Psychology. 553 
The animal machine is the most perfect converter of energy known, 
acting with far less waste than any apparatus of human invention. 
Every mental act involves conversion or metamorphosis of energy, 
whether it be a mere sensation or a memory, an emotion, ratiocina- 
tion or a determination of will. Throughout these processes the 
law of conservation of energy is necessarily obeyed. But mental 
acts possess qualities which require further attention in this connec- 
tion. Mind, as such, is not a form of energy. Reducing mind to 
its generalized expression,—that one which embraces all its phe- 
nomena,—viz., consciousness, it is safe to say that its qualities, and 
hence its definition, are totally distinct from those which we ascribe 
to, and by which we characterize energy. Energy is motion in one 
form or another. Consciousness is self-knowledge, from the sim- 
plest sensation upwards. No two subjects of thought can be more 
widely diverse. In fact, it is safe to say that all thinkable things are 
traceable to three sources ;—matter energy, or the motions of matter, 
and consciousness, or the knowledge which some matter has of itself. 
But I assumed at the outset of this paper, in common with most 
other persons, that designed acts are due to the direction and control 
of currents of energy exercised by conscious states. In this propo- 
sition there appears to be involved an assumption that in an act of 
will the law of the conservation of energy is violated. This, indeed, 
appears at first sight to be the state of the case; and it becomes 
necessary that we examine most fully into the process. It is not 
assumed that energy is created by an act of will, but it is supposed 
that energy is directed. The creation of energy is unthinkable. 
et us see whether the idea of its direction by some thing which is 
hot energy is a fact of experience or not. ieving, as I do, that 
consciousness, and hence will, isa phenomenon of a material tri- 
dimensional basis, and disclaiming the dualistic idea that conscious- 
n 
exercising control of the movements of such ia ieee basis. Having 
already expressed the belief that it does so, let us look into the 
lowing law. The ynamic expenditure of an act of will has no 
dynamic relation to the nature of the decision involved in it. 
This law may be illustrated as follows, in the case of the lower animals. 
An animal which is pursued by another may run into a hole or it 
may ascend a tree for safety. In the two cases totally different sets 
of muscles are used, The animal, for reasons, elects to use the one 
Set rather than the other set. Another animal may throw one ear 
forward to catch a sound rather than the other ear. Mechanisms 
