00:00:00.000 All knowledge is conjectural. It could possibly be false. We, after all, are
00:00:06.000 fallible human beings, flawed and prone to error. Moreover, the laws of physics
00:00:10.720 mandate that we cannot possibly have knowledge of all possible factors that
00:00:14.640 might come to bear on any situation. Now, this is a consequence of quantum
00:00:18.400 theory. And also, things decay. A consequence of the second or third dynamics.
00:00:23.840 So our knowledge is necessarily incomplete and subject to errors
00:00:27.760 creeping in over time. So the laws of physics themselves constrain what it is
00:00:31.840 possible to know and how. There's no royal road to truth,
00:00:35.920 knowledge is hard one. And the method by which it is one is by a critical method.
00:00:40.720 Our guess is about reality, a test it out there in the physical world,
00:00:43.600 subject to scrutiny and experiment, argument, and a collision
00:00:47.120 with natural phenomena. Our buildings instantiate our knowledge of
00:00:51.360 engineering. And when the earth moves in a earthquake, our theories of
00:00:54.880 construction are put through trials. If the building collapses in a
00:00:58.480 way unforeseen, we learn something and we learn it the hard way.
00:01:03.360 Now, knowledge is objective in two senses. First, in the ontological sense.
00:01:08.240 The objects out there have a real existence. They are separate from us and not
00:01:12.000 mere products of our mind. Stars would continue to shine and bird to eat
00:01:16.320 even if no people had ever evolved anywhere in the universe to observe any of it.
00:01:21.200 Knowledge is out there in objects. In the day I have a bird,
00:01:25.120 knowledge exists to build a bird. In our built environment, we in
00:01:29.280 stands here at our knowledge of how matter can be shaped and controlled
00:01:32.640 to bend to our will. So we take silicon and craft it into lenses
00:01:36.800 and metal and form it into cylinders and we place the lenses at just the right
00:01:40.160 distance from each other and we build a telescope. We instantiate the
00:01:44.480 knowledge, literally the laws of physics, the laws of optics,
00:01:48.800 as well as some chemistry, into the physical world, into the telescope.
00:01:53.120 The knowledge is out there in the world, not merely in our own minds.
00:01:58.400 We're all the people who ever learned to build telescopes suddenly lost to us,
00:02:02.320 but not the telescopes. All the knowledge of how to build a telescope
00:02:06.640 would not be lost. An interested child coming across such a device,
00:02:11.360 this metal cylinder with a few bits of shaped glass and perhaps some
00:02:14.480 mirrors inside, could find that it could bring into focus distant objects
00:02:18.960 when correctly aligned and fitted with a bit. And with more investigation
00:02:24.720 determined that the lenses have special shapes and they're a careful
00:02:29.680 distance apart from each other and that the cylinder itself serves a special
00:02:32.960 purpose and so on. In other words, almost all the knowledge to build
00:02:41.200 Now I'm going to be reading in part of that from this book,
00:02:46.240 Objective Knowledge by Karl Popper, an evolutionary approach.
00:02:51.280 And the reason I'm doing this is there's been a few
00:02:55.520 interesting internet phenomena that have been going on lately
00:02:59.840 and I think it's probably useful to analyze those in light of what Popper has said.
00:03:06.480 Now return to my telescope. Sure, there's going to be matters of geology if the
00:03:11.440 child wanted to start from absolute scratch and get in the
00:03:13.920 silicon and metal from their oars and perhaps there is some
00:03:17.280 in explicit knowledge as well in the building of the telescope that might make
00:03:22.480 practice, anyone is really curious and a came across a telescope
00:03:25.440 could learn to build a telescope. Even if there was no one else alive who knew
00:03:29.920 what was interested in doing so. And this is ignoring that
00:03:32.960 anyone so interested would have access to libraries in the internet
00:03:35.680 know the resources ever accumulate on telescope building.
00:03:43.360 So this Labor Point is just a sign. Knowledge is out there in objects.
