34 
be found in this as abundantly as in any other science.” The 
theories of thinkers like Reid and Stewart, Hamilton and Browne, 
were evolved from their inner consciousness, and were moulded 
entirely from introspection instead of from observation. They 
may be compared to the pre-Baconian philosophers: to the new 
school belong Gall and Spurzheim, George and Andrew Combe, 
Abercrombie and Moore, Carpenter, Spencer, Cox. Still, however, 
the question remains, Can a science be made of that which is 
imperceptible to the senses? The positivists would reply in the 
negative. Magnetism, electricity, and the law of gravitation are 
all in themselves imperceptible to the senses. Why do we believe 
in them? Because the existence of a thing can be proved by 
manifestation of effects of which it was the cause as well as the 
cognition of palpable substance. Of magnetism, of electricity, of 
gravitation we know no more than we can know of the soul and 
mind, but we believe in them because, although imperceptible 
themselves, we learn their nature and qualities by observing their 
manifestation upon matter that is perceptible. The nature and 
qualities of a mind, or soul, or pneuma must be studied in the same 
manner; and should we ever find instances in which a mind, or 
soul, or pneuma acts independently of the usual material agents— 
instances in which the effect of hearing is produced without the 
agency of the ears, the effect of seeing without the agency of the 
eyes—we are at least led towards the conclusion that a mind or 
soul may exist independent of the material structure of the body. 
Physiologists can find nothing in the human structure that is not 
material: all that the microscope and the scalpel reveal dies and 
is dissipated. Is there nothing more? Stones are structures, so 
are sponges; but man has intelligence, which a stone has not. 
What, then, is there in the structure of a man which there is not 
in the structure of a stone that gives intelligence to the man and 
not to the stone? To this important question various replies are 
made. I shall endeavour to give expression to the most prominent 
ones. 
First comes the ancient belief that the material structure of 
man is the shrine of an immortal soul destined to survive the 
