Lastly, you should realise that in an organism so complicated as man, and of such varied and eventful history, _movement by itself is no index to mental process_. There are, no doubt, outward and visible signs of hesitation, of deliberation, of quick resolve; but the bare movement is not a cue to mind. Psychological enquiry must always go _behind_ the movement; that is, we must either know the previous mental history of the individual who makes the movement, or we must ourselves arrange the circumstances under which the movement is to be made. Suppose, for instance, that you have to sign your name to a deed. You may have spent weeks in reflection, in balancing pros and cons, in painful indecision; your action is then a ‘voluntary action’ of the most positive sort; and yet, when the moment comes, your signature flows smoothly from the pen, as if the matter had never cost you a moment’s worry. Now suppose that you are sitting in a committee-meeting, listening to a tedious report; you take the blank paper before you, and write your accustomed signature, without either the intention to write or knowledge that you are writing. The two movements may be indistinguishable, and yet this second writing is an ‘automatic’ or ‘involuntary’ action. So a hand-shake may mean the barest recognition of a casual acquaintance, or the friendly settlement of a long-standing disagreement; the onlooker can see no difference in the movements, though their mental accompaniments are worlds apart. There is, indeed, no chapter in psychology that illustrates _the law of mental growth and decay_ (p. 183) so fully and so surprisingly as this chapter on action. Movements that once were rich in mental correlates fall into the direst psychological poverty; and movements that now are poor may acquire a mental fortune, which they in their turn are bound presently to lose. § 54. =The Typical Action.=—Under these circumstances, it sounds a little incongruous to talk of a ‘typical’ action. But we must start somewhere; and we may, perhaps, say that the typical action, for psychology, is _an action of the simplest form taken at its psychological best_; in other words, an organic movement that is _singly_ determined and that shows a _maximum_ of mental accompaniment. You will understand better what this definition means when we have worked out an illustration. Meantime, you can see that such an action—we call it an =impulsive= action—serves as point of departure in two directions. The form may remain simple, while the mental side suffers reduction; or the form may become complicated, and therewith new mental characters may be introduced. In the former case, the impulsive action runs downhill toward automatic; in the latter, it climbs up toward deliberative action.