NewThoughtLibrary.com / DivineLibrary.org

long do the senses ante-date in development the other intellectual powers? When these come, they come thus, not otherwise. The fact of co-existence is a mere blind datum of sensations, until contemplated under the idea of space. The (4) actual co-existence of two things is not involved in space, but only its possibility. The extension of space as the possibility of such a co-existence is the notion of space, is in and of the very idea. Actual co-existence alone rests on sensation, the possibility of it on the intuition. Mr. Spencer is not to think and speak of the coexistence of two positions as if it were identical with the co-existence of things. The first is in no way a datum of sensation. If he tries to make it so, he is thrown immediately back on to his former proof, and loses his present foothold.

We have made no distinction between extension and space. We regard the first only as a specification under the second. The extension of particular objects, and the duration of particular events, are forms under which the mind applies the intuitive ideas of space and of time. A knowledge of actual spaces, a measurement of material objects, are the fruits of experience; but these estimates proceed always under the prior notion of space, which makes them intelligible.

Space, in its analytical contemplation, furnishes a variety of intuitive conceptions which are the basis of the demonstrative reasonings of Geometry and Trigonometry. Such a notion is position, a line, a surface, perfect curves, figures, solids. A circle, in its accurate form as a ground of demonstrative truth, is an intuitive conception, as are the propositions which flow from the immutable relation of its parts, and of the lines which define, and are defined by them. A surface without thickness, a line without breadth, a point without dimensions, are all intuitive conceptions under the