Proof by testimony, which is available in connexion with questions of fact, is unavailable in connexion with general truths; and logical proof is obtainable only in that comparatively narrow sphere where reasoning is based—as in mathematics—upon axioms, or—as in certain really crucial experiments in the mathematic sciences—upon quasi-axiomatic premisses.
Everywhere else we base our reasonings on premisses which are simply more or less probable; and accordingly the conclusions which we arrive at have in them always an element of insecurity.
It will be clear that in philosophy, in jurisprudence, in political economy and sociology, and in literary criticism and such like, we are dealing not with certainties but with propositions which are, for literary convenience, invested with the garb of certainties.
What kind of logical sanction is it, then, which can attach to reasonings such as are to be set out here?
They have in point of fact the sanction which
