that much given what Popper says elsewhere about how well the best explanation is of
00:12:11.320 course general relativity and once that experiment that crucial test Eddington's experiment
00:12:16.760 refutes shows as inadequate Newton's theory of gravity therefore we say it falsifies Newton's
00:12:23.800 theory of gravity, you don't need to use this word confirm corroborate support anything like
00:12:29.240 that because the only theory you have left standing is general relativity there are no rivals
00:12:34.680 it doesn't need support because heck it's the only one we've got what more do you want
00:12:39.560 then the best theory the only theory that is there before you with regards to what the nature
00:12:46.360 of gravity is it can do all the explanatory work that you need and it can do all the predictive work
00:12:51.880 that you need until such time as you find a problem with it so I don't think any of this is needed
00:12:56.360 again I think that Popper's just conceding a certain amount of ground to his opponents politely
00:13:03.720 so that the conversation can keep on going because they of course are absolutely enamored by this
00:13:09.560 idea of justification and support and confirmation and so he's throwing them a bone I suppose
00:13:14.600 perhaps it'll be good to be able to ask him the fact is that in many of these cases we have
00:13:19.800 in case of gravity we have an explanation of gravity an existing best explanation of gravity
00:13:26.680 emphasis on the an okay there's not multiple excellent explanations of gravity there's one
00:13:32.840 so it doesn't matter how often it gets corroborated you know it makes these risky predictions
00:13:37.160 because it's already the only existing theory so it doesn't need more support it just
00:13:41.400 is the theory now is it true is it finally true no we've been through that of course it's not
00:13:45.480 finally true it's just the best it contains some truth about reality but you know how does being
00:13:53.640 consistent with predictions help well let's go back to the book David writes quote shorty
00:13:59.480 explanations that yield correct predictions are too a penny as UFO enthusiasts conspiracy theorists
00:14:06.280 and pseudo scientists of every variety should but never do bear in mind okay pausing
00:14:11.640 they're just a little comment on that bit so for example a person who believes aliens are visiting
00:14:16.920 us will be able to confirm or corroborate if you like their belief that namely the pictures of
00:14:23.560 UFOs that are sometimes published are consistent with the existence of aliens visiting earth
00:14:29.400 from another galaxy via spacecraft that travel beyond the speed of light or something like that
00:14:33.880 they don't look for refutations they look for consistency with their already existing theory
00:14:41.080 they look for confirmation now some scientists and some people who regard themselves critical
00:14:46.520 thinkers call this an example of confirmation bias but of course I would say it's just the
00:14:52.600 error of thinking that confirmation is even a thing at all many many scientists do indeed think
00:14:58.600 that it is a thing and I think that's a kind of bias of a kind they think that too much
00:15:05.640 confirmation is a bad thing but just the right amount of confirmation is a good thing that's possible
00:15:10.520 it's possible to have a little bit of confirmation but not too much confirmation then you have
00:15:13.480 confirmation bias so there's there's almost like there's an ideal amount of confirmation on this
00:15:18.440 view basing epistemology is kind of like this you know it says that some stuff is a confirmation of
00:15:25.480 the theory not a finally true confirmation of a theory just a probabilistic confirmation of the
00:15:30.760 theory and the more you have confirmation the more confident you become that this particular theory
00:15:35.800 is the correct theory we don't usually need that because again we only ever have one good
00:15:42.840 explanation at any given time and in the rare cases where we have two then we do a crucial test
00:15:48.440 ruling out one of them and holding up the one as the explanation not the finally true explanation
00:15:54.440 I'm repeating myself so whatever the case what we're after are refutations where we can get them
00:16:02.360 not confirmations because confirmation is impossible back to the book David writes quote
00:16:09.000 if a theory about observable events is untestable that is if no possible observation would rule it
00:16:15.160 out then it cannot by itself explain why those events happen in the way they are observed to
00:16:21.320 and not in some other way for example the angel theory of planetary motion is untestable because
00:16:27.720 no matter how planets moved that motion could be attributed to angels therefore the angel theory
00:16:33.640 cannot explain the particular motions we see unless it is supplemented by an independent theory of
00:16:39.640 how angels move that is why there is a methodological rule in science which says that once an
