ABSTRACT
The first task before the libertarian is to break the neurophysiological determinist's argument to show, of any decision, that it had necessarily to occur. The libertarian, that is, will claim that not all neural events or states are completely determined by preceding physical states, that there is an element in the nervous system of real indeterminacy. Eccles calculates that there is an indeterminacy in the position of a synaptic vesicle of about fifty angstrom in one millisecond; now if the position of a vesicle is indeterminate, it is also indeterminate when it will reach the presynaptic membrane to release its chemical. This chapter examines two famous attempts to show that the mind is not dependent on the brain, at any rate, not utterly so. The first is J. R. Lucas's Godelian argument; the second, D. M. MacKay's idea of 'relativistic logic'.
