Page:Popular Science Monthly Volume 14.djvu/642

624 How are we to conceive of it? Given (in Aristotelian phrase) its ούσια, what is its ποιότης, its ποσότης, and the rest, which go to make up its idea? "Existence" is, after all, only one of our three necessary forms of thought: "Space" and "Time" are also necessary to our thinking. And it is in vain for pure logicians to put on papal airs, to forbid the question, to cry Non possumus, and to stifle all free thinking. It is useless to say: "We have already, with razors of the utmost fineness, split and resplit every emergent phenomenon; we have, by assiduous devotion to the one single and undisturbed function of analysis, examined every possible conception that man can form, and have discovered everywhere compound notions, ideas that are 'impure' and capable of further logical fissures: salvation is only possible by the confession that 'Something Is'; there rest and be thankful!" It is all of no avail. Naturam expellas furca —she is sure to return in armed revolt, and to demand, Who told thee that thou wast thus nakedly equipped? Reason is one thing; but imagination is also another. If analysis is a power of the human mind, so also is synthesis. If you can not think at all without using the one, neither can you without employing the other. Take, for instance, a process of the "purest" mathematics—"twice six is twelve"; you were taught that probably with an abacus, and the ghost of the abacus still lingers in your brain. "The square of the hypotenuse": you saw that once in a figured Euclid, and you learned thereby to form any number of similar mental figures for yourself. No: you may call the methods by which mankind think "impure," or attach to them any other derogatory epithet you please; but mankind will deride you for your pains, and will reply: "The philosopher who will only breathe pure oxygen will die; he that walks on one leg, and declines to use the other, will cut but a sorry figure in society; he that uses only one eye will never get a stereoscopic view of anything. Use, man, the compound instrument of knowledge your nature has provided for you, and you will both see and live." Why, even so determined a logician as "Physicus" is obliged sometimes to admit that "this symbolic method of reasoning is, from the nature of the case, the only method of scientific reasoning which is available." And Professor Tyndall, in the November number of another Review, after complaining that "it is against the mythologic scenery of religion that Science enters her protest," finds himself also obliged to mythologize; for he adds (seven pages further on): "How are we to figure this molecular motion? Suppose the leaves to be shaken from a birch-tree, . . . and, to fix the idea, suppose each leaf," etc. And so Professor Cooke writes:

I can not agree with those who regard the wave-theory of light as an established principle of science. . . . There is something concerned in the phenomena of light which has definite dimensions. We represent these dimensions to our