THREE:In working out his theory of logic, the point on which Bacon lays most stress is the use of negative instances. He seems to think that their application to reasoning is an original discovery of his own. But, on examination, no more seems to be meant by it than that, before accepting any particular theory, we should consider what other explanations of the same fact might conceivably be offered. In other words, we should follow the example already set by Aristotle and nearly every other Greek philosopher after Socrates. But this is not induction; it is reasoning down from a disjunctive proposition, generally assumed without any close scrutiny, with the help of sundry conditional propositions, until we reach our conclusion by a sort of exhaustive process. Either this, that, or the other is the explanation of something. But if it were either that or the other, so and so would follow, which is impossible; therefore it must be this. No other logic is possible in the infancy of enquiry; but one great advantage of experiment and mathematical analysis is to relieve us from the necessity of employing it.Plato had, in truth, a conception of science which no knowledge then attainedperhaps one may add, no knowledge ever attainablecould completely satisfy. Even the rigour of mathematical demonstration did not content him, for mathematical truth itself rested on unproved assumptions, as we also, by the way, have lately discovered. Perhaps the Hegelian system would have fulfilled his requirements; perhaps not even that. Moreover, that the new order which he contemplated might be established, it was necessary to begin by making a clean sweep of all existing opinions. With the urbanity of an Athenian, the piety of a disciple, and the instinct of a great dramatic artist, he preferred to assume that this indispensable task had already been done by another. And of all preceding thinkers, who was so well qualified for the undertaking as Socrates? Who else had wielded the weapons of negative dialectic with such consummate dexterity? Who had assumed such a critical attitude towards the beliefs of his contemporaries? Who had been so anxious to find a point of attachment for every new truth in the minds of his interlocutors? Who therefore could, with such116 plausibility, be put forward in the guise of one who laid claim to no wisdom on his own account? The son of Phaenaret seemed made to be the Baptist of a Greek Messiah; but Plato, in treating him as such, has drawn a discreet veil over the whole positive side of his predecessors teaching, and to discover what this was we must place ourselves under the guidance of Xenophons more faithful report.
