Conscience is the inner perception of objections to definite wish impulses that exist in us; but the emphasis is put upon the fact that this rejection does not have to depend on anything else, that it is sure of itself. This becomes even plainer in the case of a guilty conscience, where we become aware of the inner condemnation of such acts which realized some of our definite wish impulses. Confirmation seems superfluous here; whoever has a conscience must feel in himself the justification of the condemnation, and the reproach for the accomplished action. But this same character is evinced by the attitude of savages towards taboo. Taboo is a command of conscience, the violation of which causes a terrible sense of guilt which is as self-evident as its origin is unknown[89]. It is therefore probable that conscience also originates on the basis of an ambivalent feeling from quite definite human relations which contain this ambivalence. It probably originates under conditions which are in force both for taboo and the compulsion neurosis, that is, one component of the two contrasting feelings is unconscious and is kept repressed by the compulsive domination of the other component. This is confirmed by many things which we have learned from our analysis of neurosis. In the first place the character of compulsion neurotics shows a predominant trait of painful conscientiousness which is a symptom of reaction against the temptation which lurks in the unconscious, and which develops into the highest degrees of guilty conscience as their illness grows worse. Indeed, one may venture the assertion that if the origin of guilty conscience could not be discovered through compulsion neurotic patients, there would be no prospect of ever discovering it. This task is successfully solved in the case of the individual neurotic, and we are confident of finding a similar solution in the case of races. In the second place we cannot help noticing that the sense of guilt contains much of the nature of anxiety; without hesitation it may be described as ‘conscience phobia’. But fear points to unconscious sources. The psychology of the neuroses taught us that when wish feelings undergo repression their libido becomes transformed into anxiety. In addition we must bear in mind that the sense of guilt also contains something unknown and unconscious, namely the motivation for the rejection. The character of anxiety in the sense of guilt corresponds to this unknown quantity.