00:16:46.040 experimentally testable theory has passed the appropriate tests any less testable rival theories
00:16:51.880 about the same phenomena are summarily rejected for their explanations are bound to be inferior
00:16:57.720 this rule is often cited as distinguishing science from other types of knowledge creation
00:17:03.160 but if we take the view that science is about explanations we see that this rule really is a
00:17:08.840 special case of something that applies naturally to all problem solving theories that are capable
00:17:14.680 of giving more detailed explanations are automatically preferred that bears repeating again
00:17:21.240 theories that are capable of giving more detailed explanations are automatically preferred
00:17:26.920 they are preferred for two reasons one is that a theory that sticks its neck out by being more
00:17:32.360 specific about more phenomena opens up itself and its rivals to more forms of criticism
00:17:39.480 and therefore has more chance of taking the problem solving process forward the second is
00:17:44.600 simply that if such a theory survives the criticism it leaves less unexplained which is the object
00:17:51.000 of the exercise okay pausing there and an example I did a much rope example Newtonian gravity
00:17:58.520 said that gravity is this force that varies as the product of the masses involved
00:18:05.240 divided by the square of the distance between the masses and in stating something true about gravity
00:18:12.360 something approximately true about gravity it reached beyond whatever Newton was specifically
00:18:19.640 interested in the particular problem he was interested in across the whole solar system across
00:18:25.960 the galaxy to every single where in the universe and every single when in the universe it reached
00:18:31.160 into how the tides work and how planets moved and how rocks fell to the ground when they were
00:18:37.640 dropped and so on and so forth however it could not explain certainly not adequately
00:18:44.920 things like modern day examples of gravitational lensing or the existence of neutron stars or
00:18:51.560 black holes or the procession of orbits or gravitational waves or if you want to get really fancy
00:18:57.560 lens throwing frame dragging which is where space time itself is literally dragged by a massive
00:19:03.000 body when it's rotating much less all the stuff that couldn't even be imagined in the
00:19:07.320 previous paradigm you know the previous idea of how physics worked gravity as well as space and
00:19:13.240 time you couldn't even imagine things like the relativity of simultaneity length contraction and
00:19:19.000 time dilation so all those phenomena amount to predictions of a kind given general relativity
00:19:25.480 arising out of a far more detailed explanation of the nature of gravity in general relativity
00:19:31.240 over Newtonian gravity which was less detailed it general relativity sticks its neck out in many
00:19:37.400 directions or you can think modern medicine compared to focal ancient or pseudoscientific nostrums
00:19:43.640 drink this herbal tea or wear this magic pendant to ward off your illness is one thing
00:19:49.400 one level of non explanation so to speak but take this paracetamol because it inhibits
00:19:54.680 prostagland and synthesis preventing the creation of enzymes that cause pain receptors to be
00:19:59.320 activated is something else entirely especially when it works more often than not over those nostrums
00:20:05.640 okay back to the book in David writes I have already remarked that even in science most criticism
00:20:12.680 does not consist of experimental testing that is because most scientific criticism is directed
00:20:17.640 not other theories predictions but directly at the underlying explanations testing the predictions
00:20:23.160 is just an indirect way albeit an exceptionally powerful one when available of testing the
00:20:29.000 explanations in chapter one I gave the example of the grass cure the theory that eating a
00:20:33.480 kilogram of grass is a cure for the common cold that theory and an infinity of others of the same
00:20:39.400 ilk are readily testable but we can criticize and reject them without bothering to do any experiments
00:20:45.640 purely on the grounds that they explain no more than the prevailing theories which they contradict
00:20:50.520 yet make new unexplained assertions the stages of a scientific discovery shown in figure
00:20:56.680 3.3 a seldom completed in sequence at the first attempt there is usually repeated backtracking
00:21:02.920 before it stages completed or rather solved for each stage may present a problem whose solution
00:21:08.840 itself requires all five stages of a subsidiary problem solving process just pausing that yes
00:21:16.120 my reflection on this is that that scheme or any scheme that you want to write out is subject to
00:21:23.080 revision and modification within actual science as it's practiced and so there's no real method of
00:21:29.800 science you're taught this in school follow the scientific method people talk about the scientific
00:21:33.480 method the method is if there is one way of doing things one way of reaching discovery we know
