The habit of walking is expressed in what a man sees when he keeps still, even in dreams. The recognition of distances and directions of things from his place at rest is the obvious proof of this statement. The habit of locomotion is latent in the sense that it is covered up, counteracted, by a habit of seeing which is definitely at the fore. But counteraction is not suppression. Locomotion is a potential energy, not in any metaphysical sense, but in the physical sense in which potential energy as well as kinetic has to be taken account of in any scientific description. Everything that a man who has the habit of locomotion does and thinks he does and thinks differently on that account. This fact is recognized in current psychology, but is falsified into an association of sensations. Were it not for the continued operation of all habits in every act, no such thing as character could exist. There would be simply a bundle, an untied bundle at that, of isolated acts. Character is the interpenetration of habits. If each habit existed in an insulated compartment and operated without affecting or being affected by others, character would not exist. That is, conduct would lack unity being only a juxtaposition of disconnected reactions to separated situations. But since environments overlap, since situations are continuous and those remote from one another contain like elements, a continuous modification of habits by one another is constantly going on. A man may give himself away in a look or a gesture. Character can be read through the medium of individual acts. Of course interpenetration is never total. It is most marked in what we call strong characters. Integration is an achievement rather than a datum. A weak, unstable, vacillating character is one in which different habits alternate with one another rather than embody one another. The strength, solidity of a habit is not its own possession but is due to reinforcement by the force of other habits which it absorbs into itself. Routine specialization always works against interpenetration. Men with "pigeon-hole" minds are not infrequent. Their diverse standards and methods of judgment for scientific, religious, political matters testify to isolated compartmental habits of action. Character that is unable to undergo successfully the strain of thought and effort required to bring competing tendencies into a unity, builds up barriers between different systems of likes and dislikes. The emotional stress incident to conflict is avoided not by readjustment but by effort at confinement. Yet the exception proves the rule. Such persons are successful in keeping different ways of reacting apart from one another in consciousness rather than in action. Their character is marked by stigmata resulting from this division.