It will now be understood that Logic is the all-animating spirit of all the sciences, and its categories the spiritual hierarchy. They are the heart and centre of things: and yet at the same time they are always on our lips, and, apparently at least, perfectly familiar objects. But things thus familiar are usually the greatest strangers. Being, for example, is a category of pure thought: but to make 'Is' an object of investigation never occurs to us. Common fancy puts the Absolute far away in a world beyond. The Absolute is rather directly before us, so present that so long as we think, we must, though without express consciousness of it, always carry it with us and always use it. Language is the main depository of these types of thought; and one use of the grammatical instruction which children receive is unconsciously to turn their attention to distinctions of thought. Logic is usually said to be concerned with forms _only_ and to derive the material for them from elsewhere. But this 'only,' which assumes that the logical thoughts are nothing in comparison with the rest of the contents, is not the word to use about forms which are the absolutely-real ground of everything. Everything else rather is an 'only' compared with these thoughts. To make such abstract forms a problem pre-supposes in the inquirer a higher level of culture than ordinary; and to study them in themselves and for their own sake signifies in addition that these thought-types must be deduced out of thought itself, and their truth or reality examined by the light of their own laws. We do not assume them as data from without, and then define them or exhibit their value and authority by comparing them with the shape they take in our minds. If we thus acted, we should proceed from observation and experience, and should, for instance, say we habitually employ the term 'force' in such a case, and such a meaning. A definition like that would be called correct, if it agreed with the conception of its object present in our ordinary state of mind. The defect of this empirical method is that a notion is not defined as it is in and for itself, but in terms of something assumed, which is then used as a criterion and standard of correctness. No such test need be applied: we have merely to let the thought-forms follow the impulse of their own organic life.