00:21:38.440 this isn't true because we know all no stories of so-called serendipity in science I think too much
00:21:43.640 is often made of serendipity the people that make the biological breakthroughs are often
00:21:48.680 biologists and that's not me luck that their biologist they've made the conscious choice to go into
00:21:53.160 that area but you speak to biologists about famous cases for example the discovery of penicillin let's
00:21:58.760 say it's the trope example where luck was apparently involved and how does luck feature into
00:22:04.920 this scientific method well the scientific method really is about the methods of criticism putting
00:22:10.200 all that aside I remember one of the first essays I ever wrote on the philosophy of science
00:22:15.720 was in response to a question which I cannot remember what the question was about the logic of
00:22:21.400 scientific discovery pop is first book and it's not a great in road to pop is work as I think I might
00:22:28.920 have commented on here before it's very technical it's dense it's not particularly an enjoyable
00:22:34.200 read like so many of his other ones are there so much more clear and especially as a person who was
00:22:39.320 very beautiful philosophy reading any kind of philosophy was a bit of a struggle but in my essay
00:22:45.320 I did manage to conclude that in a sense pop is own title of his work was in a sense misleading
00:22:53.320 because there was no logic to scientific discovery if you buy what you mean by logic is something
00:22:59.560 more like a deductive process of course he calls it a hyperthetico deductive process because it's
00:23:05.240 it's kind of the use of what's called modus tolens which is where you well it's refutation okay
00:23:11.880 if the theory leads to particular prediction and the prediction turns out to be false then the theory
00:23:16.280 can show itself to be false but whatever the case it's not like you're putting observations in
00:23:21.080 at the front of this scientific method and getting out the end scientific theories that kind of
00:23:27.720 program just doesn't work so what you're taught in school about write down your observations
00:23:33.960 and at the end of it reach a conclusion no that you have to start with a guess of some sort
00:23:40.440 and the guess should be an explanation of some kind but when I wrote this essay happily for me
00:23:45.240 the professor seems to agree the point here is that David is pointing out what popper does
00:23:51.080 that creativity in science is messy and not formulaic there are heuristics that one might apply
00:23:58.600 of course experimental testing is essential to the whole project of remarketing science from
00:24:04.040 everything else but you're going to go back and forth between these stages of what might be
00:24:10.360 referred to as cycles of creativity and criticism and only at the end of all these cycles might
00:24:17.720 you get something called scientific knowledge at the end of it like looking at the scheme here we've
00:24:22.680 got the five stages problem well number one how do we know that we've got a problem in the first
00:24:28.840 place that takes a certain amount of creativity of recognizing of seeing before you you have a
00:24:33.800 theory and you have an observation and these things don't seem to agree with each other but you
00:24:39.000 have to creatively conjecture what's going on before you as to whether or not that really is a
00:24:44.520 problem or whether or not you've simply made a mistake we're just still a problem two step two is
00:24:50.200 more creativity conjecturing a solution this can be the hardest part of all the entire scientific
00:24:55.400 exercise that even if you do find this problem then being able to solve the problem well that's
00:25:01.480 a whole other step that's a whole other level many many physicists might have observed that mercury
00:25:09.560 is all but wasn't being correctly predicted by Newtonian gravity they could all agree and check
00:25:15.240 for themselves that this prediction seemed to be inaccurate and they were coming out with conjectured
00:25:19.320 solutions some of which included other planets that were yet to be observed perturbing the
00:25:24.680 orbit of mercury but it took the genius of Einstein to solve it lots of scientists might have thought
00:25:31.000 how do we have this diversity of species on the planet is there this thing called evolution but it
00:25:35.800 could took the genius of down to figure out this is thing called natural selection evolution by
00:25:40.280 natural selection so on and so forth when we get to parts three and I'm going to mention more on
00:25:46.040 this later we've got criticism including experiments test that can require an equal amount of
00:25:52.200 creativity simply devising the experiment can be one of the hardest parts of this entire enterprise I
00:25:57.960 asked David a question about this actually one of my questions for David and he talked about how
00:26:03.800 yes you know you people underestimate just how difficult some experiments can be to do so anyway
