Easy Cosmology

It took over 2000 years to discover the correct cosmology: the one formulated by Isaac Newton. The features of this cosmology include a heliocentric solar system, a moving earth (diurnal and annual), a unified theory of terrestrial and celestial motion, a universal force of gravity, elliptical orbits, and an account of moons, comets, and satellites. All sorts of contrary ideas were tried out and widely believed during this time of slow discovery, some completely wacky (by modern standards). Mysticism and religion stood in the way of truth. It wasn’t easy to arrive at the correct theory.[1] Why is this—why so difficult? Is it that the theory is extremely complex or requires advanced mathematics or is intrinsically counterintuitive or includes paradoxes (like quantum theory)? No, it is none of these things: it is just that the facts are not open to casual observation. We can’t just look and see. We can’t observe the motion of the earth from our position on its surface; we can’t see what other planets are like from close up; we can’t simply track the elliptical orbits of the planets with our eyes. If we could sense the earth’s motion, we would not need convincing indirect evidence of it; but inertia gets in the way of such observation (we move with the earth so that it seems stationary to us). If we could train our eyes on the planets and observe their likeness to earth, we would immediately conclude that motion has the same causes here and elsewhere; we wouldn’t speak of sublunary and superlunary zones. If we could sit back and watch the planets move, as we watch birds fly, we would see that they move in ellipses not circles. If we could take a trip to outer space, we could see the shape of the earth, its antipodes, and its diurnal rotation—none of these being observable from our earthbound position. The difficulty with arriving at the correct cosmology arises from our location and sensory limits, not from anything intrinsic to the theory. The theory itself is simple, straightforward, and not conceptually problematic (I leave aside the mysterious nature of gravity and confine myself to questions of cosmic architecture). It just so happens that we can’t simply use our senses to get at the truth; in principle, however, the truth is open to sensory observation. The facts are observable facts (macroscopic material bodies moving through space according to normal geometry); it is just that we cannot observe them. It’s really a question of distance and the invisibility of the earth’s motion. The universe itself isn’t intrinsically hard to grasp in the relevant respects; it is actually quite simple, quite transparent, quite commonsensical (ellipses are not less comprehensible than circles). The difficulty of cosmology is entirely observer-relative, and quite adventitious. No doubt Newton was a genius in coming up with the theory, but any ten-year-old can grasp the content of the theory: it’s just not that hard. The earth moves; the sun is stationary; the earth goes round the sun in an elliptical orbit, as do the other planets; the sun exerts a force on the planets causing them do this. What’s not to understand? Suppose people were surrounded by thick clouds all the time. They can’t see what is above them. Occasionally they catch a glimpse of what lies on the other side of the clouds, but nothing very definite. Nevertheless, they formulate theories of their little cosmos; these theories are inevitably pretty wacky, given the slender observational basis (something about a celestial central fire, angels moving ethereal bodies about, that type of thing). Then one day the sky opens up with a clear view of what lies only a short distance above their heads: pieces of paper and dead leaves swirling around in the wind—nothing very spectacular or supernatural or sophisticated. Feeling rather let down, they substitute this new vision for the visions of their imagination in days gone by: this now is their official cosmology—disappointingly mundane but at least true. Well, that is like our position with respect to our (local) cosmos: we couldn’t see it too well, so we invented fanciful theories of what is going on, but now we see that it is nothing very remarkable. Admittedly, it took us 2000 years to arrive at the mundane truth (compared to the mystical mathematical supernatural nonsense concocted earlier), but at least it’s true: bits of rock flying through space, pushed around by gravity, with nary an angel in sight (or even a perfect circle). Not all science is like that: sometimes (often) the correct theory is hard to arrive at not because of human sensory limitations (particularly in regard to distance) but because the theory is genuinely unobvious and taxing even when the observational facts are in. I would say this about atomic theory, big bang cosmology, evolution by natural selection, botany, and chemistry (among others). The theory of photosynthesis, for example, is a complicated and unobvious theory; the difficulty of arriving at it doesn’t derive from a simple sensory limitation (we have the plants right in front of us). Similarly for Darwin’s theory: it takes ingenuity to come up with that; you couldn’t just observe it to be true if your eyes were more capacious. In the case of the atom, we might think that more discerning eyes would reveal the structure of the atom (but could we ever really see an electron?), but it takes more than that to figure out the dynamics of the particles composing an atom. That is, there are real theoretical problems in these areas not just a blanket of clouds or sheer distance. Improved vision wouldn’t make these problems go away. But in astronomy (the part we are concerned with anyway) the theory would be automatic once the senses have done their work: the trouble is the senses can’t do their work. The problem is location not cerebration, physical distance not intellectual depth. Newton’s work on optics falls into this latter class; his work on planetary motion falls into the former class. This is why we all understand the outlines of Newton’s celestial mechanics but we find his work on optics more daunting—because it calls for theoretical understanding. Light is intrinsically hard to understand, but planetary motion is not (it’s just stuff moving through space subject to forces). Philosophical problems lie at the extreme end of the non-observational class of problems: the difficulty of the mind-body problem, say, does not derive from observational paucity due to distance or clouds; it is purely theoretical. We don’t need a better look to solve this problem but better thinking (theory construction). The solution will not be mundane (though hard to arrive at), like Newton’s theory. It won’t take the form of neurons orbiting each other in ellipses, or one part of the brain being stationary while the rest moves, or some such thing. There is something bathetic about Newton’s theory, given the history of astronomy, but surely the solution to the mind-body problem will be anything but bathetic (like concluding that consciousness is a result of neural length). So, there is a contrast between the science of astronomy and other sciences (including philosophy): astronomy up to Newton was hampered by observational limitations, but the other sciences face theoretical problems inherent in their subject matter. Thus, Newton’s theory is easy to grasp though difficult to arrive at, whereas the other theories are not easy to grasp—and hard to arrive at largely for that reason. Of course, discovering and formulating the laws of motion requires theoretical ingenuity, and gravity itself is deeply puzzling, but the basic architecture and dynamics of the solar system are of the same order as ordinary observable phenomena—bodies moving in straight and curved paths through space. The only question was which bodies are moving and along what paths.[2]

