'_I should enquire after its shape_,' he says:--'_Has it legs or arms?
If not, I would wish it to be made clear to me how a thing without these appliances can act so perfectly the part of a builder ?_ He challenged the theist (the theist addressed at the time was Dr.Martineau) to give him some account of his God's workings; and '_When he does this_,' said Dr.Tyndall, '_I shall "demand of him an immediate exercise" of the power "of definite mental presentation."_' If he fails here, Dr.Tyndall argues, his case is at once disproved; for nothing exists that is not thus presentable.

Let us compare this with his dealing with the fact of consciousness.

Consciousness, he admits, is not thus presentable; and yet consciousness, he admits, exists.
Instances might be multiplied of the same vacillation and confusion of thought--the same feminine inability to be constant to one train of reasoning.

But those just given suffice.

What weight can we attach to a man's philosophy, who after telling us that consciousness may possibly be an inherent property of matter, of which '_the receit of reason is a limbec only_,' adds in the same breath almost, that matter generally is certainly not conscious, and that consciousness comes to the brain we know not whence nor wherefore?
What shall we say of a man who in one sentence tells us that it is impossible that science can ever solve the riddle of things, and tells us in the next sentence that it is doubtful if this impossibility will be accomplished within the next fifty years ?--who argues that God is a mystery, and therefore God is a fiction; who admits that consciousness is a fact, and yet proclaims that it is a mystery; and who says that the fact of matter producing consciousness being a mystery, proves the mystery of consciousness acting on matter to be a fact?
[36] It is true that one of the favourite teachings of the positive school is, that as to this question the proper attitude is that of Agnosticism; in other words, that a state of perpetual suspense on this subject is the only rational one.