A response to Owlmirror on Pharyngula,
You suggest that idealism is incoherent because 1) it doesn’t explain “things acting under purely physical rules, rather than mental states.”
-What is a physical rule, exactly? How are these rules or laws determined, and why, as in the case of our particular universe, are they so organized as to sustain and propel the “extreme complexity” of its living and intelligent inhabitants? Modern physics can be interpreted as having discovered that reality is made out of information (see “digital physics”)–if it is made out of anything at all. What is information? G. Bateson defined it as “a difference that makes a difference,” with the implication that it must make a difference to somebody. Information is the result of measurement, and you guessed it, minds are the only kinds of things we know of that can measure. So your first objection doesn’t seem to hold up. “Physical rules” are not mind-independent, but the result of the measurement of minds.
You suggest idealism is incoherent 2) for not explaining why minds become unconscious.
-If you’ll follow me in recognizing that there are both conscious and unconscious mental states, then it is quite simple for one of the idealist persuasion to explain why consciousness sometimes seems to disappear. When it does disappear, it is not therefore dissolved into nothingness, but enters the unconscious, which is still part of mind proper. The unconscious is full of feelings, images, instincts, and all sorts of proto-conscious contents. The idealist is not committed to the notion that mind is always conscious mind.
You suggest idealism is incoherent because 3) it doesn’t explain death: “why should the minds that we see be so dependent on the body?”
-The idealist could still be correct about the nature of reality, if, upon his or her own death, the mind continues to exist in some other form in a dimension invisible to those of us who remain physically embodied, watching the idealist’s body decompose. Your question forgets that the death of another person is not at all the same, ontologically, as my own death. What I can know about the latter 2nd hand is not the same as what I can know 1st hand about the former.
You suggest sensation is explained as an “extremely complex chemical reaction.”
-This is true, living things are extremely complex; but how, exactly, does this complexity of structure and molecular work become the conscious experience of agency, mental imagery, or the feeling of beauty? I’m not asking for an explanation of behavior that looks as if it were conscious. I am asking for an explanation, or at least a theoretical account, for the supposed causal mechanism that turns physical motions into conscious emotions. How does the exchange of electrons create intelligence? I am not disputing that, in some sense, this is exactly what is actually happening. My point is that matter must not be the kind of stuff the materialist assumes it is if consciousness is worth taking seriously (and not just dismissed as an illusion or epiphenomenon).
You suggest that materialism could be proven false, if only an idealist could demonstrate how mind could not be the result of material processes. But you’ve offered no theory for how matter (whose behavior is, I think you’d argue, purely mechanical) could make mind. The materialist is in no better position so far as demonstration goes.
Rationality of the kind known and practiced in Europe in the modern period shouldn’t be conflated with ancient traditions, whether they are Greek (Democritus) or Indian (Carvaka). Non-dual traditions like Madhyamaka are not analytical slouches, but their conclusions about the nature of reality are foreign to Western habits of mind. If we remain within our own categories, perhaps my arguments above about the superiority of idealism hold true. But I think Nargajuna’s dialectic successfully demolishes both materialism and idealism as independent systems. He reveals them to be ultimately self-contradictory (or mutually-dependent). All that is real, mental or physical, dependently co-originates. Idealism and materialism would then depend on an outer antagonism in order to maintain the semblance of their own inner consistency. I believe something similar holds true of atheism and theism.