With this interest, in the Biographia Literaria, he refines Schelling's "Philosophy of Nature" into a theory of art. "There can be no plagiarism in philosophy," says Heine:--Es giebt kein Plagiat in der Philosophie, in reference to the charge brought against Schelling of unacknowledged borrowing from Bruno; and certainly that which is common to Coleridge and Schelling and Bruno alike is of far earlier origin than any of them. Schellingism, the "Philosophy of Nature," is indeed a constant tradition in the history of thought: it embodies a permanent type of the speculative temper. That mode of conceiving nature as a mirror or reflex of the intelligence of man may be traced up to the first beginnings of Greek speculation. There are two ways of envisaging those aspects of nature which seem to bear the impress of reason or intelligence. There is the deist's way, which regards them merely as marks of design, which separates the informing mind from its result in nature, as the mechanist from the machine; and there is the pantheistic way, which identifies the two, which [76] regards nature itself as the living energy of an intelligence of the same kind as though vaster in scope than the human. Partly through the influence of mythology, the Greek mind became early possessed with the conception of nature as living, thinking, almost speaking to the mind of man. This unfixed poetical prepossession, reduced to an abstract form, petrified into an idea, is the force which gives unity of aim to Greek philosophy. Little by little, it works out the substance of the Hegelian formula: "Whatever is, is according to reason: whatever is according to reason, that is." Experience, which has gradually saddened the earth's colours for us, stiffened its motions, withdrawn from it some blithe and debonair presence, has quite changed the character of the science of nature, as we understand it. The "positive" method, in truth, makes very little account of marks of intelligence in nature: in its wider view of phenomena, it sees that those instances are a minority, and may rank as happy coincidences: it absorbs them in the larger conception of universal mechanical law. But the suspicion of a mind latent in nature, struggling for release, and intercourse with the intellect of man through true ideas, has never ceased to haunt a certain class of minds. Started again and again in successive periods by enthusiasts on the antique pattern, in each case the thought may have seemed paler and more fantastic amid the growing [77] consistency and sharpness of outline of other and more positive forms of knowledge. Still, wherever the speculative instinct has been united with a certain poetic inwardness of temperament, as in Bruno, in Schelling, there that old Greek conception, like some seed floating in the air, has taken root and sprung up anew. Coleridge, thrust inward upon himself, driven from "life in thought and sensation" to life in