CONSCIOUSNESS AND THE WILL 67 



ness has its origin in the philosophy of Rene* Des- 

 cartes. The deep insight of Descartes convinced 

 him that matter was essentially quantitative or 

 spatial, capable of infinite subdivision and con- 

 trolled by mechanical laws. On the other hand, 

 mind or spiritual substance was teleological, indi- 

 visible, and qualitative. Matter and mind, therefore, 

 are realities utterly independent of each other. 

 Matter is nothing but quantitative; mind, nothing 

 but qualitative. This acceptance of dualism made 

 it necessary for people to abandon any conception 

 of a causal relation between these divided realms of 

 the universe matter and mind. But Descartes 

 and his followers teach that bodily conditions, as, 

 for example, the retinal changes under the action of 

 light, affect the mind with perception. And just 

 here lies the hopeless inconsistency of the Cartesian 

 doctrine; for if changes in the matter of the retina 

 really act on mind, how is this effect brought about 

 if matter and mind are distinct? True causality 

 implies a passage of energy from the causal agent to 

 the object in which the effect arises. But how can 

 energy be transferred from somewhere (as the retina) 

 to nowhere (the mind) ? We are forced to the view 

 that matter and mind either do not affect each 

 other in which case the retinal change could not 

 affect the mind, and God, being spiritual, could not 

 create material objects or there are not, in fact, 

 two entirely independent sets of reality. There are 

 many reasons why the mind of the biologist tends to 