[1] Just how tortuous and faltering it was is brought out in Arthur Koestler’s very thorough The Sleepwalkers (1959).

[2] The only area I can think of that compares to astronomy is geography. Here too it was millennia before accurate maps of the earth were produced, simply because the layout of the earth is not visible from anywhere on it (even from a mountain top). It was necessary to travel all over the earth to be able to devise adequate maps. In astronomy it wasn’t possible to travel to the stars, but at least you could see them (some of them) from planet earth. Not surprisingly, there wasn’t much variation in different parts of the earth, as there is not much variation between different stars (compared to what used to be believed). The physical universe is pretty homogeneous no matter where you go (it is made of the same stuff after all). A Newton of geography would not have any very remarkable geographical facts to report; that is why geography is a boring subject content-wise. Astronomy is the geography of the skies (also the physics). What it isn’t is a window into the mind of God, or a repository of mathematical and musical harmony, or the basis of astrology.

An Argument Against Skepticism

The skeptic claims that we are wrong to credit ourselves with knowledge. Our belief that we possess knowledge is a false belief: we make an error when we ascribe knowledge to ourselves. But why do we make this error? On this question the skeptic is strangely silent: we are not told what the source of the error is and why we fall into it. This is unsatisfactory: surely an error this large, this persistent, should have an explanation. The skeptic owes us a theory of the error he imputes. The error that the earth is stationary lasted for millennia and was difficult to dislodge, but it is an understandable error, given our location and the facts of physics (inertia etc.). Not for no reason did people cling to the error in question. Similarly for the error (if it is one) that objects are objectively colored, which was not detected until the seventeenth century (initially by Galileo). This error can be seen to arise from the way objects look: they look objectively colored. In general errors have explanations; they are not gratuitous, groundless, inexplicable. If we cannot explain the error, the claim that it is an error is pro tanto dubious, especially if the claim of error rests on convoluted argument. So, the skeptic needs to meet this challenge or else concede weakness in his position; at the very least the question should be acknowledged and addressed. Why do we falsely believe that we have knowledge if the skeptic is right in saying that we demonstrably do not? The arguments for skepticism are not complex and can be easily grasped, so why have they not undermined the belief in knowledge long ago? Why do we even have the concept of knowledge if the concept is never (or seldom) instantiated? Is it perhaps that the skeptic is wrong and we do have knowledge in the cases where we believe we do?

