A very obvious criticism of number one is in affirming a consciousness of an "Unknowable," its quality of unknowableness is annihilated. Existence can only be predicated of that which affects consciousness in some manner; and so far as I have the slightest apprehension or consciousness of anything existing, to that extent it ceases to be the unknowable. Our knowledge of it may be imperfect or altogether erroneous; we may feel it impossible that we should ever rightly understand it; but so far as we think about it we are bound to assimilate it to the best of our knowledge, even though it be only under the category of force. In brief, "unknowableness" is not a property or quality by which a thing may be apprehended; it is a name for complete mental vacuity. It does not refer to the thing itself, it refers only to us. It is a pure negation which Spencer, by sheer verbal play converts into a quasi-positive conception. A consciousness of things unknown can never be more than a consciousness of ignorance. There is only one way to prove the existence of an unknowable, and that is to know nothing about it--not even to know that there is something about which we know nothing. But, says Spencer, "to say that we cannot know the absolute is, by implication, to affirm that there is an absolute." Certainly, if we take an infirmity of language to be the equivalent of a necessity of existence, not otherwise. When I say that we cannot know a four-sided triangle I do not affirm by implication that a four-sided triangle exists. I am asserting that the phrase, a four-sided triangle, involves conceptions that cannot be brought together in consciousness, and so dismiss it as being without meaning. The truth is that every one of Spencer's attempts to prove the existence of an unknowable turns out on examination to be no more than a proof of the existence of an unknown, and this is not disputed at any time or by anyone. Thus, after being told that a known cannot be thought of apart from an unknown, we are informed:-- Positive knowledge does not, and never can, fill the whole region of possible thought. At the utmost reach of discovery there arises, and must ever arise, the question, What lies beyond? As it is impossible to think of a limit to space so as to exclude the idea of space lying outside that limit, so we cannot conceive of any explanation profound enough to exclude the question, What is the explanation of the explanation?