[Sidenote: The _understood_ as the unconsciously assumed] It is significant that one meaning of the term _understood_ is something so thoroughly mastered, so completely agreed upon, as to be _assumed_; that is to say, taken as a matter of course without explicit statement. The familiar "goes without saying" means "it is understood." If two persons can converse intelligently with each other, it is because a common experience supplies a background of mutual understanding upon which their respective remarks are projected. To dig up and to formulate this common background would be imbecile; it is "understood"; that is, it is silently supplied and implied as the taken-for-granted medium of intelligent exchange of ideas. [Sidenote: Inquiry as conscious formulation] If, however, the two persons find themselves at cross-purposes, it is necessary to dig up and compare the presuppositions, the implied context, on the basis of which each is speaking. The implicit is made explicit; what was unconsciously assumed is exposed to the light of conscious day. In this way, the root of the misunderstanding is removed. Some such rhythm of the unconscious and the conscious is involved in all fruitful thinking. A person in pursuing a consecutive train of thoughts takes some system of ideas for granted (which accordingly he leaves unexpressed, "unconscious") as surely as he does in conversing with others. Some context, some situation, some controlling purpose dominates his explicit ideas so thoroughly that it does not need to be consciously formulated and expounded. Explicit thinking goes on within the limits of what is implied or understood. Yet the fact that reflection originates in a problem makes it necessary _at some points_ consciously to inspect and examine this familiar background. We have to turn upon some unconscious assumption and make it explicit. [Sidenote: Rules cannot be given for attaining a balance]