            Here is a possible explanation: we are under the illusion that we have knowledge. There are well known visual illusions that produce false beliefs, and we can envisage more pervasive types of visual illusion (such as the illusion that objects are objectively colored). But this is not a plausible explanation: for we don’t perceive instances of knowledge by means of the senses. It isn’t as if it looks as if knowledge exists but it really doesn’t (like the proverbial pink rats). We don’t perceive knowledge at all, so there can’t be sensory illusions of knowledge. Nor is it plausible that the word “knowledge” encourages the error: we don’t believe we have knowledge because the word intimates that we do; it isn’t that the word is a very vivid name that conjures up a non-existent referent. So, it is a mystery why we commit and persist in the error, finding ourselves shocked when the skeptic mounts his assault. And the skeptic never concludes his assault by saying, “And the reason you commit the error I have just exposed is X”, where “X” stands for the error theory we are searching for. Moreover, we don’t typically respond to the skeptic’s argument by saying immediately, “Oh silly me, how could I have made this error for so long?”. On the contrary, the alleged error is remarkably resistant to revision (as Hume pointed out); we don’t simply abandon the belief in knowledge forthwith. In other cases of error, even ancient and universal error, reason prevails and the error is corrected; but skepticism has made little progress in removing the erroneous beliefs it attacks, though it has been around for over 2,000 years. We just don’t respond to it as one whose error has been convincingly exposed. What is the skeptic’s explanation of this resistance—if not that there is really no error that is being exposed? It’s surely not simple dogmatism and arrogance—epistemic overestimation—since it really does seem to us that we know things about the world. We sincerely believe that we have genuine knowledge of things; it’s not that we only act this way in order to impress others. That is why skepticism comes as a shock to the system.

            Note that this point doesn’t tell us what is wrong with the skeptic’s arguments; it merely suggests that something must be wrong. The next task would be to identify precisely what that something is. But it does indicate what is peculiar about skeptical doubt, namely that it is removed from ordinary sources of error. In the normal course of things, we experience no difficulty in recognizing error, explaining it, and revising our beliefs accordingly. For example, we might come to see that we were subject to a visual illusion that gave rise to a false belief, so that we were wrong to think that we had knowledge. It is well within our powers to change our attributions of knowledge to ourselves. Here there is no problem with supplying an error theory and changing our epistemic beliefs because of it. But what explains my erroneous belief that I know there is an external world? It isn’t that I have recently discovered that I am a brain in a vat—that would certainly explain my false belief that I know there is an external world! But the problem is that there is no such explanation of why I erroneously believe that I know there is an external world, even if there is. Maybe I don’t know this, as the skeptic argues, but why do I believe that I know it to begin with? Why didn’t I recognize before that my belief that I know is shaky or baseless? Why did it take the skeptic to make me aware of this? What if skepticism had never been invented so that no one ever questioned their general beliefs about things (the external world, the past, other minds)? What would explain such massive error, on the assumption that I simply don’t know such things? Why do human beings so confidently believe that they have knowledge when they don’t? The error seems utterly inexplicable (if error it is). Isn’t it more likely that there is no error and we really do know? False astronomical beliefs are easy to explain, or false biological beliefs, but false epistemic beliefs are not like this—why are we wrong in our beliefs about what we know? To put it differently, why are we so wrong about which of our beliefs are justified? Maybe we are wrong, but we need to be told why we would make such a basic mistake. Are we just stupid? But lots of very smart people think we have knowledge, so it can’t be a matter of low IQ. Is it that we have such beliefs by instinct and don’t question them? Is the explanation that we are programmed genetically to believe we have knowledge? But what reason is there to believe that, and why can’t we rationally question such an instinct once reason gains a foothold in our minds? Nor is the belief instilled in us by something akin to religious indoctrination. None of the standard explanations for error works, so the skeptic has an undischarged obligation. We are guilty of a conceptual error, according to the skeptic, but what explains this error has yet to be diagnosed.[1]