00:03:46.400 It is objective in that sense. Subjectivity exists. That is our
00:03:50.400 experience of the world, a synonym for that poorly understood concept of
00:03:53.760 consciousness. But knowledge insofar as it is there at all
00:03:58.640 is not over the same time. We shall come to that momentary.
00:04:06.880 I'm just saying that knowledge is out there in objects. It is objective in
00:04:10.480 that sense. Now our personal subjectivity of course exists.
00:04:14.480 We have an experience of the world, our experience of the world,
00:04:17.840 our subjectivity. That's just a synonym for that
00:04:20.720 poorly understood concept that we call consciousness.
00:04:24.720 And so subjective knowledge insofar as it exists at all
00:04:29.200 is not at the same type as objective knowledge and will come to that
00:04:32.400 momentarily. But there's another sense in which
00:04:36.320 knowledge is objective. Knowledge is tested by a critical method.
00:04:40.560 When someone makes a claim, there are tests, there are criticisms, there are
00:04:43.760 criteria against which we judged on the knowledge claim.
00:04:47.600 The test can be more or less rigorous, but valid critical tests are not
00:04:51.920 me matters of opinion but rather encounters with reality
00:04:56.320 and other knowledge already out there. So a scientist
00:05:00.080 who claims that they have determined a way, let's say, for humans to travel
00:05:05.600 well we can test this claim. Indeed we can try to build
00:05:10.480 their device or implement their theory and therefore try and
00:05:14.480 refute the claim that way. We often don't need to do this however.
00:05:19.040 But if the test did show the claim to be false, well so much for the claim,
00:05:24.320 often what we do is we just put that claim alongside the best
00:05:28.480 alternatives which for now is Einstein's theory of special relativity.
00:05:31.840 We could use the general theory but I don't think we need to get more
00:05:34.320 complicated and necessary. Now that theory, the special theory explains what
00:05:38.640 happens as your speed increases to near the speed of light.
00:05:42.720 It actually is applicable for all speeds but the phenomena that are
00:05:47.120 unusual are most obvious when you get to the highest speeds.
00:05:51.840 When you do start to get near to the speed of light, time outside of the moving
00:05:55.680 frame slows down with respect to time for the person who's moving.
00:05:59.360 So you're zipping along near the speed of light and you look outside of the
00:06:02.640 frame which you are, if it happened to be a rocket ship, you just look
00:06:07.760 that all the processes going on outside the rocket ship,
00:06:10.640 the ticking of clocks, the aging of people and so on, are happening at a
00:06:14.160 rate slower than what is going on inside the rocket.
00:06:17.360 Everything seems normal inside the rocket, everything outside the rocket
00:06:21.120 seems to have slowed down. So time outside of the moving
00:06:25.200 frame slows down with respect to time for the person who's moving.
00:06:28.640 An object moving at the speed of light, like light itself,
00:06:31.520 actually gets places in zero time. Time outside the frame of a
00:06:35.600 photon of light stops. So going faster than this would mean going
00:06:40.160 back in time and that raises all sorts of problems.
00:06:45.200 And those problems that arise will not be solved by this new claim
00:06:50.240 that you can move faster than the speed of light.
00:06:53.440 And so on that basis we can refute the fast and light theory.
00:06:59.120 Moreover, moving a mass like person to the speed of light requires an
00:07:02.640 infinite amount of energy. So that's another criticism of the new claim.
00:07:06.640 So the claim is going to fail any test. It's going to be
00:07:09.600 unable to answer questions about what happens to time and energy,
00:07:12.400 and it is simply going to fare as an exceedingly poor rival
00:07:16.080 to what already exists, the explanatory theory that is the special theory of
00:07:23.680 has been, has caused it to be refuted by an objective set of criteria.
00:07:27.520 It has failed to do what it purported to, and this is
00:07:30.560 no one individuals in your opinion. There's a fact about what has happened in
00:07:34.960 reality with that new claim. This is objectivity
00:07:40.000 in the epistemological sense. It's not a matter of opinion or bias,
00:07:43.520 that would be subjective in the epistemological sense.