00:26:11.880 all this entire scheme this one through five scheme all of it requires a significant amount of
00:26:17.800 creativity there's no formula to it and you're going to go backwards and forwards between
00:26:21.640 thinking there's a problem recognizing perhaps there's not a problem thinking there's a problem
00:26:25.320 again coming up with a solution realizing the solution doesn't seem to work because you've
00:26:29.960 conjectured a particular kind of criticism and the criticism has been valid or invalid and so it goes
00:26:35.640 I mean it can be a very messy process which of course or brings us to the idea that
00:26:41.000 scientists and scientific progress needs time it can't be this standard kind of a job with other
00:26:49.720 people might be in where you're working in a factory and you're doing a similar thing over and
00:26:54.600 over again day after day or even in the media where you're just reporting on things that you
00:26:59.640 see in front of you and coming up with a story and the stories are going to move on tomorrow so
00:27:05.000 it doesn't matter if you made a mistake yesterday you just keep moving forward moving forward
00:27:08.920 but science can't be quite like that you know it's very difficult to try and
00:27:15.000 e-count a little bit of truth in the mess of falsehoods and errors that you're surrounded with
00:27:20.760 that can be hard and so David talks a little about this this going backwards and forwards
00:27:24.760 but I'm going to skip most of that part where he discusses this moving between the stages that he
00:27:31.400 has here except to mention that also he talks about stage three there which is so important
00:27:38.360 with the the idea of criticism here in science you might need to invent new modes of criticism
00:27:44.600 they might have to be a new way of coming up with a scientific theory as I flagged earlier
00:27:49.880 and so that can just be extremely difficult to do and that can lead to sub-problems the sub-problem
00:27:56.280 of how to come up with the new experiment how to figure out how to solve the problems in the experiment
00:28:02.440 so often in physics at least it's very difficult to see the effect that you want to see
00:28:08.200 there's the famous Mickelson Morley experiment to try and detect the so-called ether this
00:28:15.640 material through which light waves would propagate it used among other things in interferometer
00:28:21.960 now forgetting putting aside exactly what the experiment sought to establish and failed to
00:28:28.040 establish the existence of the ether this thing we either wind rather just trying to set the whole
00:28:33.880 thing up to get it to work in the first place the engineering problems were so difficult I think
00:28:38.520 the entire experiment had to sit in a bath of mercury liquid mercury and because it's an interferometer
00:28:44.840 it's looking at interference effects with light that's extremely difficult I trust me from
00:28:50.200 experience that you try and do experiments on the interference of light and it's very difficult to
00:28:54.440 see little own measure what's going on it's a very subtle effect so much in physics about
00:29:00.360 subtle effects difficult to observe effects and to pick them up you often need to invent
00:29:05.640 new instrumentation or faster computers you know my own very very modest inroads into doing
00:29:12.440 kind of experiments required me to figure out whether or not these two particular galaxies were
00:29:17.320 going to merge or pass through one another and the number of parameters that you needed to change
00:29:22.920 for each galaxy kind of ballooned exponentially the more accurate you wanted your prediction today
00:29:30.520 and in particular the more stars you had in your simulated galaxies the higher the computing
00:29:35.960 power that you needed which again is more ways of changing the experiment and so more
00:29:41.080 creativity is required in order to try and use a slower computer in order to figure out what
00:29:46.440 and otherwise faster computer might have been able to tell you and so this is kind of a sub-problem
00:29:52.360 so I'll pick it up where David says quote not only is there constant backtracking but the many
00:29:58.200 sub-problems all remain simultaneously active and are addressed opportunistically it is only when
00:30:03.880 the discovery is complete that a fairly sequential argument in a pattern something like figure
00:30:09.480 3.3 can be presented it can begin with the latest and best version the problem then it can show
00:30:15.800 how some of the rejected theories fail criticism then it can set out the winning theory and say why
00:30:21.720 it survives criticism then it can explain how one copes without the superseded theory and finally it
00:30:27.080 can point out some of the new problems that this discovery creates or allows for while a problem is
00:30:33.080 still in the process of being solved we are dealing with a large heterogeneous set of ideas
00:30:38.840 theories and criteria with many variants of each all competing for survival there is a
00:30:44.040 continual turnover of theories as they are altered or replaced by new ones so all the theories are
