Philosophy Summarized

Philosophy Summarized

Philosophy is a human construction with a human history, like art and politics. It has origins, antecedents, revolutions, and counterrevolutions. It evolves. I am going to describe this history from Descartes to the present day. The brush will be broad but hard-edged. It is all about Descartes and reactions to him. He had two main problems: the problem of knowledge and the matter-mind problem. Impressed by skepticism, he sought to place knowledge on a firm foundation; it wasn’t going to be easy. Eventually he resorted to proving that God exists and then asserting that God is no deceiver. This is not what we would have expected: one would think that ordinary knowledge claims could be grounded on ordinary facts not theological speculations. He introduced theological epistemology—epistemology denaturalized. Not many people have found this persuasive. On mind and matter he offered two theories: mechanism about matter and anti-mechanism about mind. Hence radical dualism: two quite different substances standing in an uneasy relation to each other, one material the other immaterial. One might have thought that something less drastic would be forthcoming, not a cosmic schism. Not many people found Cartesian dualism attractive. Notoriously, it couldn’t explain psychophysical interaction (pineal glands are not miracle workers). Less noticed, it couldn’t explain knowledge either: for how could knowledge (a state of the immaterial substance) be causally explained by mechanism and extended bodies? Yet Descartes had put his finger on two sore points and said something—the problem of justifying knowledge and the problem of joining mind with body. The trouble is that what he said was hard to take seriously, try as one might. He revolutionized philosophy only to put it in peril of incoherence and absurdity. Cartesian philosophy was in a state of crisis from the start.

The reaction was swift though divided. On the one hand, we had empiricists like Locke and Hume who sought to secularize knowledge and sidestep skepticism (Berkeley simply eliminated matter and put God in its place). They had little positive to say about the mind-body problem, though they disdained Cartesian dualism. Still, the empiricists had a theory about how knowledge is possible, rooted in the idea that knowledge is a faint copy of sense experience. On the other hand, we had the rationalists who attacked Descartes’ dualism: Leibniz with this monadology of multiple immaterial monads (a kind of democratized idealism), Spinoza with his one big infinite substance that packs in God, mind, and matter. It cannot be said that these non-dualistic theories garnered many adherents, though they were comparably mind-boggling. What about the idea that the one big substance is actually a hive of small buzzing monads? It cannot be said that the conundrums posed by Descartes were resolved by these responses. Kant entered the fray and tried to find a middle ground: knowledge is of a phenomenal world that reflects the structure of the human mind, and the mind-matter problem gets safely tucked away in the noumenal world of which we know nothing. This was another form of idealism coupled with a dose of ontological duality—the known and unknown.

Now we skip ahead to the twentieth century and the ground begins to clear, the options narrowed down. The two problems continue to dominate; Descartes is still on everybody’s mind. Empiricism is the order of the day, diluted and qualified, but alive and kicking. Science gets in on the act. Degrees of empiricism are distinguished and marketed: full-on phenomenalism, inference to the best explanation, logical positivism, Popper’s critical philosophy, Husserl’s phenomenology, Quine’s stimulus-response behaviorism. Skepticism hovers menacingly in the background, never quite resolved. Meanwhile the mind-body problem intensifies and ramifies: we get reductionist physicalism, token identity theory, behaviorism, functionalism, panpsychism, eliminative materialism. It tends to be uniformly anti-Cartesian, though with some true believers hanging on for dear life. Matter comes to be the preferred mode of reality, though with ingredients added (property dualism, neutral monism, Wittgenstein’s anthropological naturalism). Descartes’s mechanism persists (sans ghost). These views have their adherents and apologists, though they cannot boast universal acceptance. Descartes hangs heavy over the proceedings. We live in a post-Cartesian philosophical world.

