MODERN THOUGHT 151 



and externalization, or the expansion and growth of mind, it would 

 seem almost as if the existence of mind were assumed. At any rate, its 

 existence is not absolutely denied or made identical with matter. 



There are scientists who think of mind as they think of matter, and 

 therefore study its operations as if it were the product of physical 

 forces alone. They are not surprised at the conclusions of Cabanis 

 that thought is a product of the brain as organized matter. These con- 

 clusions seem to them the logical outcome of Locke's theory of knowl- 

 edge and of the philosophy taught by the Frenchmen Abbe Condillac 

 and Helvetius. To them there seems to be no good reason why phrenol- 

 ogy should not be able to locate the different powers of the brain, as 

 Gall and Spurzheim tried to do at the beginning of the last century, 

 even if no attempt were made to account for the existence of that some- 

 thing called mind which makes use of the brain. 



However close we admit the relations to be between mind and matter, 

 however fully we may believe in the influence of the physical upon the 

 mental machine in man, it is well-nigh impossible to escape the con- 

 viction that mind and matter are diverse in their nature, that even if 

 mind makes use of matter in its operations and is aided by it so that 

 mind and matter may properly be studied together as a new science, 

 they are not thereby made one and the same thing. There are many 

 tvho still look upon physiology and psychology as different sciences, and 

 while recognizing their close relationship and welcoming the results of 

 studies and experiments in the border land between the two, they still 

 feel as if there were a science of mind which demands other experi- 

 ments and studies than those which physiology is able to furnish. 

 Nevertheless, it is certain that in all future studies of mental philos- 

 ophy the physical nature of man will be taken into account. 



From this brief review of theories concerning the universe, its origin 

 and meaning, each of which has been prominent in its turn, each of 

 which indicates a different point of view on the part of its defenders, 

 and each of which has in it a great deal of truth, it is clear that no one 

 of them can now be accepted as completely satisfactory or as covering all 

 the problems which meet us in trying to explain the universe. Taken 

 together, they disclose and give a reason for many of the processes of 

 nature, but they do not explain them all. Indeed, with every new dis- 

 covery new vistas open, new questions arise, new difficulties are to be 

 met. "VYe may, therefore, content ourselves by accepting that as true 

 which is proved to be true by all the theories. The fact of gravitation 

 is undeniable, even if the astronomical theory is no longer received as 

 adequate. Although no one has ever yet seen an atom, sound reason- 

 ing seems to require us to admit the existence of atoms and justifies us 

 in appealing to mathematics to prescribe the laws of an atomic world. 

 iSTor can we deny the evidences of universal motion, or that the kinetic 

 theory has a good basis upon which to stand. Equally evident is it 