00:30:49.960 being subjected to variation and selection according to criteria which are themselves subject
00:30:57.000 to variation and selection the whole process resembles biological evolution a problem is like an
00:31:03.800 ecological niche and a theory is like a gene or a species which is being tested for viability in
00:31:10.120 that niche or niche variance of theories like genetic mutations are continually being created
00:31:17.880 and less successful variants become extinct when more successful variants take over success
00:31:23.400 is the ability to survive repeatedly under the selective pressures criticisms brought to bear
00:31:30.040 in that niche and the criteria for that criticism depends partly on the physical characteristics of
00:31:35.640 the niche and partly on the attributes of other genes and species i.e. other ideas that are already
00:31:41.960 present there the new worldview may be implicit in a theory that solves a problem and the distinctive
00:31:48.360 feature of a new species that it takes over a niche are emergent properties of the problem on niche
00:31:53.720 in other words obtaining solutions is inherently complex there is no simple way of discovering the
00:31:59.160 true nature of planets given say i critique the celestial sphere theory and some additional
00:32:04.280 observations just as there is no single way of designing the DNA of a koala bear given the
00:32:09.480 properties of eucalyptus trees just pausing there i know in the Australians listening to this
00:32:15.400 will book the idea of a koala bear we are metaphorically bashed over the head as children that koala
00:32:21.960 is not bears but we can forgive this the use is kind of like teddy bear i mean a teddy is not a bear
00:32:28.120 either so but nonetheless i think it's so quite fine to use that terminology going on
00:32:34.200 david rats quote evolution or trial and error especially the focused purposeful form of trial
00:32:41.000 and error called scientific discovery are the only ways for this reason proper called his theory
00:32:46.680 that knowledge can grow only by conjecture and refutation in the manner of figure 3.3
00:32:51.080 an evolutionary epistemology this is an important unifying insight and we shall see that there are
00:32:56.600 other connections between these two strands what are the strands just to me here the strands are
00:33:03.720 epistemology and biological evolution or evolution by natural selection okay but david goes on to say
00:33:10.040 quote but i did not want to overstate the similarities between scientific discovery and biological
00:33:15.480 evolution for their important differences too one difference is that in biology variations or
00:33:21.000 mutations a random blind purposeless while in human problem solving the creation of new conjectures
00:33:27.160 is itself a complex knowledge laden process driven by the intentions of the people concerned
00:33:33.000 perhaps an even more important difference is that there is no biological equivalent of argument
00:33:38.680 all conjectures have to be tested experimentally which is one reason why biological evolution
00:33:44.520 is slower and less efficient by an astronomically large factor pausing there i'm just my
00:33:51.800 reflection on that we're just rather my emphasis here because conjectures which in biology
00:33:59.080 amount to gene mutations must themselves be tested individually so each time an organism
00:34:07.800 the variation between organisms within a species amount to a kind of gene mutation
00:34:15.320 from one species to another each of them gets tested in the environment and because each of
00:34:20.360 them are getting tested tested by the measure that the organism itself does not survive so it goes
00:34:26.520 through its natural life or whatever okay which usually some years that's a very slow process
00:34:33.720 but as David has been pains to say here we criticize explanations without ever needing to
00:34:41.320 actually test them necessarily in the real world so often whereas biological evolution only
00:34:47.640 ever does that testing in the real world okay we can we can cut through and just look at the
00:34:52.680 quality of the explanation rather than constructing the experiment which as i've just said
00:34:57.880 and explained itself is a creative process which requires quite a lot of effort to do it's not
00:35:03.560 trivial to do especially these days scientific experiments back to the book nevertheless
00:35:10.920 the link between these two sorts of process is far more than mere analogy they are
00:35:17.000 two of my four intimately related main strands of explanation of the fabric of reality both in
00:35:22.680 science and in biological evolution evolutionary success depends on the creation and survival of
00:35:29.480 objective knowledge which in biology is called adaptation that is the ability of a theory or a
00:35:35.480 gene to survive in a niche is not a haphazard function of its structure but depends on whether
00:35:41.400 enough true and useful information about the niche is implicitly or explicitly encoded there
