"Thirst for revenge is the most important source of ressentiment. As we have seen, the very term “ressentiment” indicates that we have to do with reactions which presuppose the previous apprehension of another person's state of mind. The desire for revenge—in contrast with all active and aggressive impulses, be they friendly or hostile—is also such a reactive impulse. It is always preceded by an attack or an injury. Yet it must be clearly distinguished from the impulse for reprisals or self-defense, even when this reaction is accompanied by anger, fury, or indignation. If an animal bites its attacker, this cannot be called “revenge.” Nor does an immediate reprisal against a box on the ear fall under this heading. Revenge is distinguished by two essential characteristics. First of all, the immediate reactive impulse, with the accompanying emotions of anger and rage, is temporarily or at least momentarily checked and restrained, and the response is consequently postponed to a later time and to a more suitable occasion (“just wait till next time”). This blockage is caused by the reflection that an immediate reaction would lead to defeat, and by a concomitant pronounced feeling of “inability” and “impotence.” Thus even revenge as such, based as it is upon an experience of impotence, is always primarily a matter of those who are “weak” in some respect. Furthermore, it is of the essence of revenge that it always contains the *consciousness* of “tit for tat,” so that it is never a mere emotional reaction."