science, considered as to their relation to the general sum of human
knowledge, and their logical value as aids to its further progress. But
after all this, there remains a further and distinct question. We are
taught the right way of searching for results, but when a result has
been reached, how shall we know that it is true? How assure ourselves
that the process has been performed correctly, and that our premises,
whether consisting of generalities or of particular facts, really prove
the conclusion we have grounded on them? On this question M. Comte
throws no light. He supplies no test of proof. As regards deduction, he
neither recognises the syllogistic system of Aristotle and his
successors (the insufficiency of which is as evident as its utility is
real) nor proposes any other in lieu of it: and of induction he has no
canons whatever. He does not seem to admit the possibility of any
general criterion by which to decide whether a given inductive inference
is correct or not. Yet he does not, with Dr Whewell, regard an inductive
theory as proved if it accounts for the facts: on the contrary, he sets
himself in the strongest opposition to those scientific hypotheses
which, like the luminiferous ether, are not susceptible of direct proof,
and are accepted on the sole evidence of their aptitude for explaining
phenomena. He maintains that no hypothesis is legitimate unless it is
susceptible of verification, and that none ought to be accepted as true
unless it can be shown not only that it accords with the facts, but that
its falsehood would be inconsistent with them. He therefore needs a test
of inductive proof; and in assigning none, he seems to give up as
impracticable the main problem of Logic properly so called. At the
beginning of his treatise he speaks of a doctrine of Method, apart from
particular applications, as conceivable, but not needful: method,
according to him, is learnt only by seeing it in operation, and the
logic of a science can only usefully be taught through the science
itself. Towards the end of the work, he assumes a more decidedly