Abstract

Let _P_ represent the totality of the fundamental physical truths, and let _M_ represent the totality of non-fundamental physical truths. What is the relationship between P and M? In this paper, I argue for two related claims. The first, which I term the _inscrutability thesis_, is that there is no a priori entailment from P to M. This means that even a God-like intellect, given all the truths of P, could not deduce that M obtains without further a posteriori information. The second claim is that P alone is not metaphysically sufficient for M– or, to put it another way, that M does not supervene metaphysically on P. Rather, I argue, M supervenes on the combination of P with the totality of truths about phenomenal consciousness, represented as _Q_. I call this thesis _second-order idealism_. According to second-order idealism, if Q had been sufficiently different, then M would have been different– even if we hold P constant, and even assuming the mind-independence of P. Thus the higher-order structure of the physical world depends in part upon consciousness.