 A number of authors have looked to quantum mechanics to help explain consciousness and free will (e.g., Compton 1935; Eccles 1970; Penrose 1991, 1994 and 1997; Beck and Eccles 1992; Stapp 1993; Kane 1996;  quantum consciousness). Still it has been less clear to many that quantum mechanics is relevant to consciousness and free will. For example, an early objection to quantum effects influencing human volitions was offered by philosopher J. J. C. Smart (1963,   pp. 123–4).[15]  Even if indeterminism was true at the quantum level, Smart argued that the brain remains deterministic in its operations because quantum events are insignificant by comparison. After all a single neuron is known to be excited by on the order of a thousand molecules, each molecule consisting of ten to twenty atoms. Quantum effects though substantial when focusing on single atoms are presumed negligible when focusing on systems involving large numbers of molecules. So it looks like quantum effects would be too insignificant in comparison to the effects of thousands of molecules to play any possible role in consciousness or deliberation. 