Anaxagoras, then, at least on this side of his teaching, must be considered rather as the author of a phrase than as the founder of a philosophy. The phrase remained, and had a profound influence on subsequent philosophies, but in his own hands it was little more than a dead letter. His immediate interest was rather in the variety of phenomena than in their conceived principle of unity; he is theoretically, perhaps, 'on the side of the angels,' in practice he is a materialist. [12] Mind he conceived as something apart, sitting throned like Zeus upon the heights, giving doubtless the first impulse to the movement of things, but leaving them for the rest to their own inherent tendencies. As distinguished from them it was, he conceived, the one thing which was absolutely pure and unmixed. All things else had intermixture with every other, the mixtures increasing in complexity towards the centre of things. On the outmost verge were distributed the finest and least complex forms of things--the sun, the moon, the stars; the more dense gathering together, to form as it were in the centre of the vortex, the earth and its manifold existences. By the intermixture of air and earth and water, containing in themselves the infinitely varied seeds of things, plants and animals were {56} developed. The seeds themselves are too minute to be apprehended by the senses, but we can divine their character by the various characters of the visible things themselves, each of these having a necessary correspondence with the nature of the seeds from which they respectively were formed. [128] Thus for a true apprehension of things sensation and reason are both necessary--sensation to certify to the apparent characters of objects, reason to pass from these to the nature of the invisible seeds or atoms which cause those characters. Taken by themselves our sensations are false, inasmuch as they give us only combined impressions, yet they are a necessary stage towards the truth, as providing the materials which reason must separate into their real elements.