Episode 124: Popper’s Evolutionary Theory of Knowledge

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Unofficial, reviewed transcript. It may still contain mistakes; check the podcast when wording matters.

Speakers are labeled by first name where identified. Unidentified-speaker labels may refer to different people. Bracketed question marks indicate uncertain wording.

Transcript

[00:00:00]  Peter: This week on The Theory of Anything podcast, Bruce continues his exploration of evolutionary epistemology, or the idea that knowledge creation in human minds is analogous to natural selection. Specifically, Bruce discusses how Karl Popper's critical rationalism is and is not related to Donald Campbell's concept of evolutionary epistemology, which it seems Popper mostly endorsed. But is Popper's conjecture and refutation really the same as Campbell's blind variation and selective retention? I enjoyed listening to Bruce in this somewhat shorter episode, and I hope someone else out there does too.

[00:00:49]  Bruce: Welcome to The Theory of Anything podcast.

[00:00:51]  Unidentified speaker: Hey, Peter.

[00:00:52]  Unidentified speaker: Hello, Bruce.

[00:00:53]  Unidentified speaker: How are you doing today?

[00:00:54]  Unidentified speaker: Doing well.

[00:00:55]  Bruce: Today, we're gonna talk about Karl Popper's Evolutionary Epistemology, or that's really not the right term for it. It's gonna be Karl Popper's Theory of, Evolutionary Theory of Knowledge, was what he prefers to call it.

[00:01:09]  Unidentified speaker: Okay.

[00:01:10]  Unidentified speaker: But those are the same thing.

[00:01:12]  Unidentified speaker: Sounds kind of similar, but okay.

[00:01:15]  Bruce: So in episode 114, we talked about Donald Campbell's Evolutionary Epistemology. And we found that most of Campbell's Epistemology actually came from Popper first, by Campbell's own admission. Moreover, Popper said he strongly agreed with Campbell. I read the first part of the first couple paragraphs of Popper's response to Campbell, where he gives a glowing response to Campbell. So I thought we would do an episode where we look at what Karl Popper actually said about what Campbell later called Evolutionary Epistemology. A lot of it written before Campbell and then some of it written after Campbell. I'll try to make somewhat of a distinction. Campbell wrote about it over the course of 20 years, so there's no clear period of before and after Campbell. But Campbell does a lot of quoting of Popper, so we know all that must have come before. Then there's a bunch that Popper does near the end of his life that would have been after Campbell. We're going to quote some of that too. Now, recall that Campbell coined the term Evolutionary Epistemology, but that Popper did not like it. Popper preferred the term Evolutionary Theory of Knowledge. I'll actually give you the quote here when he talks about that. Responding to Campbell's term Evolutionary Epistemology, Popper later says, in a talk entitled Towards a Theory of Evolutionary Epistemology, so he titled his talk Towards a Theory of Evolutionary Epistemology, just to be clear.

[00:02:49]  Bruce: In that talk, Popper says, I now feel that Evolutionary Epistemology, that's in quotes, it's a term, sounds pretentious, especially since there exists a less pretentious equivalent. So please let me change the title of my talk to its equivalent, and let me call this inaugural address Towards an Evolutionary Theory of Knowledge. That's all from All Life is Problem Solving, page 57.

[00:03:14]  Peter: Did you say this is the 70s we're talking about?

[00:03:17]  Bruce: No, no, All Life is Problem Solving, I guess I should have looked up, that was like a later book. I think that was his last book.

[00:03:24]  Peter: Yeah, yeah, yeah, that's right, so 90s basically.

[00:03:27]  Bruce: And then on page 49 of the same book, All Life is Problem Solving, he says, this is a different talk, he says, what others have called my evolutionary epistemology, I have pointed out before that I did not apply that term to my theory of knowledge. It was others who described my theory of knowledge as evolutionary. So for this reason, throughout this podcast, I'm going to call this Popper's Evolutionary Theory of Knowledge in respect to what he wanted to call it. But let me be very blunt here, it's exactly the same as saying Popper's Evolutionary Epistemology. And honestly, the modern term is evolutionary epistemology. And so I don't know why he thought it was pretentious, I have no idea why he thought it was. One thing I would note is that he uses the word towards such a theory, which I think clearly does mean that he doesn't feel we have a full-fledged theory yet. Finally, we're going to discuss what Popper disagreed with Campbell over, which as we'll see wasn't very much.

[00:04:28]  Unidentified speaker: May I interject?

[00:04:30]  Unidentified speaker: At least according to ChatGPT,

[00:04:32]  Peter: which sounds pretty accurate here, that there was a foundation built on this idea in conjectures and refutations and the logic of scientific discovery in the thirties through sixties. But this says that the explicit Evolutionary Epistemology was not used by anyone, including Popper, until 1970s, 70s, basically.

[00:05:05]  Bruce: That would be Campbell's paper where he coins the term, the one we covered in Episode 114.

[00:05:10]  Peter: And it sounds like towards the Theory of Evolutionary Epistemology is around 74 to 76.

[00:05:19]  Bruce: Okay, so that would be soon after or maybe that isn't after. That might be right at the same time.

[00:05:26]  Unidentified speaker: Okay, interesting.

[00:05:27]  Peter: Okay, yeah, here it says 74.

[00:05:30]  Bruce: I mean, I guess it would have to come after when Campbell coined the term. He can't have used the term before it was coined or he would have coined it.

[00:05:39]  Unidentified speaker: So, okay, yeah, okay.

[00:05:42]  Bruce: So a quick review of Campbell's version of Evolutionary Epistemology. So this is from page 56 of Evolutionary Epistemology, Rationality and Sociology of Knowledge, as we covered in episode 114. So quote, a blind variation and selective retention process is fundamental to all inductive achievement, to all genuine increases in knowledge, to all increases in fit of system to environment. So this will become important later when we're attempting to fit this first point. When we're attempting to fit Campbell's Evolutionary Epistemology into modern machine learning. Since no one that I know of would deny machine learning is a legitimate inductive achievement of generalization from observations and an example of fit to system, fit of system to environment. So machine learning offers us a potential counter example or corroboration to Campbell's Evolutionary Epistemology that Campbell could not and Popper could not have known about. Number two, in such a process, there are three essentials.

[00:06:42]  Unidentified speaker: a.

[00:06:42]  Bruce: Mechanisms for introducing variation b. Consistent selection processes c. Mechanisms for preserving and or propagating selected variations. Number three, this is still all quoting Campbell. The many processes which shortcut a more full-blind variation and selective retention process are in themselves inductive achievements, containing wisdom about the environment, achieved originally by blind variation and selective retention. This is Campbell's idea of a hierarchy of blind variation and selective retention processes. Number four, in addition, such shortcut processes contain in their own operation a blind variation and selective retention process at some level, substituting for overt locomotor exploration, or the life-and-death winnowing of organic evolution. Okay, that's the summary. That's Campbell's own summary of his evolutionary epistemology. Keep that in mind now as we talk about Popper's early views that influenced Campbell, which is what we're going to… I'm going to now quote Popper on. So let's begin with Popper's view on epistemology itself, which he says is specifically about the problem of, quote, growth of knowledge. So this is Popper in Logic of Scientific Discovery in the Introduction, so page XIX. The central problem of epistemology has always been and still is the problem of the growth of knowledge. And the growth of knowledge can be studied best by studying the growth of scientific knowledge. For the most important way in which common sense knowledge grows is precisely by turning into scientific knowledge.

[00:08:28]  Bruce: Moreover, it seems clear that the growth of scientific knowledge is the most important and interesting case of the growth of knowledge. Popper adds that it is easier to study scientific knowledge rather than common sense knowledge. Quote, but all past philosophers discovered that scientific knowledge can be more easily studied than common sense knowledge.

[00:08:50]  Unidentified speaker: That's from page XXV.

[00:08:52]  Bruce: So, let's be clear, to Popper, epistemology is specifically about understanding how knowledge grows. And his study into scientific knowledge, his scientific epistemology, which is what he's most famous for, was simply in his mind an attempt to study that because it was the most clear cut and interesting case of the growth of knowledge. But he was actually interested in the concept of the growth of knowledge in general. Now, why am I emphasizing this? If you heard the previous podcast to this one, one of the things I made a very big deal about was when looking at Deutsch's, or maybe we say pseudo-Deutsch theory of knowledge, there was this idea that somehow a genetic algorithm does variation selection, does find some sort of adaption that allows the robot to walk, and yet somehow isn't a growth of knowledge. Okay, and so I'm emphasizing this to really drive home the point that to Popper that's just doesn't make any sense.