Colin McGinn

[1] A similar challenge is faced by the opponent of free will: if there is no free will, why do people think there is? But here there are viable options: people might be confusing genuine freedom with mere freedom from coercion, or there might be a phenomenology of freedom that coexists with actual determinism. In the case of skepticism, however, nothing suggests itself, so the skeptic is left with an unexplained error, and one that cries out for explanation. Not that skepticism lacks intuitive force and powerful arguments in its favor, but it also faces intuitive and powerful counterarguments. I am just adding a further consideration into the mix, not trying to resolve the issue one way or the other.

Novels

Someone once described my first novel Bad Patches as a “punk existentialist” novel. I thought this an apt description. Written in the early Eighties, when punk was still alive and kicking in the UK (“Anarchy In”), the central character, Dave Green, is abrasive, abusive, resentful, unpleasant to be around, and generally repellent—though not without a certain rough charm. He wants to make it in modern England as an artist, but is condemned to be either unemployed or working in an off-license in Earl’s Court (where I used to live). He drinks a lot, chases girls, and says nasty things about his friends (Mick, in particular, a big violent lad, perpetually drunk). But he is also an existentialist of sorts: a stranger in an alien world, uncertain of his values, but above all authentic. Oh, he is authentic all right, authentic to a fault. Dave speaks his mind, he acts freely and with abandon, he doesn’t sugarcoat it. He is an artist, after all—a believer in the truth, no matter how ugly. He is brutally honest, a Johnny Rotten of the art world (and off-license). He belongs with the characters in the TV sit-com “The Young Ones” (a parody of the earlier Cliff Richards pop song of that name). The novel itself is a comedy, though certainly of the wincing and whining kind. It is of its time, politically and philosophically. John-Paul Sartre meets Rik Mayall: nausea and nastiness (but you have to laugh).

            My second novel, The Space Trap, written in the early Nineties, is very different. The central character, Alan Swift, is a dull dad working in an insurance office. He lives in his imagination and dreams of escape. There is nothing punk about him (post-punk, you might say). He is persecuted by his humdrum environment: the moths that invade his flat, the shattered windscreen, the annoying co-workers, the demanding and unsympathetic wife (as he sees it). He’s gotta get outta this place. His world resembles that of the British TV series The Office, which came along several years later. Like David Brent, who also works in a dull office but lives in his imagination, Alan Swift is subject to unconscious forces he cannot control. As it happens, Ricky Gervais studied philosophy at University College London, where I used to teach, but he came along just after I had left. I have often wondered if he read my novel, because the office I describe is remarkably like the one he created. But in my novel Alan does escape to the world of his imagination—he moves to New York, leaving his family behind and not telling them he is going. I used to call this novel a Kantian soap opera: not punk existentialist but working stiff psychoanalytic (Kantian because of the emphasis on the inescapability of space). It also is a comedy, though gentler than Bad Patches, more sad-sentimental and domestic-depressing (but you have to laugh).

