Microphysicalism without contingent micro-macro laws
In 'A Definition of Physicalism' [6], I sought to avoid an old dilemma for physicalism to which Tim Crane and Hugh Mellor [3] have recently given their support. Physicalism says, in their words, that the empirical world 'contains just what a true complete physics would say it contains'. The alleged dilemma is that physicalism is obviously false if 'physics' means 'actual physics', and that it is trivially true if it means 'ideal physics'. I argued that if we see the world as layered in different levels of composition, and if we identify the microphysical realm with the realm of subatomic (or whatever) levels, then we can define physicalism quite straightforwardly. Physicalism better, perhaps, microphysicalism is the doctrine that actually (but not necessarily) everything non-microphysical is composed out of microphysical entities and is governed by microphysical laws: and this, in a sense which means that the non-microphysical facts supervene contingently on the microphysical; more on supervenience later. Such a microphysicalist approach has no truck with talk of ideal physics and it only requires us to believe that actual physics is on track in postulating a microphysical realm, not in any matters of detail. On the face of it, the approach sails right through the horns of the dilemma. In a reply to my paper, Tim Crane [2] does not discuss this apparent capacity of the microphysicalist strategy to avoid the older dilemma. But he directs attention to a different challenge, and one that he may well consider more important.' He suggests that 'if the macro and micro levels are systematically connected' systematically but contingently connected, as in the microphysicalist picture 'then the connections between them