00:07:47.280 And who desires knowledge in that sense? Who wants knowledge to just be about
00:07:51.440 opinion and bias? So so much for the misconception of subjective knowledge,
00:07:56.400 but this doesn't entirely rule out subjective knowledge,
00:08:00.240 but we need to be cautious because subjectivity exists, your
00:08:03.920 consciousness exists. We have a mind, we've got an internal life of
00:08:07.520 consciousness, our thoughts and expectations are confined
00:08:10.640 solely to our own minds. So they are in the sense,
00:08:14.160 kind of subjective knowledge, but what is its nature?
00:08:18.560 A proper road on this. And so let me make a few remarks and a few
00:08:26.560 Subjective knowledge will come to see is knowledge that exists solely within a
00:08:29.520 single organism in some way. Suffice to say for now,
00:08:36.080 proper will explain, but rather an unconscious kind. So for example, the knowledge
00:08:40.160 is in DNA. We will see that conscious subject of knowledge
00:08:44.000 does not exist, but it is also important to dwell upon the idea that
00:08:48.080 subjective knowledge of the kind, expanded by many philosophers,
00:08:51.360 is simply a mistake handed down from Plato. And in many ways,
00:08:54.800 uncritically consumed by generations of teachers, academics,
00:08:58.880 scientists and other thinkers. Plato is the one who demanded that knowledge
00:09:04.400 count only as knowledge when it was justified true belief or JTP.
00:09:10.160 Now elsewhere, I do deal with why knowledge cannot be justified,
00:09:13.440 why we should not expect it to be true and why it cannot be
00:09:17.200 about belief. So you can go to my blog post on Seeking Truth,
00:09:21.840 where I tend to criticize all three parts of that
00:09:27.200 platonic ideal of knowledge being justified. It's not justified, true, it's not
00:09:31.600 true, and it's not about belief. But let's for now, just concentrate on the
00:09:38.400 belief part and explore this notion a little bit more,
00:09:41.280 deeply a little bit more broadly, belief it is, if it is anything,
00:09:45.600 is something that people can have or conscious creatures might have,
00:09:49.600 but books and telescopes do not. As we've already seen,
00:09:53.840 objects out there in the real world, from DNA to books to buildings and
00:09:57.680 telescopes instantiate knowledge. DNA instantiates the knowledge of how to build
00:10:03.520 an organism. The DNA doesn't have beliefs. So with the bare minimum,
00:10:08.800 the knowledge there has absolutely nothing more ever to do with the
00:10:11.680 leaf. So we've already ruled out this JTP conception of knowledge,
00:10:19.520 papa is the most underrated philosopher of the 20th century,
00:10:23.520 although in recent years of the rise of some critical rational
00:10:26.000 groups on the internet, which I think is a wonderful search.
00:10:35.120 More positive reminds of being made about papa, but he still dismissed
00:10:38.480 to something like that guy who said that science was about
00:10:41.600 falsification and not confirmation. And that amounted to the very
00:10:45.920 smallest portion of what his overall philosophy was about.
00:10:50.880 Crucial part, a necessary part, but that is certainly not
00:10:54.640 sufficient to provide a good understanding of what his entire
00:10:59.200 worldview was about. He did remarkably more than just
00:11:02.880 falsification. So let us turn now to some of his remarks on the leaf and
00:11:06.560 subjective knowledge, and only comments where I think they might be useful.
00:11:10.560 These quotes are, as I've already said, from this book
00:11:14.480 objective knowledge in evolutionary approach. This is a 1983 edition.
00:11:21.360 Quite what we have to do is start from the fact that object gives scientific
00:11:26.560 knowledge is conjectural, and then look for its analog in the field of
00:11:31.040 subjective knowledge. This analog can be easily identified.
00:11:35.200 It is my thesis that subjective knowledge is part of a highly complex and
00:11:39.280 intricate in healthy organism, astonishingly accurate apparatus of
00:11:43.760 adjustment, and that it works in the mind, like objective knowledge,
00:11:49.040 by the method of trial and elimination of error, or by conjecture,
00:11:53.120 refutation, and self correction, or take correction.
