There are just two possible ways of analyzing things. One way is to set the world with its particulars before the eye, look at it, and accept what we see. Then we may go to work on phenomena, dissecting and generalizing. This is the way of physics--a road that _never_ leads to _meta_-physics. It is the common turnpike of material science--of "positivism." In it travel all such men, say, as Dr. Ernst Hæckel: also all such men as the late Parson John Jasper, the colored preacher of Virginia, who, seeing the sun move round the earth, settled the fact in that way. The one other way of dissecting the universe is to examine the _means_ through which things are presented to us, and thus to ascertain what effect the means may have in the production and nature of the things. This method of investigation has ultimated in what has been summed up as "Scientific Idealism." Scientific idealism is the knowledge which every one may get even from his first lessons in optics, that things of matter--the objects of our five senses--are constituted such through the structure and action of these senses themselves. That is to say, material things--whatever we see or feel, hear, taste or smell--while existent and real--while practically what every one takes them to be--are _made so_ through _relativity_. Or, as Kant put it, every "phenomenon"--meaning every object or fact of sensation--is a "_re_-presentation"; that is, some lot of effects on our sensuous nature, bound together into a unity of them, the unity thus formed becoming an object of awareness, a "percept." Scientific idealism does not question the given duality of the cosmos, which appears to us as what we call "mind and matter." Here are _we_; out there, indubitably apart from us, are other things, involving another source. But scientific idealism has found that this source is itself quite other than the things we connect with it, and can properly be described in this connection only as _source of impact_. It has nothing to do with matter, in the common acceptation. It enters _into_ matter, being the ultimate non-ego, the objective background, of every phenomenon. But, in all material things, this background is _transformed_ by contact with subjective sense (in us or other organisms), and "matter" is really the fusion, the compound, the third term, of these two elemental principles. This momentous truth, though mystically reached in the old tenet of India that "matter is illusion," and though touched understandingly by Carneades in Greece, was first clearly seen, in the manner of modern science, by the remarkably solid Englishman, Thomas Hobbes.