_Generally admitted._--The existence of ideas not directly furnished by sense or experience, and not given by the faculties whose office it is to deal with objects of sense, is a doctrine now generally admitted by the most eminent philosophers. Nor is it a doctrine peculiar to any one school. Under different names it is the doctrine substantially of Reid, Stewart, Brown, Price, among English metaphysicians; Kant and his disciples in Germany; Cousin, Jouffroy and others in France. It is denied by Hobbes, Condillac, Gassendi, and others of that class who trace all our ideas to sense as their ultimate source and parentage. _Opinion of Locke._--The position of Locke respecting this matter, has been the subject of much controversy. By a certain class of writers he has been regarded as denying the existence of any and all ideas not derived from sense, and has been classed with the school of Hobbes, Condillac, etc. His philosophy has been regarded by many as of doubtful and dangerous tendency, as leading to the denial of all truth and knowledge not within the narrow domain of sense, and so conducting to materialism and skepticism. This can by no means be fairly charged upon him, nor upon his philosophy. He held no such views, nor are they implied or contained in his doctrine. Locke, indeed, takes the ground that all our ideas may be traced ultimately to one of two sources, sensation or reflection; the one taking cognizance of external objects, the other of our own mental operations: and that, whatever other knowledge we have not given directly by these faculties, is produced by adding, repeating, and variously combining, in our own minds, the simple ideas derived from these sources. In this process, however, of adding, combining, etc., he really includes what we prefer to designate as a separate faculty of the mind, and by another name. He distinctly recognizes the existence of the ideas which we attribute to this faculty--ideas of space, power, etc.--and gives a clear, and for the most part correct account of their origin. The mind, he says, observes what passes without--the changes there occurring; it reflects also on what passes within--the changes of its own ideas and purposes; it concludes that like changes will be produced in the same things, under the same circumstances, in future; it considers the possibility of effecting such changes, and so comes by the idea of _power_. In this Locke really includes essentially what we mean by suggestion or original conception. Experience, it is universally admitted, furnishes the occasion, suggests the idea, must precede as the indispensable condition of the mind's having that idea, and is, at least in this sense, the source of it, that it suggests the idea to the mind. All this, Locke fully admits, while, at the same time, he fails to draw the dividing line clearly between the ideas of sense and those in question.