00:12:00.400 Later, quote, I used to take pride in the fact that I am not a belief philosopher.
00:12:07.120 I'm primarily interested in ideas, in theories, and I find it comparatively
00:12:11.920 unimportant whether or not anyone believes them. And I suspect the interest of
00:12:15.760 philosophers in belief arises from that mistaken philosophy which I
00:12:18.960 call inductivism. There are theorists of knowledge and starting from the
00:12:24.800 subjective experiences, they fail to distinguish between
00:12:28.240 objective and subjective knowledge. This leads them to believe in belief,
00:12:32.800 as the genesis of which knowledge is a species.
00:12:36.720 So the proper then goes on to say that this species from which the knowledge
00:12:42.960 can be derived is something like justification or a criteria of truth,
00:12:46.960 such as clarity or distinctness or visacity or sufficient reason.
00:12:50.800 That's what provides the difference between knowledge and belief.
00:12:56.240 And then quote from Papa. This is why, like Ian Foster,
00:13:03.520 Papa then goes on to explain how there are other reasons for being skeptical of
00:13:06.880 belief. He admits there are psychological states that might be called
00:13:10.400 expectations, and there are shades of these where we might expect things in
00:13:14.160 some bright sense. So for example you might have looked at the timetable
00:13:18.240 and the buses due to arrive at 322 and it's 321 right now,
00:13:22.640 and you check your phone and on the phone you can see the buses about to come
00:13:26.880 as well. So you expect that it's 322 there will be the bus in front of you.
00:13:32.480 And so that's a very bright sense in which you really do have this expectation.
00:13:37.600 And then there's this other sense of sort of more dim sense
00:13:41.680 that perhaps you'll get sick at some point, but before you die you'll get
00:13:45.680 some serious illness. So in some sense you don't really want it to happen.
00:13:50.320 And you're not really believing it, but this is expectation that this is
00:13:54.720 what happens to people before they die. They tend to get sick at some point.
00:14:00.080 So you have this gray scale of expectations all the way from.
00:14:04.960 You expect it strongly in some sense through to you.
00:14:09.200 You kind of know it will happen, but it's sort of a distant dim
00:14:18.400 So some things are immediate and pressing the mind strongly and some
00:14:21.040 less so. Papa says these things do not amount to beliefs,
00:14:25.280 but will be taken seriously by someone who takes induction seriously.
00:14:29.840 And of course he does not. On page 71, Papa then flushes out his thoughts on
00:14:35.040 subjective knowledge some more. He speaks about how
00:14:41.760 expectational thing and that this knowledge which exists in the genes of an
00:14:51.040 So this is a refutation of the blank slate people.
00:14:56.080 Much has been made of Stephen Pinker speaking recently writing books
00:15:09.840 All acquired knowledge all learning consists of the modification
00:15:15.360 possibly the rejection of some form of knowledge of disposition
00:15:19.440 which was there previously and in the last instance consists of
00:15:23.920 inborn dispositions. Papa then goes on to say quote from the point of
00:15:30.320 you here rich. We must reject as completely baseless
00:15:34.480 any subjectivist epistemology which proposes to choose as a
00:15:38.800 starting point what appears to it quite unproblematic.
00:15:43.200 That is our direct or immediate observational experiences.
00:15:52.160 Here let us leave Papa for a moment and come to the present day which I'm
00:15:56.880 speaking on May the 18th 2018. The internet has been a buzz in recent
00:16:05.760 I'm going to provide him my favorite. Let you watch the clip.
00:16:09.920 You should watch it at least four times. I'll just play it once for you.
00:16:15.120 So you need to rewind this video clearly or can't find it on YouTube.
00:16:19.760 When you listen to the following audio you need to listen out for
00:16:24.320 four permutations of the following set of words.
