Colin McGinn is a well-known philosopher of mind who has written a short piece on the “history of knowledge” on his personal website. He takes an evolutionary view of the topic, which is what he means by “history”. But I found the piece, despite McGinn’s reputation and his authorship of nearly 30 books (many of them on consciousness), confusing and probably misleading. You can read it yourself by clicking on the link below
No doubt McGinn will take issue with my criticisms, for I am but a poor evolutionary biologist trying to understand this the best way I can. However, I do know some biology. I will put what I see as McGinn’s two main misconceptions under my own bold headings, with McGinn’s quotes indented and my own comments flush left.
McGinn conflates “knowledge” with “consciousness”. In general, knowledge, which most people define as “justified true belief” is acquired, and does not evolve. Since it involves belief, it does require a mind that is conscious. (I’ll take consciousness as McGinn does. meaning “having subjective awareness” or “being able to experience qualia: sense perceptions like the feeling of pain and pleasure, the apprehension of color and touch, and so on”.)
The problem is that what evolves is consciousness, not “knowledge”. We do not know whether consciousness is a direct, adaptive product of natural selection, or is a byproduct of evolution, but it is certainly a result of our neuronal wiring. I’ll leave aside the problem of which animals are conscious. Based on parallel behavior, I think that many vertebrates and all mammals are conscious, but of course I can’t even say if other people are conscious. (Remember Thomas Nagel’s famous article, “What is it like to be a bat?” We don’t know.) So consciousness has evolved, perhaps via selection, and it’s likely that the consciousness of many vertebrates had a common evolutionary origin based on neuronal wiring, though again it may have evolved independently in different lineages.
But regardless of these unknowns, since “knowledge” is largely acquired rather than inherited (remember its definition), it’s difficult to see how knowledge can evolve genetically, rather than being learned or passed on culturally. Monkeys and apes peel bananas differently from how we do it: starting from the flower (bottom) end rather than the stem end (try it–it’s easier), but surely that knowledge is not evolved. Anything acquired through experience is not knowledge bequeathed by evolution, even though the capacity to acquire certain knowledge (like learning language) can be evolved.
Now in some cases “knowledge” seemingly can be inherited, so the conflation is not total. Male birds of paradise, for example, “know” how to do specific displays to lure females of their species, and that is an instinct (does that count as “knowledge”?) which is inborn, not learned. But different birds of paradise have different displays or songs, and those displays surely evolved independently based on evolved differences in female preferences. We cannot say with any assurance that the genes or neuronal wiring for one species evolved from homologous genes and wiring in another species. Is one songbird’s knowledge of how to find edible berries evolutionarily related to another the ability of another species of songbird to find food? Both may be learned or both may be evolved, but there’s no reason to think that “knowledge” of different species forms an evolutionary tree the way that their genes do.
You can see this conflation in McGinn’s opening paragraph, which assumes that there was a primordial “knowledge” that gave rise to descendant knowledge:
This is a big subject—a long story—but I will keep it short, brevity being the soul of wisdom. We all know those books about the history of this or that area of human knowledge: physics, astronomy, mathematics, psychology (not so much biology). They are quite engaging, partly because they show the progress of knowledge—obstacles overcome, discoveries made. But they only cover the most recent chapters of the whole history of knowledge—human recorded history. Before that, there stretches a vast history of knowledge, human and animal. Knowledge has evolved over eons, from the primitive to the sophisticated. It would be nice to have a story of the origins and phases of knowledge, analogous to the evolutionary history of other animal traits: when it first appeared and to whom, how it evolved over time, what the mechanisms were, what its phenotypes are. It would be good to have an evolutionary epistemic science. This would be like cognitive science—a mixture of psychology, biology, neuroscience, philosophy, and the various branches of knowledge. It need not focus on human knowledge but could take in the knowledge possessed by other species; there could be an epistemic science of the squirrel, for example. One of the tasks of this nascent science would be the ordering of the various types of knowledge in time—what preceded what. In particular, what was the nature of the very first form of knowledge—the most primitive type of knowledge. For that is likely to shape all later elaborations. We will approach these questions in a Darwinian spirit, regarding animal knowledge as a biological adaptation descended from earlier adaptations. As species and traits of species evolve from earlier species and traits, so knowledge evolves from earlier knowledge, forming a more or less smooth progression (no saltation). Yet we must respect differences—the classic problem of all evolutionary science. We can’t suppose that all knowledge was created simultaneously, or that each type of knowledge arose independently. And we must be prepared to accept that the origins of later knowledge lie in humble beginnings quite far removed from their eventual forms (like bacteria and butterflies). The following question therefore assumes fundamental importance: what was the first type of knowledge to exist on planet Earth?
