It is a great step, when we have detected the Relativity of what had hitherto seemed Absolute,--when a new aspect of the infinite fullness of the world, the truth of things, dawns upon us. But it is even a greater step when we see that the Relativity which we have thus discovered is itself Relative. And this is one advantage of first studying the value of the categories of ethics and physics on Logical ground. On the concreter region of Nature and Mind, the several grades and species into which reality is divided have a portentous firmness and grandeur about them, and the intrinsic dialectic seems scarcely adequate to shaking the foundations of their stability. They severally stand as independent self-sustaining entities, separate from each other, and stereotyped in their several formations. But in the ether of abstract Idea, in the fluid and transparent form of mere thoughts, the several stages in the development of the Absolute, the various grades of category, clearly betray their Relativity, and by the negation of this Relativity lead on to a higher Absolute. To the practical man,--so long as his reflection does not go deep,--the concepts on which his knowledge and faith are built seem eternal, unshifting rock, parts of the inmost fabric of things. He accepts them as ultimate validities. To him matter and force, cause and effect, distinctions between form and content, whole and part, quantity and quality, belong to the final constitution of the world. (And so, in a sense, they do.) If he ever overcome the absoluteness which popular thought attributes to the individual things of sense and imagination, and show their relativity, he does so only to fall under the glamour of a new deception. Causes and matters, forces and atoms, become new ultimates, new absolutes, of another order. Fictions or postulates of the understanding take the place of the figments of imagination. The ordinary scientific man labours especially under the 'metaphysical' fallacy: he realises abstractions in their abstractness. As against this it is the business of the logician to show how such terms are to be interpreted as steps in a process of interpretation--containing so much that others of simpler structure have handed on, and themselves presupposing by implication a great deal they fail properly to explicate. Thus, the logician evinces at one blow the relativity of each term in its mereness, abstractness, or false absoluteness, and the ideal absoluteness which always carries it beyond itself, and makes it mean more than it says.