[00:09:55]  Unidentified speaker: It's just a contradiction.

[00:09:56]  Bruce: Epistemology is, that process is the growth of knowledge. Okay, so this is at odds with the Deutsch view, where some kinds of variation selection or trial and error processes find solutions to problems like the walking robot example, but aren't to be considered knowledge. To Popper, it was all considered knowledge. So we know Popper would have rejected Deutsch's two sources hypothesis based on this. So Popper never saw his epistemology as explicitly about science, and in fact, he thought there was only a single epistemology, even for fields outside what we'd normally think of as science. So from Logic of Scientific Discovery, page XIX, he says, and yet I am quite ready to admit that there is a method which might be described as the one method of philosophy, that's in quotes. That's like quotes within the quotes. But it is not characteristic of philosophy alone. It is rather the one method of all rational discussion, and therefore of the natural sciences as well as of philosophy. The method I have in mind is that of stating one's problems clearly, and of examining its various proposed solutions critically. Notice how this ties into our episode on rational fallacies, including not merely the idea that we criticize our theories, but that we choose to formulate our theories such, meaning sharply or explicitly, that they can be easily criticized. This is what Popper was saying all along. Okay, but what about animal learning? So David Deutsch has argued that all an animal's knowledge is in its genes, and by implication that animal learning is not a growth of knowledge.

[00:11:40]  Bruce: This is a necessary implication of Deutsch's two-sources hypothesis. So of course, that's why he puts this forward. So Deutsch even goes so far as to claim that animal memes, which he admits really do exist, are somehow actually knowledge in the animal's genes, even though the term meme is generally understood to tautologically be a kind of culture of knowledge outside of the genome.

[00:12:04]  Unidentified speaker: Okay.

[00:12:05]  Bruce: So famously, Donald Campbell, episode 114, strongly disagreed with Deutsch on this. Campbell took the idea that animal learning was a kind of evolutionary epistemology, rather than induction, from Popper himself. Here is one such Popper quote that Campbell used. Conjecture and Refutation, page 292. Although I shall confine my discussion to the growth of knowledge in science, my remarks are applicable without much change, I believe, to the growth of pre-scientific knowledge also. That is to say, to the general way in which men, and even animals, acquire new factual knowledge about the world. The method of, and this is, the method of learning by trial and error, of learning from our mistakes, seems to be fundamentally the same, whether it is practiced by lower or by higher animals, by chimpanzees or by men of science. So notice how Popper is agreeing with Campbell here, not Deutsch. Popper again emphasizes that this study of science was really to simply understand the broader idea of the growth of knowledge. Quote, my interest is not merely in the theory of scientific knowledge, but rather in the theory of knowledge in general. Yet the study of the growth of scientific knowledge is, I believe, the most fruitful way of studying the growth of knowledge in general. For the growth of scientific knowledge may be said to be the growth of ordinary human knowledge writ large.

[00:13:31]  Bruce: Note how between these two quotes, there should be no doubt that Popper did see animal learning as a kind of growth of knowledge, typical of this more general epistemology of trial and error learning that Campbell called evolutionary epistemology. Thus, we know for sure that Popper would not have agreed with David Deutsch that all of an animal's knowledge was in its genes. Now, I suspect some Deutschian crit rats will try to argue with me here, that actually that last quote was meant only that animals learn by dying. So, we're talking about biological evolution.

[00:14:05]  Unidentified speaker: Okay.

[00:14:06]  Bruce: I don't read it that way, and I think that's a stretch. But let's, for the sake of argument, assume that that's maybe a possibility. Let's see if we can get a more clear-cut quote here. So, in fact, there are quotes from Popper. We just partially quoted one of them, where he claims that Einstein can learn in his lifetime by criticizing his own theories, whereas amoeba has to die for the species to learn. So there are quotes you can find of Popper, where he is talking about animals dying. But he doesn't always talk about it that way. So if you are in doubt that Popper did agree with Campbell, that animal learning is a kind of evolutionary epistemology, and that knowledge growth, here is a far, here is a far clearer example of Popper stating this. So this is now from Realism and the Aim of Science, one of his later books, page 97. Dispositional preparedness, so think about how genes give you expectations and so you have some sort of disposition towards something.

[00:14:59]  Unidentified speaker: That's what he's talking about here.

[00:15:01]  Bruce: Dispositional preparedness for what is to come seems to be the true biological analog of scientific knowledge. In an animal organism, disposition to react in a certain manner to certain kinds of stimuli are partly inborn, in other words, partly genetic. My thesis is that, so far as these dispositions are acquired in the lifetime of the animal, they are modifications of inborn dispositions, which are plastic and which develop and change upon being activated by stimuli and especially also under the influence of failure and success, coupled perhaps with painful and pleasurable feelings. He's talking about classical conditioning and operant conditioning here. In this way, the organism develops its inborn dispositional knowledge, the genetic knowledge, and it learns by trial and error. So that was all page 97. Hopefully, this puts to rest the idea that Popper would have ever agreed with Deutsch that all of an animal's knowledge is in its genes. That whole position just is inconsistent with Popper's Theory of Evolutionary Knowledge. Now, let's consider Popper's view on induction. This is from Conjecture and Refutation, page 60. Hume, having cast out the logical theory of induction by reputation, he struck a bargain with common sense, merely allowing the re-entry of induction by repetition, in the guise of a philosophical fact. So Popper here is referring to the fact that Hume, despite his criticism of induction, accepted induction still, as real and correct, just unjustified or worse, irrational.

[00:16:39]  Bruce: As we discussed in episode 116, when covering Strevens' The Knowledge Machine, Hume's attitude was that humans did use induction to create knowledge, it was just irrational to do so. But don't worry, Hume's view was, don't worry about that, it's just how things are, move on with your life. At least that's the way Strevens presents him. Popper basically is presenting him in the same way here. Continuing the Popper quote, I propose to turn the tables on this theory of Hume's. Instead of explaining our propensity to expect regularities as the result of repetition, I propose to explain repetition for us as the result of our propensity to expect regularities and to search for them. Thus, I was led by purely logical consideration to replace the psychological theory of induction by the following view. Without, and here's the view now, without waiting passively for repetitions to impress or impose regularities upon us, we actively try to impose regularities upon the world.

[00:17:38]  Unidentified speaker: That is to say, we come up with a hypothesis to explain the observations.

[00:17:42]  Bruce: And now, going back to quoting Popper, we try to discover similarities in it, in the world, and to interpret it in terms of laws invented by us. Without waiting for premises, we jump to conclusions. These may have to be discarded later should observations show that they are wrong. This was a theory of trial and error, this is still quoting Popper, this was a theory of trial and error of conjecture and refutation. It made it possible to understand why our attempt to force interpretations upon the world were logically prior to the observations of similarities. Is Popper talking about science specifically here? No. He goes on to clarify that he sees science as just one example of this. Quote, since there were logical reasons behind this procedure, I thought that it would apply to the field of science also. Campbell here adds, quote, Popper has effectively rejected the model of passive induction even for animal learning, and advocates that here too the typical process involves broad generalizations from single specific initial experiences, generalizations which subsequent experience edits. That's from page 50 of the other book, the Evolutionary Epistemology book that I mentioned. Again, we need to call out machine learning here. Can Popper's view that induction by repetition requires prior theories that are tested be squared with actual modern machine learning? If so, then machine learning is actually a kind of evolutionary epistemology. Or does modern machine learning offer us a counter example and thereby refute Popper's expressed view?

[00:19:19]  Bruce: Now, you may want to check out my episode number 91 with the clickbait title, The Critical Rationalist's Case for Induction, for a tentative first answer to this question. But as far back as episode 26, I've argued that this is a more difficult problem than it first appears. And that there are some interesting potential counter examples that are hard to explain within the way Popper and Campbell see this. That being said, Popper then saw trial and error as the universally rational way to adopt, to adapt to the world. So from page 68 of Conjecture and Refutation, Popper says, If we have made this our task, that is to adapt to the world we live in, then there is no more rational procedure than the method of trial and error, of conjecture and refutation, of boldly proposing theories, of trying our best to show that these are erroneous, and of accepting them tentatively if our critical efforts are unsuccessful. Continuing the quote, From the point of view here developed, all laws, all theories remain essentially tentative, or conjectural, or hypothetical, even when we feel unable to doubt them any longer. Before a theory has been refuted, we can never know in what way it may have to be modified. That quote claims trial and error is the most rational. But in fact, Popper elsewhere makes it clear he really meant it's the sole way knowledge can ever grow. Quote, this is quoting Popper now, When discussing how to move from observation statements to a good theory, i.e.

