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240 but likewise by his clearer insight into the necessity of forming hypothesis and by the interchange of induction and deduction. The deductive method becomes necessary especially in cases where there are large numbers of contributing factors. We must then examine each factor separately by induction and then test by deduction from the results of these separate investigations whether the interplay of all the factors is explainable.

The final analysis of thought reveals the psychological basis of Mill's logic. According to Mill every deduction presupposes an induction. For—in his opinion—deduction starts from a general proposition; but whence can this proposition be derived, if not from experience? Every general proposition implies a reference to a number of experiences. We ultimately come back to the particular impressions. The beginning of the whole knowledge-process consists in the fact that two phenomena take place coincidently. Once this has happened frequently, the presence of the one phenomenon will arouse an expectation of the other. This is the fundamental form of inference. It does not however start from a general proposition, but rather proceeds from particulars to particulars. The child withdraws its hand from the burning taper, not because of its knowledge of the general proposition, that contact with fire is painful, but because the sight of fire immediately arouses the idea of pain. It is therefore an objective association (association by contact) that forms the original basis of all inference: all logical principles are eliminated. The transition from one idea to another takes place immediately, and, according to Mill, this means, without ground.—In the theory of causality Mill would likewise eliminate all presuppositions. Mill concedes however that the inductive methods