00:16:29.600 The first time you listen listen out for the word
00:16:32.800 brain storm. Brainstorm. Then listen out for the word
00:16:43.760 and finally listen for greens. Now almost everyone I've tested on
00:16:56.720 tested this on a tested on scores of people at this point
00:17:00.560 seems to be able to hear all four permutations with more or less
00:17:03.520 effort. Now what does this suggest? Well it shows our observations are
00:17:08.160 theory-laden to use Papa's jargon. Order returned to our present analysis.
00:17:12.560 We have some expectations. These expectations are
00:17:15.440 root something to do with inborn ideas, a genetic wiring that causes our
00:17:19.200 hearing to be sensitive to particular frequencies.
00:17:21.840 We modified those as we learned language. They're now deeply ingrained and so
00:17:26.400 in context as an English speaker we could be primed to hear certain things.
00:17:30.560 We have expectations, theories and those theories
00:17:34.400 affect what is observed. The real world is out there for us to test
00:17:38.480 but the meaning we find is shaped by our interpretations of it.
00:17:43.520 Let me return out of Papa on page 72 where he has just said we can reject this
00:17:47.840 idea that we must begin our creation of knowledge without direct
00:17:51.600 and immediate observational experiences because they are not
00:17:55.120 absolutely reliable as we have just seen. After what did you hear in that
00:17:59.360 audio? What you hear, what you heard depends entirely upon the theory
00:18:03.360 operating your mind at any given moment. You may even hear something else
00:18:07.520 entirely if you try. Papa says on page 73 now, quote,
00:18:12.080 our observations are highly complex and not always reliable.
00:18:15.440 There were astonishingly excellent decodings of the signals that
00:18:18.160 reach us from the environment. They must not therefore be elevated to a
00:18:21.600 starting point in the sense of a standard of truth.
00:18:24.560 Thus what appeared as an apparently pre-subposition-free subject of
00:18:29.840 epistemology or tabular rather as a theory disintegrates completely.
00:18:35.200 In its places we have to erect a theory of knowledge
00:18:38.160 in which the knowing subject, the observer, plays an important but only a very
00:18:42.640 restricted role, end quote. Now his next section in the book
00:18:48.000 is chapter 3 and it's called knowledge in the object it
00:18:51.520 sense and all quote again. The common sense theory of
00:18:56.320 knowledge and with it all or almost all, philosophers until at least
00:19:00.800 belongs Bolzano and Fraga took it to granted that there was only one kind of
00:19:05.360 knowledge. Knowledge possessed by some knowing subject.
00:19:09.760 I will call this kind of knowledge subjective knowledge
00:19:13.200 in spite of the fact that as we shall see genuine or unadulterated
00:19:18.160 or purely subjective conscious knowledge simply
00:19:22.160 does not exist. Subjective knowledge in the unconscious sense
00:19:27.440 of end quote or hand quote. Subjective knowledge in the unconscious sense
00:19:32.240 consists of the dispositions of an organism so for example
00:19:36.080 when you hit brainstorm earlier on your sensation of this is
00:19:40.720 subjective it can't be shared but you know you heard it right
00:19:46.720 and yet you can also be mistaken about what you heard because a moment later
00:19:50.480 and you hear the same thing but it's green needle
00:19:54.560 so you can be mistaken about your own collier. There's an unconscious
00:19:59.120 dimension to this consciously you can tell yourself okay
00:20:02.240 listen for brainstorm and you'll hear brainstorm
00:20:06.160 you consciously tell your unconscious to do your bidding in this way.
00:20:10.480 Objective knowledge is out there in the real world.
00:20:13.280 Objective knowledge is published in books and instantiated objects like
00:20:16.560 cars and technology it is the kind of thing that can be transmitted
00:20:21.920 but your personal knowledge of the brainstorm team
00:20:25.040 not quite. It's what's called jolly. The subjective character
00:20:30.480 of different perceptions. Beginning on page 106
00:20:36.000 Papa has a chapter titled Epistemology Without Knowing Subjects.