[00:21:00]  Bruce: how to induce things from observation statements, the answer is, quote, by jumping first to any theory and then testing it to find whether it is good or not.

[00:21:13]  Unidentified speaker: i.e.

[00:21:13]  Bruce: by repeatedly applying the critical method, eliminating many bad theories and inventing many new ones. There is no other way.

[00:21:21]  Unidentified speaker: End of quote.

[00:21:23]  Bruce: So Popper is arguing there is only one kind of true kind of quote unquote induction, and that is the induction in this case, meaning just moving from observation statement to general theory. And that is his epistemology of trial and error of conjecture refutation. This is why Popper claims that you can refer to his epistemology of critical discussion as induction if you wish. Quote, this is from Myth of the Framework. So I may say now that I do not believe there is such a thing as an inductive method or an inductive procedure, unless indeed you decide to use the name induction for that method of critical discussion and of attempted refutations which I have discussed here. And then he goes on to say, I never quarrel about words and I have of course no serious objection if you wish to call the method of critical discussion induction. But if you do, then you should be aware of the fact that it is very different from anything that has ever been called induction in the past. Popper is claiming this is the sole and only way to induce anything and by extension the sole way of knowledge to grow. Note here that Popper is clearly equating what Campbell called inductive achievement with growth of knowledge. Those are to Popper and to Campbell one and the same thing. So when Campbell argued in Episode 114 that all inductive achievement was actually evolutionary epistemology, Campbell was getting this from Popper. I raised this in preparation for a future podcast in which I will discuss my disagreements with Ella Hoeppner over how to best interpret Campbell's theory.

[00:22:57]  Bruce: But we don't need to get into that today. A similar quote from Popper to drive the point home here. While I read this quote, recall in the previous episode where the genetic algorithm that causes the robot to walk from Deutsch's beginning of infinity and the immune system both solve real world problems, yet Deutsch claims that they do not create knowledge. So Popper says, this is from Objective Knowledge, page 142, epistemology from the objectivist's viewpoint becomes the theory of problem-solving, or in other words, of the construction, critical discussion, evaluation and critical testing of competing conjectural theories. Again, I see no way in which you can reconcile this statement with Deutsch's views any more than I see how you can reconcile Deutsch's views to Campbell's epistemology.

[00:23:48]  Unidentified speaker: So let's summarize.

[00:23:49]  Bruce: We've seen that Popper has argued so far, all generalizations from observation may look like induction, but it's really his epistemology of trial and error. Then he equates this to knowledge growth and claims all knowledge growth comes from this same process of trial and error. And we've seen that Popper sees animal learning as one kind of this trial and error epistemology, and that there simply is no other way by which these things can happen, arguing for a single unified epistemology that rejects any sort of induction, unless by induction you mean his epistemology. I'm hoping you're seeing at this point that Popper really was the basis for all of Campbell's Theory of Evolutionary Epistemology. It is probably more accurate to refer to it as Popper's Evolutionary Epistemology rather than Campbell's. I'm doing no injustice to Campbell when I say this. Here is Campbell saying the same thing himself from page 89 of Evolutionary Epistemology. This essay has identified Popper as the modern founder and leading advocate of a natural selection epistemology. The characteristic focus is on the growth of knowledge. The problem of knowledge is so defined that the knowing of other animals than man is included. All right, now, let's take a look at Popper's... He gave a speech, and it became a chapter in his books that's called Of Clouds and Clocks. And it was one of the main basis for Campbell's theory of evolutionary epistemology. And we extensively quoted from it in episode 114. We were quoting Campbell, quoting Popper in this case.

[00:25:31]  Bruce: Let's go directly and quote in full what Popper actually said. That speech was actually Popper's attempt, in my opinion, a failed attempt to refute the philosophy of determinism. Determinism is in fact true, so you can't refute it. But it contains an excellent selection on Popper's views that inspired Campbell's evolutionary epistemology, with Campbell quoting it at length in his article. So I'm going to read that portion of the talk in full. So this is from Objective Knowledge, page 242 plus. I went for a number of pages. Popper says, My theory may be described as an attempt to apply to the whole of evolution, what we learned when we analyze the evolution from animal language to human language. And it consists of a certain view of evolution as a growing, hierarchical system of plastic controls.

[00:26:21]  Unidentified speaker: There are plastic controls.

[00:26:22]  Bruce: There is the hierarchy that Campbell always talks about. And of a certain kind of organism as incorporating in the case of man, evolving exosomatically. This growing, hierarchical system of plastic controls. The Neo-Darwinist Theory of Evolution is assumed, but it is restated by pointing out that its mutations may be interpreted as more or less accidental trial and error gambits, and natural selection is one way of controlling them by error elimination. I shall now state the theory in the form of 12 short theses. Number one, all organisms are constantly day and night engaged in problem-solving. Notice that this is all organisms, not just humans.

[00:27:09]  Bruce: And so are all those evolutionary sequences of organisms. That would be biological evolution. So notice he makes a distinction between animals being problem-solvers and evolution as problem-solvers. The phyla which begin with the most primitive forms and of which the now living organisms are the latest members. Note that Popper sees a unification here between animal learning and biological evolution, but he does not see them as one and the same. Number two, these problems are problems in an objective sense. They can be hypothetically reconstructed by hindsight, as it were. I will say more about this later. Objective problems in this sense need not have their conscious counterpart. And, where they have their conscious counterpart, the conscious problem need not coincide with the objective problem. Number three, problem-solving always proceeds by the method of trial and error. New reactions, new forms, new organs, new modes of behavior, new modes of behavior, animal learning, new hypotheses are tentatively put forward and controlled by error elimination. Again, notice that Popper unifies animal learning and biological evolution. Number four, error elimination may proceed either by the complete elimination of unsuccessful forms, the killing off of the unsuccessful form by natural selection, or by the tentative evolution of controls, which modify or suppress unsuccessful organs or forms of behavior or hypotheses. Notice that Popper is outright saying it.

[00:28:45]  Bruce: Animal learning is a legitimate kind of knowledge creation via evolutionary epistemology, distinct from the biological process, biological evolution, I mean. Number five, the single organism telescopes into one body, as it were. The controls developed during the evolution of its phyla, the biological evolution, just as it partly recapitulates in its ontogenetic development into phylogenetic evolution. Number six, the single organism is a kind of spearhead of the evolutionary sequence of organisms to which it belongs, its phyla. It is itself a tentative solution, problem solving into a new environment, niches, choosing an environment and modifying it. It is thus related to its phyla almost exactly as the actions, behaviors of the individual organism are related to this organism. I don't know how you can get more clear that Popper is saying that not all of an animal's knowledge is in its genes. The individual organism and its behavior are both trials, which may be eliminated by error elimination. Number seven, using P for problem and TS for tentative solution. A lot of people have quoted Popper saying this.

[00:29:56]  Unidentified speaker: This is a great quote.

[00:29:57]  Bruce: And EE for error elimination. We can describe the fundamental evolutionary sequence of events as follows. Problems lead to tentative solutions which lead to error elimination, which lead to a problem. But this sequence is not a cycle. The second problem is in general different from the first. It is the result of a new situation which has arisen in part because of the tentative solution which has been tried out. And the error elimination which controls them. In order to indicate this, the above schema should be rewritten. Problem one, tentative solution one, error elimination. Problem two, eight. But even in this form, an important element is still missing. The multiplicity of tentative solutions, the multiplicity of trials. Thus, our final schema becomes something like this. Problem one, tentative solution one, error elimination. Problem two, and then a number of different tentative solutions to try out. Number nine, in this form, our schema can be compared with that of neo-Darwinism. According to neo-Darwinism, there is in main one problem, the problem of survival. There is, as in our system, a multiplicity of tentative solutions, the variations or mutations. But there is only one way of error elimination, the killing of the organism. And partly for this reason, the fact that problem one and problem two will differ essentially is overlooked, or else its fundamental importance is not sufficiently clearly realized. Number 10. In our system, not all problems are survival problems. Okay, we just said that all the problems of biological evolution are survival problems.

