BRUCE GLYMOUR, MARCELO SABATÉS and ANDREW WAYNE QUANTUM JAVA: THE UPWARDS PERCOLATION OF QUANTUM INDETERMINACY

Despite a general, if often provisional, acceptance of quantum indeterminacy, and a now orthodox physicalism on which macroscopic states are held to depend in some sense on microscopic states, many philosophers of mind and of science continue to work under the assumption that macro states, such as brain states, evolve deterministically from prior macro states. Frequently this presumption is implicit and undefended, or explicit but given minimal defense.1 In neither case is the tension between quantum indeterminacy, macro-micro dependence and macro determinism given full recognition. Sometimes the tension is recognized, but it is held that there is at least a legitimate hope that quantum indeterminism need not percolate up to the macro level.2 Finally, some philosophers of mind address the issue and defend the view that, for one reason or another, quantum indeterminacy not only need not, but in fact does not, percolate to the macro level.3 In this paper we demonstrate that micro indeterminism leads to macro indeterminism unless macro states are effectively independent from micro states. We show this is so whether the relationship between realizing and realized states is, in orthodox fashion, deterministic, or, in unorthodox fashion, indeterministic. The price of macroscopic determinism is that one must give up the dependence of the macro on the micro, a dependence upon which physicalism rests. A puzzle about the very idea of macroscopic determinism must be addressed at the outset. Macro determinism is an example of what is sometimes called partial determinism (Earman, 1986). We call a system partially deterministic with respect to a class of its properties just in case the state of the system at any particular time with regard