00:20:40.800 Here Papa defends a conception of reality where
00:20:43.920 one we can consider the existence of objects out there in the physical world
00:20:49.440 two we can consider our own mental states and finally
00:20:59.280 which I would say are the explanations published in books and so on that
00:21:03.360 articulate the connection between things. Now this
00:21:07.600 world three is at sometimes called what I'm going to
00:21:10.480 refer to the world but this third kind of structure
00:21:15.200 knowledge objective knowledge is the domain not only of science
00:21:19.120 but also mathematics and art and poetry. It is things apart from just our
00:21:24.560 conscious experience of them. Things that have an existence
00:21:28.720 but they are more than the mere matter in which they appear
00:21:36.160 or life and pixels on a computer screen or sound waves in the air when someone
00:21:40.080 recites the poem or movement of electrons in a while and somewhere
00:21:43.440 amplifies transmits and records it. The poem has an
00:21:47.120 existence that is simply not reducible to its physical
00:21:54.320 but the poem itself is identical no matter what the instantiation is
00:22:02.720 third kind of thing and not about the second kind of thing
00:22:06.160 the mental objects thing so you've got physical objects
00:22:10.400 out there in the real world mental objects inside of your mind.
00:22:14.320 But the third kind of thing knowledge which is the relationship between
00:22:20.480 it hasn't had much to do with number two it doesn't have much to do with
00:22:24.800 mental events going on inside of your mind. Mental states experiences
00:22:29.600 consciousness they're real just as real as one the physical world
00:22:35.600 but in a very analogous way in which knowledge cannot be found
00:22:39.440 in the physical world as nothing but atoms and particles of vibrations
00:22:44.240 in instead has an abstract nature it's a pattern in those things
00:22:48.480 but not reducible to forces laws of motion in physics or motion of particles
00:22:54.560 it cannot be found solely in mental experience either
00:22:59.520 in short it is neither pure matter or pure mental
00:23:03.840 and indeed looking in either of those places exclusively and attempting to
00:23:07.360 reduce knowledge to the mental or to the material
00:23:10.880 is a mistake. In both cases physical objects and mental experiences
00:23:16.880 we find crucial components for the creation representation and use of
00:23:23.840 upon which we record our knowledge and also it is the raw material
00:23:28.800 and also the raw materials in which we instantiate our knowledge.
00:23:33.600 The city grows in the rocks and forests and resources that we gather together
00:23:37.680 but it only happens in the presence of the right knowledge
00:23:41.040 and the mental world of our experience the consciousness of people
00:23:45.120 is where the knowledge is experienced and used to solve problems
00:23:49.760 both your personal problems and problems broadly.
00:23:53.200 Now somebody asked me recently why a subjectivity
00:23:56.400 considered risk to a knowledge? What assumptions underline that claim?
00:24:02.640 Well how and also they asked how and in what ways the subjectivity
00:24:07.600 impact knowledge acquisition and name some areas of knowledge where
00:24:12.240 this is relevant. Okay so here's my answer to that.
00:24:16.320 Subjectivity isn't a risk to knowledge. Knowledge after all
00:24:19.440 is objective so it's kind of impervious to what's going on inside of someone's
00:24:23.840 personal subjectivity but the claim or rather the demand that knowledge be
00:24:28.560 considered as subjective is dangerous because it leads to
00:24:35.360 subjective knowledge is just your opinion. So if knowledge
00:24:38.560 is like that then our attempts to converge upon the truth will fail
00:24:42.480 will all just be going our own way and with no criteria for making progress
00:24:47.440 and sorting what is true from what is false what is good from what is evil
00:24:53.840 There is a harmless way in which there is a species of knowledge which is
00:24:57.200 subjective. All organisms have their own individual DNA so your DNA is
00:25:02.160 different to mine and everyone else is on the planet and all of ours is
00:25:05.680 different to cats and that's different to what a fish has.
00:25:08.800 This genetic knowledge provides us with our experience of the world. For example
00:25:12.800 I can look outside right now and I can see a clear blue sky
00:25:17.440 and the color that I see depends upon the concentration operation of
00:25:21.200 cells called cones and rods in the retina of my eye.