Note that he implicitly envisages an evolutionary tree of knowledge. It would be clearer if he used “consciousness” for “knowledge”, and defined both of them, which he doesn’t. But even if you think that, well, McGinn may be onto something here, that “something” comes crashing down when he starts talking about what “knowledge” was the ancestral knowledge. This brings us to the second problem:
McGinn is dead certain that the first “knowledge” that evolved, by which he really means the first quale, or subjective sensation, is the experience of pain. There is no evidence , or even a convincing scenario, for this proposition. Here’s where he proposes this, and not with much doubt, either:
I believe that pain was the first form of consciousness to exist.[1] I won’t repeat my reasons for saying this; I take it that it is prima facie plausible, given the function of pain, namely to warn of damage and danger. Pain is a marvelous aid to survival (the “survival of the painiest”). Then it is a short step to the thesis that the most primitive form of knowledge involves pain, either intrinsically or as a consequence. We can either suppose that pain itself is a type of knowledge (of harm to the body or impending harm) or that the organism will necessarily know it is in pain when it is (how could it not know?). Actually, I think the first claim is quite compelling: pain is a way of knowing relevant facts about the body without looking or otherwise sensing them—to feel pain is to have this kind of primordial knowledge. To experience pain is to apprehend a bodily condition—and in a highly motivating way. In feeling pain your body knows it is in trouble. It is perceiving bodily harm. Somehow the organism then came to have an extra piece of knowledge, namely that it has the first piece, the sensation itself. It knows a mode of knowing. Pain is thus inherently epistemic—though not at this early stage in the way later knowledge came to exist. Call it proto-knowledge if you feel queasy about applying the modern concept. We can leave the niceties aside; the point is that the first knowledge was inextricably bound up with the sensation of pain, which itself no doubt evolved further refinements and types. Assuming this, we have an important clue to the history of knowledge as a biological phenomenon: knowledge in all its forms grew from pain knowledge; it has pain knowledge in its DNA, literally. Pain is the most basic way that organisms know the world—it is known as painful. Later, we may suppose, pleasure came on the scene, perhaps as a modification of pain, so that knowledge now had some pleasure mixed in with it; knowledge came to have a pain-pleasure axis. Both pain and pleasure are associated with knowledge, it having evolved from these primitive sensations. This is long ago, but the evolutionary past has a way of clinging on over time. Bacterial Adam and Eve knew pain and pleasure (in that order), and we still sense the connection. Knowledge can hurt, but it can also produce pleasure.
When you poke an earthworm, it recoils. Does it do so because it feels pain? I doubt it, as it seems to me unlikely that an earthworm is conscious. Perhaps it just has an evolved neuronal network and morphology that retracts the body when it senses (not consciously) that it’s been touched. It could simply be like our kneejerk reaction: a reflex that evolved, but is not perceived consciously (remember, we take our hand off a hot stove before we are even conscious of feeling pain). But even if you think earthworms are conscious, certainly single-celled animals are not, yet they exhibit adaptive behavior as well. One-celled animals can move toward or away from light, are attracted to chemical gradients that denote the proximity of food, move away when disturbed by a touch, seek out other individuals for reproduction, and so on. All animals, whether you think they’re conscious or not, have some kind of evolved instinct to find individuals of the opposite sex when it’s time to have offspring. And surely that “knowledge” (if you will) is the most evolutionarily important of all.
Why, then, is awareness of pain supposed to be the very first “knowledge” to evolve? Why not responses to touch, to chemical gradients, to a drive for reproduction, or all the qualia that involve senses: touch, taste, sight, hearing, hunger and thirst, and so on? All of those can be seen as adaptive as a sense of pain, whether it be conscious or not.
Seeing various behavioral responses as constituting “knowledge”, then, adds nothing to our understanding of either evolution or consciousness. It muddles one’s thinking. The problem is instantiated by sentences like this one:
The organism knows how to get about without banging into things and making a mess. We could call this “substance knowledge”.
Well, simple organisms like rotifers also avoid obstacles. They are almost certainly not conscious, and you can’t have knowledge without consciousness. Do they “know” how to get about without banging into things, or is it an evolved trait based on cues associated with “being touched”. What “knowledge” is being shown here?
McGinn then proposes, with near certainty, an evolutionary progression of “knowledge”:
So, let’s declare the age of sense perception the second great phase in the development of knowledge on planet Earth. The two types of knowledge will be connected, because sensed objects are sources of pain and pleasure: it’s good to know about external objects because they are the things that occasion pain or pleasure, and hence aid survival.
I will now speed up the narrative, as promised. Next on the scene we will have knowledge of motion (hence space and time), knowledge of other organisms and their behavior (hence their psychology), followed by knowledge of right and wrong, knowledge of beauty, scientific knowledge of various kinds, social and political knowledge, and philosophical knowledge. Eventually we will have the technology of knowledge: books, libraries, education, computers, artificial intelligence. All this grows from a tiny seed long ago swimming in a vast ocean: the sensation of pain.
The “knowledge” of right and wrong is a learned and cultural phenomenon, completely unlike our “knowledge” of pain, whether it be conscious or a simple reflex reaction to harmful stimuli. What bothers me about all this is not just the mere conflation of “knowledge” with “consciousness”, or the idea that pain was the first “knowledge”; it is the sheer certainty McGinn displays in his essay. Perhaps that comes from his being a philosopher rather than a biologist, as biologists are surely more cautious than philosophers. A quote:
It was pain that got the ball rolling, and maybe nothing else would have (pain really marks a watershed in the evolution of life on Earth).
I could say with just as much evidence that the perception of touch (either conscious or as an evolved reflex) “got the ball rolling”. And a response to touch in simple organisms cannot be construed as “knowledge” in any respect.
There is more in this article, but I find the whole thing confusing. We don’t even know whether consciousness evolved as an adaptive phenomenon. We don’t know whether our consciousness is a post facto construct for perceiving qualia that the body has already detected (remember, you pull your hand off a hot stove before you feel pain). Above all, we don’t know the neuronal basis of consciousness, much less which animals are conscious and which are not. In Matthew Cobb’s biography of Francis Crick, you can see his subject struggling with this issue in the last part of his life, and admitting that we know little about it. Crick laid out a program for sussing out the neuronal basis of consciousness, but, as Matthew noted in these pages, scientists haven’t gotten far with this problem.
I have no idea why McGinn is so certain about evolution and qualia. I don’t know any evolutionist who would agree with his thesis. I even broached it to a neurobiologist who knows evolution, and that person found the whole concept totally misguided.
As I said, McGinn is no slouch; he is a highly respected philosopher whose work I’ve read and respected. But I get the feeling that he’s driven out of his lane here.





























