ABSTRACT
N discussing mental structure and functions, we have likened the mind to a factory full of delicate machines, recognizing that the analogy is very imperfect. We said that just as the factory contains many machines, each a unit capable of performing some special operation, so the mind contains many functional units each of which we call a disposition. We distinguished dispositions of two principal classes; on the one hand, the various abilities, each of which is so constituted as to perform, when set in action, some special function; on the other hand, the propensities, which we likened to so many dynamos, each of which can generate energy and supply it to various abilities, thus activating them or bringing them into play.
