Conflicting Systems in the History of Philosophy. Hegel's logic consists, as is well known, in a chain of categories, connected by a relation of dialectic, which proceeded from the featureless Being, Nothing, and Becoming through more important ones such as Substance, Cause, and Reciprocity to the highest category of all, the Absolute Idea. Now Hegel also pointed to an interesting correlation between the categories of his logic and the dominant concepts of those philosophies that preceded his own: that is to say, the logical order of categories given by him corresponded to the temporal order of the history of philosophy. Such connexion was not, however, to be regarded as an accident but as a necessary truth: for the Absolute manifested itself temporally in the form of the history of philosophy. Seeing that this contention probably contains some psychological truth and is probably assumed in Marxian interpretations of Hegel, it may be of some interest to see how far it can be substantiated.