These two problems afflict other areas of philosophy not just epistemology and metaphysics. I will mention ethics, language, and mathematics. We have the problem of ethical knowledge: how do we know ethical truths—do we even know them at all? What kind of experience could they be based on? Are there really ethical propositions? Then we have the problem of how values fit into the world as a whole—the value-fact problem. There is clearly a relation, but what is that relation—identity, supervenience, expression? In the philosophy of language, we have the problem of knowledge of meaning and the problem of how meaning is related to the world. Is semantic knowledge a kind of ability or disposition or justified belief or image or brain state? And what is reference—that elusive relation between words and things? Is it a kind of isomorphism or a causal relation or an exercise of intuition or nothing at all? This is the meaning-world problem, analogous to the mind-body problem. In mathematics we likewise wonder about the nature of mathematical knowledge and how mathematics relates to the non-mathematical world. Do we perceive numbers and with what kind of causality, what grounds our certainty about mathematical truths, are numbers really there to be perceived? And does mathematics somehow arise from the empirical world, or is it an autonomous realm, or pure fiction? The same pattern is recurring in each area—the Cartesian pair. It seems to define philosophy as it we have it; it underlies the history of the subject.

Can we envisage an alternative to this pattern? Is there a way out of it? Can we question Descartes’ assumptions. Two things seem obvious: Descartes didn’t know how we know and he didn’t know how mind and matter are related. He developed theories that undertake to supply the knowledge we lack. Let’s look at the mind-body problem again. Our mind knows about itself—we call this introspective knowledge—but it doesn’t know about our brain. We know about our brain by means of our external senses; introspection is powerless in this regard. Similarly, our brain doesn’t know about our mind: that is, if our brain were equipped with a faculty for knowing itself, this would not add up to knowledge of the mind (recall the “knowledge argument”). We thus lack the kind of bridging knowledge that would potentially solve the mind-body problem; we can’t acquire the necessary knowledge from knowing our brain and knowing our mind. The mind-body relation is a mystery to us—one that requires for its solution a type of knowledge that transcends our ordinary methods of knowing (perception and introspection). It requires what might lamely be called “theoretical knowledge”. What about our knowledge of knowledge? To know about that would require two things: knowledge of knowledge as a psychological phenomenon and knowledge of the nature of the world known. Do we possess such knowledge? We do not—not deeply anyway. We have a lot of trouble even defining knowledge, let alone understanding it as an achievement of consciousness (with which it is intimately connected); this is a longstanding philosophical problem. Nor do we have very penetrating knowledge of the reality known: we don’t know the underlying nature of matter, or space and time, or natural laws, or causality, or other minds. It doesn’t seem to us to be intrinsically knowable.  We are thus ignorant of both things—the things that together constitute knowledge. We don’t have a theory of knowledge—knowledge of knowledge. Accordingly, knowledge of reality is mysterious to us[1]—like the mind-body relation. Descartes could have said, “I know so little about the mind and the world, and the mind and the brain, that I don’t feel able to comprehend how knowledge is possible or how the brain and mind interact”; but he didn’t—he tried to forge theories from thin air. These theories were ingenious enough, but quite batty—just not credible. His successors saw this immediately but proceeded on the same assumptions as Descartes—a kind of unwarranted presumptuousness about human faculties of understanding. Hence the history of the subject. What if he had said, “Of course, these theories are mere speculation on my part; it may be that my cognitive faculties are inadequate to the task I set before them”. That might have changed the course of history. In particular, subsequent philosophers would have been able to avoid striding confidently down blind alleys. They could have still wandered down those alleys—they are interesting to explore—but they would not have exhibited such overconfidence (exactly what Socrates had warned them against two thousand years before). It turned out that Descartes was quite wrong about the nature of matter, as later physics revealed, and his psychology was primitive at best, and his biology was nonexistent—and his immediate successors were not much better. It is not wise to venture dogmatic theories concerning things about which you are blaringly ignorant; they are apt to be wrong. Maybe our philosophers should have followed Popper’s critical philosophy and claimed only that their theories had not yet been falsified. The epistemology of philosophy should have been more self-critically considered. Human nature got in the way of the history of human philosophy.[2]

[1] As a priori knowledge is generally taken to be, often to its discredit.

[2] Is this because philosophy was aligned with religion and religion is characteristically dogmatic? Probably. Religion gets you accustomed to wacky dogmas, so you tolerate them in philosophy. Descartes had this kind of education. What if less of a genius, say John Locke, had initiated the modern period with his more plodding but sensible reflections? As it is, a great deal of modern philosophy consists of replies to Descartes, including Locke. Descartes preferred certainty to doubt, solutions to mysteries. He was a “solutionist” not a “mysterian”. The entire tradition has a solutionist flavor, thanks to Descartes.