00:35:47.560 i shall say more about this in chapter eight okay now i'm skipping a small amount and i'm going
00:35:54.120 to where David says quote take a moment to compare figures 3.1 and 3.3 look how different
00:36:01.800 these two conceptions of the scientific process are inductivism is observation and prediction
00:36:09.000 based whereas in reality science is problem and explanation based inductivism supposes that
00:36:16.520 theories are somehow extracted or distilled from observations or justified by them whereas in fact
00:36:22.920 theories begin as unjustified conjectures in someone's mind which typically precede the observations
00:36:29.960 that rule out rival theories inductivism seeks to justify predictions as likely to hold in the future
00:36:37.960 problem solving justifies an explanation as being better than other explanations available in the
00:36:43.720 present inductivism is a dangerous and recurring source of many sorts of error because it is
00:36:51.000 superficially so plausible but it is not true i'll say that again inductivism is a dangerous and
00:36:59.240 recurring source of many sorts of errors because it is superficially so plausible okay and then David
00:37:05.800 goes on to say quote when we succeed in solving a problem scientific or otherwise we end up with a
00:37:12.920 set of theories which though they are not problem-free we find preferable to the theories we started
00:37:18.520 with what new attributes the new theories will have therefore depends on what we saw as the
00:37:25.400 deficiencies in our in our original theories that is on what the problem was science has characterized
00:37:31.400 by its problems as well as by its method astrologists has solved the problem of how to cast more
00:37:37.240 intriguing horoscopes without risking being proved wrong are unlikely to have created much that
00:37:43.560 deserves to be called scientific knowledge even if they have used genuine scientific methods
00:37:49.000 such as market research and are themselves quite satisfied with the solution the problem in genuine
00:37:54.760 science is always to understand that some aspect of the fabric of reality by finding explanations
00:38:00.840 that are as broad and deep and as true and specific as possible when we think that we have solved
00:38:07.640 a problem we naturally adopt our new set of theories and preference to the old set that is why
00:38:13.000 science regarded as explanation seeking and problem solving raises no problem of induction there is
00:38:20.120 no mystery about why we should feel compelled tentatively to accept an explanation when it is the
00:38:25.880 best explanation we can think of end quote end of the chapter there isn't that brilliant there
00:38:33.000 in that last paragraph we have encapsulated so much which is in the beginning infinity so much
00:38:39.080 that is in poppers work so much that today motivates people who follow in this particular
00:38:45.880 mold of the way in which we understand how knowledge is created science is the process the
00:38:54.200 methodology of science science it's very self seems to be debased denuded of its character by
00:39:01.960 people who see it as a purely predictive exercise and again as i've said before this
00:39:07.880 seems to happen only in physics i mean it's not like the geologists are out there only concerned
00:39:12.440 about predicting what minerals are where what rocks are where they want to understand why
00:39:18.280 they're there in the first place astrophysicists want to understand why it is that galaxies have
00:39:23.720 the shapes that they do why it is in cosmology the universe is behaving the way that it is
00:39:29.800 whether it's going to expand forever and be accelerating right or what's going to happen in the
00:39:33.800 future and why what is the nature of this dark energy not that it's just there and it's causing
00:39:39.000 this particular phenomena and that particular phenomena allows us to make a prediction the prediction
00:39:43.320 is only a small part of what we're really interested in science we're interested in in understanding
00:39:49.800 reality which requires good hard to vary explanations and that's all here another way of putting
00:39:55.880 that is of course it's about problem solving okay so that's where i'll end it today thank you so
00:40:01.400 all of my supporters if you'd like to join them in supporting the podcast then look up patreon
00:40:08.520 talkcast we'll go to breadhall.org where there is a donate button now i'll just leave you
00:40:15.880 before i say goodbye with a final quote from David Deutsch about the centrality of problems not
00:40:22.840 merely to science but to the entire project of knowledge creation and the search for good explanations
00:40:30.680 until next time bye bye and with problems that we are not aware of yet the ability to put right
00:40:37.960 not the sheer good luck of avoiding indefinitely is our only hope not just of solving problems but
00:40:44.840 of survival so take two stone tablets and carve on them on one of them carve problems are
00:40:57.480 soluble and on the other one carve problems are inevitable thank you
