Dialectic, like love, has a good and a bad reputation. This ambivalence may be illustrated in different ways in almost every period of philosophical history. One may even suspect that this richness borders upon confusion. And yet, the attempt to orientate oneself in this jungle of meanings can be expected to be profitable, for the term “dialectic” has always referred, although often obscurely, to notions and processes of the first importance. The definition, illustration, and evaluation of the uses of this term should, accordingly, be a task promising some value.