all so from without, and vice versa. Yet it is difficult to draw any sharp line of demarcation between the two classes, and in the account which I shall give of suggestion I shall confine myself to the latter. I may have occasion to recur to suggestions from within in a later paper. I shall also limit myself to the discussion of the tendency to development and the associative and motor tendencies of mental states, omitting for the present their effects upon the metabolic processes. Thus the chief phenomena which I shall pass in review are, (1) the development of a suggested idea into a "sensory" hallucination, (2) the expansion of a suggested idea into a complete dream by evocation of associated ideas, (3) the production of bodily movements by means of suggested sensations or ideas.
As I have already said, it is not easy to observe that one is one's self suggestible. One's present consciousness contains at all times such a mass of subnascent, nascent, and vivid states that it is impossible to trace the effects of any one group, yet occasionally one can catch a state on the wing, as it were, and note its effects. Some years ago, I came home about ten o'clock one sunny morning, deeply absorbed in thought; of the latter part of my walk I had no clear memories, but I came to myself to find myself standing in the sunlight, holding a lighted match aloft in my right hand, apparently looking for a gasjet. I always carried in a certain pocket my keys and a matchbox; the sight of the door had prompted me to thrust my hand into my pocket, but I had no clear thought of the latchkey of which I was in search. Had I had, the mere fact that my hand happened to come in contact with the matchbox would have produced no result. As it was, the feeling of the matchbox found no obstacle to its working out its own results my hand closed on the box, withdrew and opened it, took out a match and struck it, and this organized motor series was wrecked merely by the physical impossibility of lighting a gasburner where there was none to light, and not by the interference of inconsistent mental elements. Such phenomena are familiar to us all, but we rarely take pains to analyze them in detail, otherwise the precisely similar phenomena of hypnotic suggestion would not excite so much astonishment.
A large proportion of our acts are thus suggested by sense-impressions. Another large proportion is under the direct control of thoughts almost as simple, but the guiding thought is often so faint and phantomlike that it escapes attention. I was sitting once in a railway train on my way to Philadelphia; in the corner in front of me was an umbrella. I lifted my right hand, extended it, then let it fall. When I say that "I" did this I am not speaking with precision. "I" was at the time occupied with an entirely different train of thought, and the lifting and drop-
