The “conscience” of our moralizing and religious literature figures as a sharply defined and easily recognizable “faculty,” like “will” or “reason.”  But this classification, though useful, is misleading by its simplicity.  If we observe by introspection what goes on in our minds when we “will” or “reason” or “listen to conscience,” we shall find all sorts of emotions, ideas, impulses, surging back and forth, altering from moment to moment, never twice the same.  At another period of our lives, or in another man’s mind, the psychological stuff pigeonholed under these names may be almost entirely different.  A great many diverse mental elements have at one time or other taken the role of, or formed an ingredient in, the function we label “conscience.”  We will enumerate the more important: 

(1) Experience quickly teaches her pupils that certain acts to which they feel a strong impulse will lead to an aftermath of pain or weariness, or will stand in the way of other goods which they more lastingly desire or more deeply need.  The memory of these consequences of acts remains as a guide for future conduct, not so often in the form of a clearly recognized memory as in a dim realization that the dangerous act must be avoided, a vague pressure against the pull of momentary inclination, or an uncomprehended feeling of impulsion toward the less inviting path.  This residuum of the moral experience of the individual is one ingredient in what we call his conscience.

(2) But there is much more than this.  The individual is a member of a group.  The customs and expectations of this group not only bear upon him from without but find a reflection in his own motor mechanism.  He hears the voice of the community in his heart, an echo of the general condemnation and approval.  This acquired response, the reverberation of the group judgment, may easily supplant his personal inclinations.  Primitive man is sensitive to the judgments and emotional reactions of his fellows; the tribal point of view is unquestioned and authoritative over him.  So important is this pressure in his mental life, though not understood or recognized for what it is, that conscience is denned by many moralists as the pressure of the judgment of the tribe in the mental life of its members, or in similar terms.  Paulsen calls it “the existence of custom in the consciousness of the individual.”  This is to neglect unjustly the other sources of the sense of duty; but certainly the pulls and pushes arising from these two sources, which we may call the inner aspect of individual moral experience and of loyalty to the community-morals, reinforcing one another as they generally do, produce a very powerful form of conscience.