Easy and Hard Problems

It has become customary to speak of “the hard problem of consciousness” and “easy problems [of consciousness]”. I think this is an unhelpful way to talk; it is too simple-minded. In the first place, we should not say that consciousness itself is a hard problem; rather, its relation to the brain is a hard problem. That is, the brain-consciousness problem is a hard problem. There is nothing about consciousness as such that is particularly perplexing; it’s not like the quantum world or the behavior of schizophrenics. On the contrary, much of consciousness is well known to us and not a source of puzzlement (we don’t wake up every morning and feel bemused about our consciousness). Consciousness is only a major problem in relation to the brain, and only because of the “explanatory gap”. The problem is how the brain could produce consciousness (if “produce” is the right word): so, it is really a problem about the brain. We should be speaking of “the hard problem of the brain”, i.e., the problem of how the brain contrives to generate consciousness. We can explain how the brain produces behavior (more or less), but we can’t explain how it produces conscious experience. It is the mind-brain problem that is hard. But is there any easy part of that problem? Don’t say, “Yes, because explaining behavior is (relatively) easy”; that isn’t an aspect of the mind-body problem. I suggest that there are no easy explanatory mind-body problems to speak of; all the problems are hard. True, it is relatively easy to establish psychophysical correlations and psychophysical causation, but these are not explanatory problems. Nothing about consciousness is explained by brain science: not its subjectivity, not its intentionality, not its rationality, not even its propositionality. So, there are no easy mind-body problems of an explanatory nature—though there are easy behavior-body problems. There are, however, easy problems of consciousness: its general characterization (“there’s something it’s like”), its contents at a given moment, who has it and when, its various types (perception, thought, emotion, sensation, etc.). It is therefore quite misleading to say baldly that consciousness is a hard problem; or that some parts of the mind-body problem are easy. Some (most?) of consciousness is easy, and all forms of the mind-body problem are hard. We do better to speak of easy and hard problems of the brain: behavior easy, experience hard. Also, we should not give the impression that only the conscious part of the mind raises a hard mind-body problem; the unconscious mind raises one too.[1] All in all, the usual way of talking these days is massively misleading and should be abandoned.

There are other defects in the received terminology. First, it is too dichotomous: we are offered a two-way distinction between easy and hard problems. But surely, we need finer distinctions than that: we need really easy problems, easy-ish problems, pretty hard problems, hard problems, super hard problems, and terminally hard problems. Difficulty clearly comes in degrees and is not binary affair. Maybe the various mind-body problems vary in their degree of hardness, while all being pretty damn hard. Second, the standard talk makes no allowance for the possibility of subject-relative hardness:  perhaps no problem is hard simpliciter but only hard for this or that form of intelligence. Then we should speak of the “hard-for-us problem of X”. Third, the use of “hard” here fails to signal an essential feature of the type of problem it purports to describe, namely that the thing in question is a mystery. When Chomsky first introduced the division of question types into two kinds he spoke of “problems” and “mysteries”, not of “easy” and “hard” problems. This avoids suggesting that serious scientific questions are easy to answer, and it signaled that some questions move into a region beyond the merely “hard”: these questions completely baffle us, are difficult even to formulate, and suggest no workable methodology for their eventual solution. The word “mystery” captures this category of questions perfectly.

A question seldom asked by those who favor the “easy-hard” terminology is whether it generalizes beyond the case of the mind-body problem. I would say yes (though preferring the “problem-mystery” terminology). There are easy problems of matter and hard problems of matter: how to calculate a trajectory is easy, understanding quantum theory is hard. And there are other problems in physics that deserve to be called hard, which have been discussed elsewhere.[2] There are also hard problems in biology, notably the origin of life on earth, compared to easy problems (what species humans evolved from, for example). Some fall between these extremes, like the question of why sex evolved (this one might be categorized as “surprisingly hard”). Then we have moral problems: it is easy to see that one ought to return what one has borrowed but hard to decide what we owe to future generations. Again, we must avoid binary thinking and allow for all manner of gradations and varieties of difficulty, but it is certainly helpful to rank outstanding problems on a scale of hardness. I myself think that intentionality is an easier problem than subjectivity, though both are up there in degree of difficulty. The simple “easy-hard” distinction is really a way to avoid serious thinking not an example of it. Like many a catchy label, it hampers rather than helps.[3]

Colin McGinn

[1] See my paper “The Mystery of the Unconscious” in Philosophical Provocations (2017).

[2] See my Basic Structures of Reality (2011) and We Have No Idea, by Jorge Cham and Daniel Whiteson (2018).

[3] It is true that in “Can We solve the Mind-Body Problem?” I described consciousness as the “hard nut of the mind-body problem”, but I never subscribed to the “easy-hard” distinction as it came to be formulated subsequently. Nor did I ever use the phrase “the hard problem of consciousness”.