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 ties, which must be assumed in all knowledge. His doctrine is formed by means of a reflex attention to that common sense which is spontaneously exercised by the many. Kant, assuming the famous test of necessity as the basis of his critical investigation, demonstrated the originality of many of those notions which Hume had rendered up as the illusions of a universe of mere phenomena. He thus exhibited a theory of subjective knowledge, seemingly self-consistent and permanent; while Reid exhibited those beliefs which are the security, if not the explanation, of all knowledge, subjective and objective. Both supplemented Locke. The “Essay concerning Human Understanding” had furnished an important analysis of what is contributed to our knowledge by experience, marked by the freshness of an independent thinker, who subjects old assumptions to a renewed act of careful observation. But in his desire to find, by means of induction, the limits within which the human mind may be advantageously occupied, Locke had omitted to examine critically the original structure of intellect that is implied in the ability to gain such experimental knowledge as he had noted and analyzed in his survey of the mind and its stores. The schools of Reid and Kant have given the prominence, which Locke neglected to assign, to this object of investigation in the prosecution of the theory of knowledge. The common sense of Reid is the object of Scottish inductive investigation; the categories of Kant of German formal criticism.

The philosophy of Sir William Hamilton is to a large