Note 14 — THE CASUISTRY OF DUELLING.[13]

No terms of art are used so arbitrarily, and with such perfect levity, as the terms hypothesis, theory, system. Most writers use one or other with the same indifference that they use in constructing the title of a novel, or, suppose, of a pamphlet, where the phrase thoughts, or strictures, or considerations, upon so and so, are used ad libitum. Meantime, the distinctions are essential. That is properly an hypothesis where the question is about a cause: certain phenomena are known and given: the object is to place below these phenomena a basis [α ὑποθοσις] capable of supporting them, and accounting for them. Thus, if you were to assign a cause sufficient to account for the aurora borealis, that would be an hypothesis. But a theory, on the other hand, takes a multitude of facts all disjointed, or, at most, suspected, of some inter-dependency: these it takes and places under strict laws of relation to each other. But here there is no question of a cause. Finally, a system is the synthesis of a theory and an hypothesis: it states the relations as amongst an undigested mass, rudis indigestaque moles, of known phenomena; and it assigns a basis for the whole, as in an hypothesis. These distinctions would become vivid and convincing by the help of proper illustrations.