CHAPTER IV.
THE COMPARATIVE METHOD AND LITERATURE.
§ 21. The comparative method of acquiring or communicating knowledge is in one sense as old as thought itself, in another the peculiar glory of our nineteenth century. All reason, all imagination, operate subjectively, and pass from man to man objectively, by aid of comparisons and differences. The most colourless proposition of the logician is either the assertion of a comparison, A is B, or the denial of a comparison, A is not B; and any student of Greek thought will remember how the confusion of this simple process by mistakes about the nature of the copula (ἐστι) produced a flood of so-called "essences" (οὐσίαι) which have done more to mislead both ancient and modern philosophy than can be easily estimated. But not only the colourless propositions of logic, even the highest and most brilliant flights of oratorical eloquence or poetic fancy are sustained by this rudimentary structure of comparison and difference, this primary scaffolding, as we may call it, of human thought. If sober experience works out scientific truths in propositions affirming or denying comparison, imagination even in the richest colours works under the same elementary forms. Athenian intellect and Alexandrian reflection failed to perceive this fundamental truth, and the failure