[00:31:25]  Bruce: Now he's saying that in his system, that's not the case. There are many very specific problems and sub-problems, even though the earliest problem may have been sheer survival problems. For example, an early problem P1 may be reproduction. Its solution may lead to a new problem P2, the problem of getting rid of or spreading the offspring. The children which threaten to suffocate, not only the parent organism, but each other, it is perhaps of interest to note that the problem of avoiding suffocation by one's offspring may be one of those problems which was solved by the evolution of multicellular organisms instead of getting rid of one's offspring. One establishes a common economy with various new methods of living together.

[00:32:11]  Unidentified speaker: Number 11.

[00:32:12]  Bruce: The theory here proposed distinguishes between problem 1 and problem 2 and shows that the problems or the problem situation which the organism is trying to deal with are often new and arise themselves as products of evolution. The theory therefore gives implicitly a rational account of what has been called by the somewhat dubious name Creative Evolution or Emergent Evolution. Number 12. Our schema allows for the development of error-eliminating controls, warning examples, warning organisms like the eye, organs like the eye, feedback mechanisms, that is, controls which can eliminate errors without killing the organism. There you go again. Animal learning is a form of knowledge creation to Popper, and it makes it possible ultimately for our hypotheses to die in our stead. Notice that he's talking about animals here, not humans. Each organism can be regarded as a hierarchical system of plastic controls, of a system of clouds controlled by clouds. The controlled system makes trial and error movements, which are partly suppressed and partly restrained by the controlling system. We have already met an example of this in the relation between the lower and higher functions of language. The lower ones continue to exist and play their part, but they are constrained and controlled by the higher ones. Another characteristic example of this, if I am standing quietly without making any movement, then according to the physiologist, my muscles are constantly at work, contracting and relaxing in an almost random fashion.

[00:33:43]  Bruce: See, temporary solutions N to M of Theses 8 of the preceding section, but controlled without my being aware of it by error elimination, so that every little deviation of my posture is almost at once corrected. Notice that this is an example of non-explanatory knowledge creation, that Popper sees something as simple as your body subconsciously moving your muscles to keep you standing upright as a form of his evolutionary epistemology. Nothing at all to do with explanatory knowledge. Okay, so I am kept standing quietly or more or less the same, by more or less the same method, by which an automatic pilot keeps an aircraft steadily on course. Notice that Popper places these subconscious biological processes into the very same evolutionary epistemology as he does everything else. But he also considers an AI, which in this case is the the airplane autopilot, as part of the same evolutionary epistemological framework and as thus relevant to his overall epistemology. Campbell got this all from Popper, right? Like it's all there. This example also, this is back to quoting Popper, this example also illustrates the theses one of the preceding section, that each organism is all of the time engaged in problem solving by trial and error.

[00:35:04]  Unidentified speaker: Animal learning!

[00:35:05]  Bruce: That it reacts to new and old problems by more or less chance like or cloud like trials, which are eliminated if unsuccessful. If unsuccessful, they increase the probability of the survival mutation, which simulate the solution, solution so reached, and tend to—and tend to make the solution hereditary by incorporating it into the spatial structure or form of the new organism. Here he's talking about the Baldwin Effect.

[00:35:34]  Unidentified speaker: Thank you.

[00:35:34]  Bruce: He's referring to the Baldwin Effect here, which we've talked about in past podcasts.

[00:35:39]  Unidentified speaker: Oh, yeah.

[00:35:39]  Bruce: Okay. So, let's then—so that was all prior to—that's the end of that of what Popper said in that. Notice that Campbell really got all of it from Popper. Like it's all there, okay? Now, Popper then does work in evolutionary epistemology or in his theory of evolutionary theory of knowledge after Campbell. So let's actually take a look at that. So after Campbell coined the term evolutionary epistemology and spent 20 years developing it, Popper also tried to develop the same theory. You especially see this in the book All Life is Problem Solving, his final book. I'm going to now quote a few important passages from that book that further clarify and elucidate what we're calling Popper's evolutionary epistemology or his evolutionary theory of knowledge. Popper's main emphasis was different than ours today. He spent a huge amount of time in his effort developing his evolutionary theory of knowledge to refute empiricism, which was, as Popper defined that term, the theory that knowledge comes from our senses. So from page 63 of All of Life's Problem Solving, Popper says, philosophers and even scientists often assume that all our knowledge stems from our senses, the sense data which our senses deliver to us. They believe that the question, how do you know, is in every case equivalent to the question, what are the observations that entitle you to your assertion? But to do this, so that's the end of the quote from Popper. But to do this, Popper had to make a distinction between an animal's genetic knowledge found in its genes and the knowledge created via its ability to learn.

[00:37:09]  Bruce: So quote, page 63, but seen from a biological point of view, this kind of approach is a colossal mistake. For our senses to tell us anything, we must have prior knowledge. Here the prior knowledge is the genetic knowledge. I'm going to pick out a few choice selections from Popper where he makes this point. Thus argues Popper, quote, I assume that it is only genetically a priori and not valid a priori, not a priori necessary, not apodactic, apodectic, I forget how to pronounce that, meaning absolute certain knowledge is what that term means. To put this in another way, we learn only through trial and error.

[00:37:53]  Unidentified speaker: There we go again.

[00:37:54]  Bruce: Our trials, however, are always our hypotheses. They stem from us, not from the external world. All we learn from the external world is that some of our efforts are mistaken.

[00:38:04]  Unidentified speaker: That's page 47.

[00:38:05]  Bruce: So Popper here argues that there is no way to learn other than via his generalized epistemology, that we but not he is calling evolutionary epistemology. Continuing quoting Popper, quote, my starting point is a very simple proposition, indeed an almost trivial one. The proposition that animals can know something, that they can have knowledge. If we stopped here, Deutsch and crit rats would undoubtedly respond, yes, but that knowledge is purely genetic. But Popper continues on the quote, for example, a dog may know his master returns home on working days at about 6 PM. Notice that this is clearly animal learning we're now talking about. A dog does not have a genetic knowledge that his master is going to return home on weekdays at 6 PM. Okay, that is not what Popper is talking about. He is talking about animal learning as actual knowledge that fits his epistemology. And then he continues, and the behavior of the dog may give many indications, clear to his friends, that he, the dog, expects the return of his master at that time. Ah, so Popper is now talking about genetic, not talking about genetic knowledge here. His thesis is actually that animals grow their knowledge via learning. Continuing the quote, page 58 now. I shall show that in spite of this triviality, the proposition that animals can know something, completely revolutionizes the theory of knowledge as it is still widely taught. Quote, continuing same page.

[00:39:36]  Bruce: Now, if you are interested in the theory of evolution, you will find that part of it is the important theory of homology, and that the dog's nose and my nose are homologous. My attribution of knowledge to the dog is therefore an anthropomorphism, but it is not a metaphor. Rather, it implies the hypothesis that some organ of the dog, in this case, presumably the brain, has a function that corresponds not only in some vague sense to the biological function of human knowledge, but is homologous with it.

[00:40:09]  Unidentified speaker: All page 58, continuing on page 59 now.

[00:40:12]  Bruce: The existence of animal knowledge is not a mere metaphor, but a serious evolutionary hypothesis. Popper is arguing that animal learning is knowledge growth. How does this help his argument against empiricism? To understand this, he develops the idea that there are at least two kinds of knowledge relevant here. First, there is a priori knowledge in the genes, that is of a general kind. Second, there is knowledge created in the lifetime of the animal, that is, its learning, that is specific to the animal and to its specific circumstance. Quote, the distinction between adaption to or unconscious knowledge of law-like and long-term environmental conditions, such as gravity and the cycle of changing seasons, on the one side, that's one kind of knowledge, and adaptions to or knowledge of environmental short-term changes in events. On the other side, for example, the dog expecting its master to come home, is of the greatest interest, while short-term events occur in the life of the individual organisms.

[00:41:16]  Unidentified speaker: I'm going to read that again.

[00:41:18]  Bruce: There's just no doubt what Popper's talking about here, guys. While short-term events occur in the life of the individual organisms, that that kind of knowledge occurs in the life of the individual organism. It is not part of the germ line.

[00:41:30]  Unidentified speaker: It's not in the DNA.