00:25:24.560 This concentration of cones that I have determines the
00:25:28.560 vibrancy of the color that I might see. I might for example have
00:25:33.520 6,234,454 cones and that has been pre-determined by
00:25:39.280 the DNA, the genes that are inside the nucleus of each of my cells.
00:25:46.160 Now you might have not 6,234 cones. You might have
00:25:51.120 6,984,56 cones and in both cases it's to do with our DNA.
00:25:58.000 This is what we are born with in larger parts of
00:26:01.360 doing that DNA, modular mutations that happen throughout the course of our
00:26:05.040 life or whatever. So you know you see a certain color blue when you see
00:26:10.720 the sky. But mine might be ever so slightly different because the
00:26:14.320 cells that are sensitive to color, well we've got a different number of them,
00:26:18.000 a different concentration of them. Maybe there are
00:26:20.160 arranged in the retina slightly differently. All of this gives our
00:26:23.760 perception of a visual perception of the world a slightly different
00:26:26.800 character. Hence also the way in which we hear that
00:26:30.800 brain storm green needle thing. Our ears will also be different because
00:26:36.640 the number of sillier the little sensitive hair cells that are inside the
00:26:39.840 cochlear of our ears, they might be slightly different.
00:26:43.920 So Papa dealt with our subjectivity impacts knowledge acquisition.
00:26:47.280 He said all acquired knowledge, all learning consists of the modification
00:26:51.280 possibly the rejection of some form of knowledge of disposition,
00:26:55.520 which was there previously. And in the last instance of our inborn
00:26:58.880 dispositions end quote. So we start with some inborn ideas
00:27:05.040 and then we adapt these over time as we learn more and more
00:27:08.480 that this happens in our conscious mind as the subjective component. But of
00:27:11.520 course the actual learning is an encounter with the real world.
00:27:14.880 The physical world kicks back and our ideas are sometimes refuted
00:27:19.200 and by that means we learn. But that encounter with the real physical world
00:27:23.200 of objects out there is an objective process. It's not your
00:27:26.640 mere opinion that it turned out when you were making toast this morning and
00:27:30.160 thought you'd leave it on for five minutes. That when it came out
00:27:33.840 black and burn and charred, well that's not your mere opinion.
00:27:38.000 You learn that five minutes is too long to leave bread on to toast.
00:27:42.960 Acquisition learning of this kind is subtly different to that which goes on in
00:27:46.960 let's say silence. Although acquisition begins in a
00:27:52.640 mind subjectively of course and so science in a sense begins in the
00:27:56.800 mind of the scientists with a creative conjecture.
00:28:00.480 But then it's subject to robust criticism from other people
00:28:05.200 and from the world. And then it's no longer a matter of personal
00:28:10.000 subjective experience. It is objective. And it is only
00:28:14.720 objective knowledge through its encounters with the real world.
00:28:17.920 The kicking back from things outside of our mind,
00:28:20.640 that knowledge can improve. I cannot improve my knowledge of the
00:28:24.640 color of the sky by simply staring more and more at it
00:28:28.400 and reflecting in introspecting. That subjective experience is just a
00:28:36.800 isn't something that I have control of in that sense.
00:28:40.880 I can be mistaken about my subjectivity of course,
00:28:44.000 but it is within. If I want to improve it I'll need to communicate with others
00:28:51.440 qualia sensations of blue, for example, cannot be communicated between people.
00:28:56.960 But this is no great obstacle for most of the questions that occupy us for now.
00:29:01.360 David Deutsch, following Karl Popper, has emphasized how
00:29:04.880 objective knowledge is what allows progress and progress that is
00:29:09.120 unbounded. This growth of knowledge has nothing to do with belief,
00:29:13.280 thinking that something is actually true or somehow guessing that something is
00:29:17.040 likely to be the case. No, none of that is required.
00:29:21.440 Knowledge always remains provisional, even though it is objective.
00:29:25.600 Indeed, because it is objective, it can always be subject to error and
00:29:28.960 correction and thus able to be improved. Popper
00:29:32.960 Deutsch really had given us an optimistic vision of how knowledge grows.
