There are two very different classes of philosophical heads--which, since Kant has introduced into philosophy the idea of positive and negative quantities, I shall willingly classify by means of that distinction. The positive intellect is, like the poet, in conjunction with the outer world, the father of an inner world; and, like the poet also, holds up a transforming mirror in which the entangled and distorted members as they are seen in our actual experience enter into new combinations which compose a fair and luminous world: the hypothesis of Idealism (i. e. the FichtÉan system) the Monads and the Pre-established Harmony of Leibnitz--and Spinozism are all births of a genial moment, and not the wooden carving of logical toil. Such men therefore as Leibnitz, Plato, Herder, &c., I call positive intellects; because they seek and yield the positive; and because their inner world, having raised itself higher out of the water than in others, thereby overlooks a larger prospect of island and continents. A negative head, on the other hand, discovers by its acuteness--not any positive truths, but the negative (i. e. the errors) of other people. Such an intellect, as for example Bayle, one of the greatest of that class,--appraises the funds of others, rather than brings any fresh funds of his own. In lieu of the obscure ideas which he finds he gives us clear ones: but in this there is no positive accession to our knowledge; for all that the clear idea contains in development exists already by implication in the obscure idea. Negative intellects of every age are unanimous in their abhorrence of everything positive. Impulse, feeling, instinct--everything, in short, which is incomprehensible, they can endure just once--that is, at the summit of their chain of arguments as a sort of hook on which they may hang them,--but never afterwards.