[00:41:31]  Bruce: He specifically says it's in the brain. The long-term and law-like environmental conditions are such that adaption to them must have been at work throughout the evolution of countless generations. Notice the distinction there. Short-term knowledge, that's animal learning, created through animal learning. Long-term knowledge, that's the biological genetic evolution that's in the DNA. Continuing the quote, and if we look more closely at short-term adaptions, at the knowledge of and the response to environmental short-term events, then we see that the ability of the individual organisms to respond appropriately to short-term events, such as a particular pull of the wind, or in the animal kingdom, the appearance of a foe, is also a long-term adaption, and also the work of adaption going on through countless generations, because it's dependent upon that genetic knowledge. So Popper argues for two kinds or forms of knowledge, long-term genetic knowledge and short-term knowledge via animal learning. The reason Popper is emphasizing this distinction between an animal's genetic knowledge and their knowledge created via learning is because knowledge created through the senses is the second kind. It's part of animal learning. Popper's point is that you can't have learning knowledge, even through the senses, without first having a priori genetic knowledge that one's built on top of the other. It's the hierarchy that Campbell always talks about. Quote, I hope I have been able to give you some idea of the importance of the distinction between long-term and short-term adaption.

[00:43:00]  Bruce: Long-term and short-term knowledge and the fundamental character of long-term knowledge, of the fact that it must always precede short-term or observational knowledge, and of the impossibility that long-term knowledge can be obtained from short-term knowledge alone.

[00:43:17]  Unidentified speaker: That's page 64.

[00:43:19]  Bruce: Note here how this fits nicely with Campbell's hierarchy of blind variation and selective retention algorithms. Knowledge comes from knowledge. And again, we see there is no way to reconcile Popper's Evolutionary Theory of Knowledge with Deutsch's Two Sources Hypothesis, or with his claim that all of an animal's knowledge is in its genes. Quote, page 51, These forms of knowledge, or these adaptions, especially among animals, may be described as expectations. The dog expects its master at half past five. Animal learning, not biological knowledge. It becomes restless, and one can see it is prepared for its master to come home at half past five. These are forms of knowledge, says Popper. And these forms of knowledge are in every respect expectations.

[00:44:10]  Unidentified speaker: That's all page 51 still.

[00:44:12]  Bruce: Popper explains how animal learning is a type of adaption, not unlike biological evolution. This is from page 47. From primitive forms of life onward, from the earliest cells, adaption is an invention on the part of living creatures. Living creatures adapt and themselves improve their adaptions.

[00:44:31]  Unidentified speaker: Notice again the two kinds of adaption, genetic and learning.

[00:44:36]  Bruce: Popper here is referring to adaptions in animal behavior due to learning, as opposed to genetic knowledge built into genes. He goes on to therefore argue, quote, page 49, life must be adapted to the future conditions of the environment. In this sense, general knowledge, that is, knowledge in the genes, comes earlier than momentary knowledge, than special knowledge, i.e.

[00:44:59]  Unidentified speaker: knowledge created via animal learning.

[00:45:01]  Bruce: Right from the start, we must be in this way equipped with general knowledge, i.e. in the genes, and with the knowledge we usually call knowledge of the laws of nature. [Or?] with the knowledge we usually call knowledge of the laws of nature.

[00:45:16]  Unidentified speaker: Page 49.

[00:45:17]  Bruce: Page 50-51, he says, My position in epistemology goes further than that of all other epistemologists. Whether evolutionary, Kantian, or non-evolutionary, general adaptions precede momentary adaptions. They exist first.

[00:45:32]  Unidentified speaker: They are a priori.

[00:45:35]  Bruce: Popper's point, in context, is that even knowledge gained via the senses requires pre-existing, more general genetic knowledge first. Thus the senses are not a pure source of knowledge, as was then assumed, but require pre-existing theories that could be overridden or refuted, making the more general genetic knowledge itself a conjecture that gets overridden by animal learning. It's doubtful Popper would have ever even conceived that future critical rationalists would doubt that animal learning was a kind of growth of knowledge, and that, quote, all of animals' knowledge was in its genes. But he's trying to argue that what he's trying to argue is that animal learning is explicitly a growth of knowledge consistent with his evolutionary theory of knowledge via trial and error learning. Notice from these next quotes that is specifically what he is getting at. Quote, page 72, All organisms are problem finders and problem solvers. I would argue then that all living things are active, meaning active learners. They are always casting about in every direction like beetles. We feel our way towards things with every means at our disposal. Page 53, we are always know nothings and always trying to find our way with our hands and our feet or our ears and our eyes and with any sense organs we have, which we use actively to make sure of the reality around us. My theory of knowledge is thus quite revolutionary. It overturns everything my predecessors have said up to now. We humans are active. We are constantly testing things out, constantly working with the method of trial and error.

[00:47:07]  Bruce: Page 53, and continuing from there. And that is the only method of knowledge growth we have. We also, the only method we can assume the earliest animals or plants to have had. They move hither and thither. Primitive animals make trial movements and somehow try to optimize something. They seek and they find. Primitive animals are already looking for better surroundings, for better worlds. And they are active in their quest for a better world. Like, how do you possibly reconcile what this is being said with the idea that all of an animal's knowledge is in its genes? It's just impossible. That is not how Popper saw it. Notice that so far Popper is explicitly talking about animal learning being a growth of knowledge consistent with his epistemology and analogous to how humans learn. But he then wants to show that, as his epistemology predicts, this is only possible due to genetic knowledge making it possible since all knowledge growth requires pre-existing theories that you then have to refute. So quote, he says, In this quest, they, the animals, must, as I said, already have somehow adapted, meaning genetically, they must already have some general knowledge. Then comes mutations and further adaption via animal learning. That is the empirical method of trial and error. Quote, quoting Popper, To sum up, from a biological point of view, animals and human knowledge consists in often unconscious expectations or potential expectations.

[00:48:39]  Unidentified speaker: Page 53.

[00:48:40]  Bruce: But I would argue that our knowledge, and this is interesting, it's probably wrong, but this is interesting that he says this. I would argue that our knowledge, meaning human knowledge, is 99% or let us say 99.9% biologically innate. Note here that Popper is arguing that both humans and animals are 99.9% genetic knowledge. But what is the rest of our knowledge, then? Quoting Popper, the rest is a modification, a revolutionary overturning of some previous knowledge, meaning genetic knowledge, just as that knowledge was itself once a revolutionary overturning of something that went before. But in the end, all knowledge, meaning genetic or learning, goes back to innate knowledge and to its modification.

[00:49:22]  Unidentified speaker: Page 54.

[00:49:23]  Bruce: Thus, in Popper's disproof of empiricism, or the idea that knowledge comes directly from the senses, that's his argument in a nutshell. So instead, Popper shows that even learning via our senses is a form of his evolutionary epistemology, just like Campbell made the same argument.

[00:49:41]  Unidentified speaker: So page 115 now.

[00:49:43]  Bruce: Let's now talk about Popper's reaction to Campbell's evolutionary epistemology. So I'm going to quote, I already quoted this first part, but I'm going to give some extensive quoting from Popper's response to Campbell, including where he says he disagrees with Campbell, or where he might have a disagreement with Campbell. So starting the first part of the quote, page 115 of evolutionary epistemology. Okay, here's Popper now responding to Campbell. Professor Campbell's remarkable contribution, Chapter 2 above, shows the greatest agreement with my epistemology and, what he cannot know, an astonishing anticipation of some things which I had not yet published. When he wrote his paper, In addition, it is a treatise of prodigious historical learning. There is scarcely anything in the whole of modern epistemology to compare with it, certainly not in my own work. His historical references are all highly relevant, and they are a real treasure house, and they often surprised me greatly. For me, the most striking thing about Campbell's essay is the almost complete agreement down to even in minute detail between Campbell's views and my own. I shall try to develop one or two of these points a little further, and shall then try to in the very rare and comparatively minor points, turn to the very rare and comparatively minor points, where there may be some difference of opinion. So let's actually go through what he talks about.

[00:51:08]  Bruce: So thanks to Deutsch's Two Sources Hypothesis, the idea that there are only two sources of knowledge, biological evolution in genes and human ideas, there are numerous crit rats today that strongly believe with Campbell's, disagree with Campbell's more ubiquitous view of knowledge growth. The two most important disagreements are that Deutsch and crit rats don't believe AI, machine learning, the immune system or animal knowledge, even animal memes, should count as knowledge creation. As we've seen, Campbell's actually got his ideas from Popper, and Popper doubled down on this view after Campbell published his paper. And how might crit rats explain, or in my opinion, explain away Popper's strong endorsement of Campbell's theories? Now, I would anticipate that they'd claim that Popper agreed with some aspect of Campbell's theory but disagreed with him on others. And I suspect crit rats will be tempted to try to drive a semi-truck through that small loophole, because Popper did say minor disagreements. Unfortunately, Popper seems to have anticipated this problem and already closed the loophole. Popper specifically tells us what he disagrees with Campbell over, which we're going to cover in detail. There are a number of points where Popper feels Campbell doesn't say as much as he'd like, though Popper claims they aren't disagreeing. So for example, page 116, Campbell does not say very much about my theory of World Three, and it is here that I would like to make some remarks in amplification of his.

