That reflection terminates, through a definitive overt act,[3] in another non-reflectional situation, within which incompatible responses may again in time be aroused, and so another problem in reflection be set, goes without saying. Certain things about this situation, however, do not at the present time speak for themselves and need to be set forth. Let me in the first place call attention to an ambiguity in the term "knowledge." The statement that all knowledge involves reflection--or, more concretely, that it denotes an inference from evidence--gives offense to many; it seems a departure from fact as well as a wilful limitation of the word "knowledge." I have in this Introduction endeavored to mitigate the obnoxiousness of the doctrine by referring to "knowledge which is intellectual or logical in character." Lest this expression be regarded as a futile evasion of a real issue, I shall now be more explicit. (1) It may well be admitted that there is a real sense in which knowledge (as distinct from thinking or inquiring with a guess attached) does not come into existence till thinking has terminated in the experimental act which fulfils the specifications set forth in thinking. But what is also true is that the object thus determined is an object of _knowledge_ only because of the thinking which has preceded it and to which it sets a happy term. To run against a hard and painful stone is not of itself, I should say, an act of knowing; but if running into a hard and painful thing is an outcome predicted after inspection of data and elaboration of a hypothesis, then the hardness and the painful bruise which define the thing as a stone also constitute it emphatically an object of knowledge. In short, the object of knowledge in the strict sense is its objective; and this objective is not constituted till it is reached. Now this conclusion--as the word denotes--is thinking brought to a close, done with. If the reader does not find this statement satisfactory, he may, pending further discussion, at least recognize that the doctrine set forth has no difficulty in connecting knowledge with inference, and at the same time admitting that knowledge in the emphatic sense does not exist till inference has ceased. Seen from this point of view, so-called immediate knowledge or simple apprehension or acquaintance-knowledge represents a critical skill, a certainty of response which has accrued in consequence of reflection. A like sureness of footing apart from prior investigations and testings is found in instinct and habit. I do not deny that these may be better than knowing, but I see no reason for complicating an already too confused situation by giving them the name "knowledge" with its usual intellectual implications. From this point of view, the subject-matter of knowledge is precisely that which we do _not_ think of, or mentally refer to in any way, being that which is taken as matter of course,