I. “We cannot know things in themselves; all our knowledge is subjective; it is confined to our own states and changes.” II. If this is so, then still more is what we name the “objective” only a state or change of us as subjective; it is a mere fiction of the mind so far as it is regarded as a “beyond” or thing in itself. III. Hence we _do_ know the objective; for the scepticism can only legitimately conclude that the objective which we do know is of a nature kindred with reason; and that by an _a priori_ necessity we can affirm that not only all knowable must have this nature, but also _all possible existence_ must. In this we discover that the mistake on the part of the sceptic consists in taking self-conscious intelligence as something one-sided or subjective, whereas it must be, according to its very definition, subject and object in one, and thus universal. The difficulty underlying this stage of consciousness is that the mind has not been cultivated to a clear separation of the imagination from the thinking. As Sir Wm. Hamilton remarks, (Metaphysics, p. 487,) “Vagueness and confusion are produced by the confounding of objects so different as the images of sense and the unpicturable notions of intelligence.” Indeed the great “law of the conditioned” so much boasted of by that philosopher himself and his disciples, vanishes at once when the mentioned confusion is avoided. Applied to space it results as follows: I.—_Thought of Space._ 1. Space, if finite, must be limited from without; 2. But such external limitations would require space to exist in; 3. And hence the supposed limits of space that were to make it finite do in fact _continue it_. It appears, therefore, that space is of such a nature that it can only end in, or be limited by _itself_ and thus is universally _continuous_ or _infinite_. II.—_Imagination of Space._ If the result attained by pure thought is correct, space is infinite, and if so, it cannot be imagined. If, however, it should be found possible to compass it by imagination, it must be conceded that there really is a contradiction in the intelligence. That the result of such an attempt coincides with our anticipations we have Hamilton’s testimony—“imagination sinks exhausted.” Therefore, instead of this result contradicting the first, as Hamilton supposes, it really confirms it.