[00:52:35]  Bruce: Popper then immediately argues that animal learning is a form of knowledge growth for that animal. Quote, a point which follows almost directly from his critical realism is that I have described what is what I have described as the knowledge situation of animals and of men, so far as knowledge is not genetically built into them. Oh, animals and men have knowledge not genetically built into them. Okay, animals and men can only gain knowledge if they have to drive, if they have a drive or instinct for exploration, for finding out more about the world. Whoa, Popper just said it outright. The knowledge situation for both animals and humans is that all their knowledge is that all their knowledge is not genetically built into them. And instead they are given a drive or instinct towards curiosity and exploration to gain additional knowledge not found in their genes. Popper contrasts this with the more then popular idea that knowledge is gained passively through the senses, quote, rather than passive recipients of information impressed upon from the outside, of Lamarckism and inductivism, page 116. Thus, it is an, by the way, I just can't help but say this. Notice that this idea that the animal is just simply learning through its senses and there's no knowledge being gained through trial and error, that he just sees that as Lamarckism or inductivism. Okay, so in essence, the crit rat view is a form of Lamarckism, inductivism from Popper's viewpoint.

[00:54:12]  Bruce: Thus, it is an almost immediate consequence of critical realism, together with an evolutionary approach, to regard ourselves and our knowledge as continuous with the animals and with animal knowledge. That's page 116. The main task of the theory of human knowledge is to understand it as continuous with animal knowledge and to understand also its discontinuity, if any, from animal knowledge. So we have some overlap between how an animal learns and how a human learns and some things that are different about us, page 117. That is to say, human learning and animal learning may share some epistemological similarities rather than dismiss animal learning as not creating knowledge. But we should also expect human learning to be different in some way, or we couldn't explain why humans lack, why human learning lacks the limits of animal learning. Going back to quoting Popper, in all this, there is, I believe, complete agreement between Campbell and myself.

[00:55:12]  Unidentified speaker: Page 117.

[00:55:14]  Bruce: Popper next praises Campbell's idea of blindness, and points out that he, Popper, had previously made somewhat vague similar arguments. Quote, I am thinking of what Campbell calls the blindness of trials and in a trial and error method. I have sometimes compared the human situation to the quest for new knowledge, with the proverbial situation of a blind man who searches in a dark room for a black hat, which is perhaps not there. This is not saying much, but it indicates that the searcher at least acts as if he has a problem. I have often added that the trial movements of the searcher will not be completely random. There are various reasons for this, both positive and negative. The positive ones are in the main, that the searcher has a problem to solve, and that this means he has some knowledge, however fuzzy, previously acquired by essentially the same trial and error method. This knowledge serves as a guide and eliminates complete randomness, page 117. So there's complete agreement here between Popper and Campbell on the idea of blind variations and also the idea of a ubiquitous hierarchy of variation selection algorithms in nature that build on each other, as opposed to being only two. Quote, Popper quote now, Campbell also explains why he does not call them random, blind variations random, and calls them blind, an excellent term, and insists on the fact that so far as they are trials in the trial and error movement, that is, so far as they are forays into the unknown, they are blind, page 117.

[00:56:53]  Bruce: Earmark that last quote for later when I talk about my disagreement with Ella Hoeppner over how to interpret Campbell. The key thing to note here is that Campbell's blindness is defined in terms of being nothing more than a foray into the unknown. Ella had a disagreement with me over that where I wanted to define blindness that way, she wanted to define it some other way. Popper continues, well, to the degree that past knowledge enters, their blindness is only relative. It begins where the past knowledge ends. Okay, but where do Popper and Campbell disagree? Because so far, it's all agreement. So page 119, Popper says, I come now to two points where I may possibly slightly deviate from Campbell. The first of the two disagreements is underwhelming, in my opinion. Popper claims that Campbell quoted him, Popper, and then said, quote, this insight is the earliest and most frequently noted aspect of an evolutionary epistemology. Popper then says, however, I may perhaps say that in the long passage quoted by Campbell from me, there are, I hope, several insights, and that the insight denoted by Campbell as this insight is not the one I wish to bring out as important. That is, their first disagreement, he's not claiming Campbell was wrong, per se, only that the passage quoted him, quoted had multiple insights, and Campbell found an insight that wasn't the main one Popper intended. That's not much of a disagreement, right? Now, here's the second disagreement that he raises. Quote, I come now to my last comment.

[00:58:20]  Bruce: It is, I think, an important one, and it is related to the difference between man and animal, and especially between human rationality and human science and animal knowledge.

[00:58:28]  Unidentified speaker: This is all page 120.

[00:58:29]  Bruce: Campbell speaks very interestingly of the language of bees, and he also mentions my stress on criticism, but he nowhere seems to allude to my view that human descriptive language differs from all animal language in being also argumentative, and that it is human argument argumentative language, which makes criticism possible, and with it, science.

[00:58:52]  Unidentified speaker: And that's it.

[00:58:53]  Bruce: That's their biggest disagreement. He then continuing quote from Popper, There is a world of difference between holding a belief or expecting something and using human language to say so. The difference is that only if spoken out and thus objectivized, does a belief become criticizable. Before it is formulated in language, I may be one with my belief. The belief is part of my acting, part of my behavior. If formulated, it may be criticized and found to be erroneous, in which case I may be able to discard it. Notice this is an example, contrary to what we've talked about in past podcasts, where Popper is talking about humans having beliefs and doesn't seem to have a problem with it, okay, in this context at least. I do not sense any difference in opinion in what Campbell says concerning truth and instrumentalism, but there seems to be a slight difference in emphasis. In my stress on the idea of truth, on the argumentative function of the human language, and on criticism, in brief, in my predilection for World Three, it is very likely there is no difference here. Campbell's beautiful essay covers a great many things he may have been reluctant to say more.

[01:00:00]  Unidentified speaker: And that's it.

[01:00:01]  Bruce: Popper really doesn't offer even a single disagreement with Campbell on anything. This should close the loophole crit rats are likely to want to use to claim Campbell's Evolutionary Epistemology isn't really Popper's Theory of Evolutionary Knowledge. Okay, that's the end. Go ahead, Peter.

[01:00:20]  Unidentified speaker: Okay, let me just react to this a little bit.

[01:00:24]  Peter: You've put a lot out there. I appreciate that about you. And said some things here and elsewhere on this that I think I agree with, and also some things I'm still wrestling with. So it seems, so let me just make sure I have this right. So it seems like both Popper and the Popper Campbell view and Deutsch's two sources view would fundamentally agree that conjecture and refutation can be thought of as a meta-theory of knowledge. Would you say that's true?

[01:01:06]  Bruce: You know, I think for Campbell and Popper the answers are really obvious, yes. And I can see a case for Deutsches, but I want you to think about this for a second. Okay, the problem is, is that if you were to ask Deutsch the way you just worded it, he'd probably say yes, and he'd say yes, that's what I'm saying, okay?

[01:01:25]  Unidentified speaker: I think so.

[01:01:26]  Bruce: But stop and think about his belief that animal learning doesn't create knowledge, okay? That is a trial and error process, okay? That he's saying doesn't create knowledge, okay? Or think about animal memes. Animal memes is literally cultural knowledge that an animal has, that is adaptive behavior, that then survives because it helps the animals adapt, okay?

[01:01:51]  Unidentified speaker: Okay.

[01:01:52]  Unidentified speaker: No, that makes sense.

[01:01:53]  Bruce: That is not, that has to either be qualified, you have to either under Deutsch's theory, call it not knowledge, and then you don't ask what it is, or you have to call it, somehow that animal meme is knowledge in its genes, even though that's like a blatant contradiction, okay? And when you realize that Deutsch is saying that, then there is a problem with trying to say that Deutsch is saying that the overall meta-theory of knowledge is this theory of trial and error. He's clearly carving out an exception case that he doesn't really talk about, he doesn't really get into, that he doesn't call knowledge, but it behaves exactly like knowledge, and that he doesn't believe it has any, it's unclear if he believes it has any relationship to the meta-theory of knowledge or not, right? That it's related to... And this is why I've objected to it so strongly, right? I understand exactly why the two sources, biological evolution and human ideas, are so much more impressive examples of knowledge growth than animal learning or any of the others that we've talked about. And I've never denied that. I've made a point of saying, look, what's going on here is they're confusing two things, they're confusing how cool open-ended knowledge creation processes are compared to not open-ended knowledge creation processes. So they're trying to declare those the only two sources, because those are the two impressive sources.

[01:03:23]  Unidentified speaker: Okay.

[01:03:24]  Bruce: And the ones that are the center of everything else, like every other source is going to connect back into biological evolution in some way, right? Because there's a hierarchy, you can always trace it back to biological evolution in some way.

[01:03:35]  Unidentified speaker: Okay.

[01:03:36]  Bruce: And in doing that, they are creating... Like think about, think about how... I'm going to get into this in future podcasts, but just as a short preview, let's say I'm arguing with Ella Hoeppner or Dennis Hackethal about, or Vaden for that matter, about Campbell's and Popper's Evolutionary Theory of Epistemology.

[01:04:00]  Unidentified speaker: Okay.

[01:04:01]  Bruce: What they're going to do, all three of them we're going to see, is they're going to carve out something that's not part of Popper's Epistemology and say, well, machine learning, it's doing statistical inference. Machine learning, it's doing blah. And they're going to, Ella didn't, Ella actually called it induction, by the way. But all three of them are going to carve out something that's an exception.

[01:04:23]  Unidentified speaker: Okay.

[01:04:23]  Unidentified speaker: Popper did not do that.

[01:04:25]  Bruce: Campbell did not do that.

[01:04:26]  Unidentified speaker: Okay.

[01:04:27]  Bruce: Modern crit rats do do that.

[01:04:29]  Unidentified speaker: Okay.

[01:04:30]  Bruce: Now, what is this thing, this other thing that exists that animals learn, that adapt their behavior, that allow their behavior? Well, it's not Popper's Epistemology under this theory.

[01:04:39]  Unidentified speaker: Okay.

[01:04:40]  Bruce: It's not evolutionary epistemology.

[01:04:42]  Unidentified speaker: It's what?

[01:04:43]  Unidentified speaker: Well, Ella, as we're going to see, she's going to call it induction.

[01:04:46]  Bruce: She's going to say, well, it's a kind of induction. Popper was not quite right. There is a kind of induction that exists. Well, other crit rats aren't going to go as far as Ella. They're going to say, no, no, no, it's not induction. Induction's wrong. But it's not Popper's either. It's something else. And they're never going to really say what it is, okay? I call this cryptoinductivism. It's exactly the same of inductivism, but it's just not under that name, right? And this is one of the main differences. But because of the Two Sources Hypothesis, because it's a compelling intuition pump that the crit rat community has deeply bought into, okay? They are forced into a sort of belief in induction that, even though they don't necessarily call it that, but they kind of have to go back to something that's just almost the same as induction. And, you know, what's an animal doing? It observes things and then it changes its behavior and it generalizes its behavior. It realizes that based on one observation that the food made it feel sick, it knows not to eat that food again. So based on an observation, it generalizes, okay? Well, if that's not being done through Popper's epistemology, then the only thing left is induction, right? Like, and that's exactly what Campbell and Popper are trying to argue. They're trying to argue, no, that's not induction either. Okay, it's actually Popper's epistemology. Now, is that correct?

[01:06:11]  Unidentified speaker: You know what?

[01:06:12]  Unidentified speaker: I don't know.

[01:06:12]  Bruce: Like, like that's exactly like we have to first understand what Popper was trying to say, which is there's only one theory. It's evolutionary epistemology or what today we would call evolutionary epistemology, since he didn't like that term.

[01:06:23]  Unidentified speaker: And that's it.

[01:06:23]  Bruce: You got one epistemology, it's the way everything works. AI is going to work that way, machine learning is going to work that way, animals are going to work that way. They're absolutely going for the one universal epistemology approach, period.

[01:06:35]  Unidentified speaker: End of story.

[01:06:36]  Bruce: Modern crit rats don't believe that. They believe in something else. And it's a little unclear what they think this other thing is.

[01:06:44]  Unidentified speaker: Okay?

[01:06:45]  Bruce: And what I'm trying to emphasize here is, not that one side's right and one side's wrong, that's a different thing. But that there is a strong disagreement here between Popper and the crit rat community today.

[01:06:58]  Peter: I guess that how I'm thinking of it, what distills it for me is that Popper's ideas don't seem quite, maybe it's a matter of emphasis, but it doesn't seem quite realistic about humans, how special we are. You know, as Deutsch says, there's more differences between individual humans than there are species of animals, which I kind of agree with. But the other side of the coin is that I guess Deutsch's ideas don't seem to do animals learning justice, for many of the reasons you've said. I mean, like, this whole idea that the extreme thing is animals don't have feelings.

[01:07:54]  Unidentified speaker: Yes.

[01:07:54]  Peter: Which doesn't quite...

[01:07:56]  Unidentified speaker: It's just...

[01:07:56]  Peter: It doesn't ring true for me and most people, I think. I mean, if you said animals don't have human feelings, don't have feelings that are based on explanations...

[01:08:09]  Unidentified speaker: Yeah.

[01:08:10]  Peter: But there's something going on that seems a lot like feelings and seems a lot like learning and creating something like knowledge, not open-ended knowledge. But it just doesn't... I think you've gotten at some of the issues with this, how severely this theory is stated, I guess.

[01:08:34]  Unidentified speaker: Yes.

[01:08:35]  Bruce: So, of course, what I'm point... What I'm trying to suggest is that there's a way to actually have it all, right?

[01:08:43]  Unidentified speaker: And I don't entirely know what it is.

[01:08:44]  Bruce: Like, I'm still working it out myself.

[01:08:46]  Unidentified speaker: I really like...

[01:08:47]  Peter: Bringing in the open-ended thing.

[01:08:48]  Unidentified speaker: Yeah.

[01:08:49]  Bruce: So I'm bringing the open-ended thing to try to say, okay, let's admit that certain kinds of knowledge creation are more impressive.

[01:08:55]  Unidentified speaker: Right?

[01:08:56]  Bruce: So yes, you've got kind of this narrow sort of knowledge creation that maybe an animal does. And it's just not as impressive.

[01:09:04]  Unidentified speaker: And let's admit that.

[01:09:05]  Bruce: Let's admit that Deutsch is on to something there.

[01:09:07]  Unidentified speaker: Okay.

[01:09:07]  Bruce: And that Popper kind of, I wouldn't say he missed that because you can definitely find places where he treats humans as very special. We just barely read some quotes about how humans are special because of their argumentative function. Like that's an example of, of course what he means is that we're using explanations there.

[01:09:23]  Unidentified speaker: Right?

[01:09:24]  Bruce: So Deutsch is getting that aspect from Popper. But Popper didn't go as far as Deutsch does, and Popper should have gone further. He should have more strongly stressed the difference between animal learning and human learning. I'm trying to find a way to get have it all, and it's not an easy thing to do. This idea, the idea of Popper that there is one epistemology, okay, that that there is one way in which all truth about the world is known.

[01:09:56]  Unidentified speaker: That may not be true.

[01:09:57]  Bruce: Like Popper could be wrong, and we shouldn't assume, even though it's very appealing point of view, we shouldn't assume it's correct, okay? But assuming it is correct, when it's the only one you know about, that is the right point of view. Okay, so it makes, if you know that you can learn through trial and error, and that's a way to do it, and you don't know of an alternative way to do it, then your first assumption should be, trial and error is the universal way in which learning takes place. Okay, and until somebody can actually say, not just it's done through induction, and then we don't describe what induction is, but somebody says, here is what induction is as a competing theory to Popper's theory, and here's a working example of induction that is not trial and error. Until somebody can actually put up or shut up like that, then actually this idea that there's a single epistemology, that's exactly the right universal stance you should be taking. Because otherwise, your theory is not falsifiable, okay? If you simply throw on there, there's one way to learn, one form of epistemology, and that's Popper's, and then there's this crypto inductivist thing that animals do, right? Then that's animal learning. If you're doing that, right, at this point, since you haven't defined what it is, there's no way to prove you wrong, right? It's a completely ad hoc attachment to the overall epistemology that there's just nothing we can do with, okay?

[01:11:29]  Unidentified speaker: That's the problem with that approach.

[01:11:32]  Peter: So take home point, we shouldn't necessarily rule out that something like a xenomorph from aliens could exist that gains knowledge through harvesting DNA or the borgs from Star Trek who gain knowledge by essentially colonizing other human minds. These things could happen.

[01:12:01]  Unidentified speaker: Somewhere in the multiverse.

[01:12:04]  Bruce: Let me say, let me go ahead and give my opinion.

[01:12:07]  Unidentified speaker: Okay.

[01:12:08]  Bruce: I'm going to do an episode where I'm going to actually give you an algorithm that is an inductive achievement. It's just linear regression, right? Like if you do a linear regression and you don't use backprop and instead you use the normal equations, you can get an inductive achievement and you can form a model, one that like say reads digits, the MNIST data set.

[01:12:31]  Unidentified speaker: I never thought about that.

[01:12:32]  Peter: So these are these are species from science fiction, obviously, based on induction, in a sense.

[01:12:41]  Bruce: Maybe you could argue that they still evolved and that they have a learning algorithm, like since they've never really explained how it is. But yeah, I guess you could argue that they're inductive. So the problem with induction is that it's very vague. And so it's never clear what counts as induction and what doesn't, which is why it doesn't make a good competitor to Popper's Theory, right?

[01:13:01]  Peter: Well, then you also would have to get into some of the stuff gone from Prometheus, where it indicates that the they were actually the xenomorphs created by the engineers. But then the xenomorphs end up, I think they were kind of a bio bio weapon, but then they end up actually killing the engineers.

[01:13:21]  Unidentified speaker: So I don't know.

[01:13:23]  Peter: I'm trying to wrap up to a concluding statement, Bruce.

[01:13:26]  Bruce: But okay, let me make my concluding statement. Because I can point to an example like linear regression, that really does seem to violate Campbell's evolution. And as we've seen Popper's evolutionary epistemology, there's something wrong with it.

[01:13:42]  Unidentified speaker: There is.

[01:13:43]  Bruce: It's not clear if it's a big problem or a small problem. And for a long time, I had this problem that I didn't know how to resolve it. Just go back to episode 26, and I basically admit I have no idea how to resolve this. Like this is long ago now, years ago. And I'm still working on it. I've talked to so many people at this point, Ella and Dennis and Vaden, who all had very similar answers to me, which I found very unsatisfying, like truly unsatisfying answers. The thing is, I can't really say they're wrong. Like, it could be that they're on the right track and Popper was wrong. Like, I see no particular reason why that couldn't be true. But I definitely find it very appealing. Like, what Popper's trying to do is he's trying to make everything be a single epistemology. And that's a super appealing view. If nothing else, if there were two epistemologies, then the correct single epistemology would be the combination of the two. Like, if Popper's was the right epistemology, one of the things that Vaden, we're going to see, does is he tries to declare this other thing not epistemology, okay? But like, if you're doing a machine learning model, and you have one that overfits, or you have one that works, and it actually makes good predictions, both using the exact same method, okay, inductive method, okay? Why does one work and one doesn't? Now, clearly, the answer is that it's got something to do with the fact that it's captured something true about the world. So, machine learning models cannot be dismissed as not related to epistemology at all.

[01:15:16]  Bruce: They are somehow related to epistemology because they connect into, they build models that say something true about the world, okay? No, it's not explanatory knowledge. No, it's not the same as the scientific epistemology. I don't deny any of that, okay? But the idea that you can just declare it not an epistemology is just not true, okay? Based on that, what you really are getting is a declaration of two epistemologies out of the CritRat community. They don't realize that's what they're doing. They would not put it in those terms. But I think starkly speaking, that's the correct terms under which to understand what the CritRat community is arguing. So you've got these two epistemologies, Popper's and this other thing that works for machine learning and AI and animal learning and things like that, okay? When you look at it in that way, you really can't say Popper's epistemology is correct because it's missing this other significant way in which things can learn about the world and can adapt themselves to their environment, okay? Once you realize that, this is really just the same as saying Popper's epistemology is wrong.

[01:16:21]  Unidentified speaker: Now, that might be true.

[01:16:22]  Bruce: Popper's epistemology might be wrong, but we need to get on board with the idea that that's really what the CritRat community is claiming about in here, okay? They're claiming Popper's epistemology is wrong. They're very shy about that today. They want to break it off, not call it epistemology, not call it Popper's epistemology. They want to call it something else. This is a problem. If they were more bold with it, and they were just saying, yeah, actually, we think Popper got this wrong, I would totally find that acceptable. But I've got a problem with just kind of shyly implying it, but not saying it, okay? Be bold about it if this is where you're going. Now, is it true that Popper is wrong?

[01:17:02]  Unidentified speaker: Probably not.

[01:17:03]  Bruce: I eventually did discover Deborah Mayo's theory, which offers a way to fold these counter examples back into Popper's epistemology through the concept of severe learning, severe testing. And I don't know if it's a complete answer. I'm not even sure I fully understand her theory yet. So I'm hesitant to endorse it too strongly until I'm trying to like understand Bayesian reasoning, go back and read her book again, see if I can get it this time. But let me just say that the idea that actually all these examples, machine learning, artificial intelligence, even the linear regression example with the normal equations, that she does offer a possible way to fold it back into all being one epistemology. And that's actually a very appealing thing about her theories.

[01:17:52]  Unidentified speaker: Okay.

[01:17:53]  Unidentified speaker: Again, is it right?

[01:17:53]  Bruce: You know, I don't know. We're not here to back a single theory and be memoids. We want to get it to whatever the truth is. And that means we have to really stop and think about this carefully and have to think about the criticisms very carefully and what the alternative theories that are being offered are.

[01:18:08]  Unidentified speaker: Okay.

[01:18:09]  Bruce: Now, if you were to push me and say, Bruce, what do you think? I think probably Deborah Mayo is right and probably the CritRat community is wrong. I think the CritRat community is on a wrong path and that Deborah Mayo has the correct path. And that really we should be looking at Deborah Mayo's theory and we should jettison the two sources hypothesis that led to this bad path that we're currently on.

[01:18:27]  Unidentified speaker: But you know what?

[01:18:28]  Unidentified speaker: I don't know that.

[01:18:29]  Bruce: Like, it may be that I'm going to change my mind tomorrow and I'm going to say, you know what? The CritRat community has found a legitimate problem here and we really need to start taking it more seriously. Maybe we need to look to the Bayesians to help us understand epistemology better and come up with a synthesis of Bayesianism with critical rationality. I don't anticipate this happening, but who knows? Maybe that's exactly where we need to go. If that's the truth, let's go there. Like, let's not just decide we're Memoids defending a single theory. And this is really why I'm trying to make such a big emphasis here on what Popper actually said and compare it with what Campbell actually said and trying to show that there is zero way in which you can reconcile it with Deutsch's Two Sources Hypothesis.

[01:19:08]  Unidentified speaker: It's impossible to reconcile the two.

[01:19:12]  Bruce: And this is why I'm making a big deal about this. I want people to sharply understand the problem that is being proposed here and not just gloss over it. I want them to take it seriously as a problem. Okay, that's my view at this point. Tentative view. I don't know what else to say at this point. I definitely feel like I only kind of, kind of, sort of understand Deborah Mayo's theory. And so I'm hesitant to proclaim myself as understanding it yet. I will try to understand it. I will do a future podcast on it. And I will try to really make it more clear in my mind and everybody else's mind. But at this point, I'm not there.

[01:19:51]  Unidentified speaker: Okay.

[01:19:52]  Unidentified speaker: Well, Bruce, I've appreciated your thoughts here.

[01:19:54]  Peter: You are on your own unique path in life. And I like that. This is officially not a short episode. Yeah, I don't know if that's possible, but we just it just might not be in the cards for us. But thank you, Bruce.

[01:20:11]  Unidentified speaker: I hope you enjoy this day.

[01:20:13]  Unidentified speaker: Thank you.

[01:20:21]  Unidentified speaker: Hello again.

[01:20:22]  Peter: If you've made it this far, please consider giving us a nice rating on whatever platform you use, or even making a financial contribution through the link provided in the show notes. As you probably know, we are a podcast loosely tied together by the Popper Deutsch Theory of Knowledge. We believe David Deutsch's Four Strands tie everything together. So we discuss science, knowledge, computation, politics, art, and especially the search for artificial general intelligence. Also, please consider connecting with Bruce on X at BNielson01. Also, please consider joining the Facebook group, The Many Worlds of David Deutsch, where Bruce and I first started connecting.

[01:21:05]  Unidentified speaker: Thank you.