looked from in certain ways, this position seems to stagger him.  The problem of existence reels and grows dim before him, and he fancies that he detects the presence of two Incomprehensibles, when he has really, in his state of mental insobriety, only seen one Incomprehensible double.  If this be not the case, it must be one that, intellectually, is even weaker than this.  It must be that, not of a man with a single coherent theory which his intellect in its less vigorous moments sometimes relaxes its hold upon, but it must be that of a man with two hostile theories which he vainly imagines to be one, and which he inculcates alternately, each with an equal emphasis.

If this bewilderment were peculiar to Dr. Tyndall, I should have no motive or meaning in thus dwelling on it.  But it is no peculiarity of his.  It is characteristic of the whole school he belongs to; it is inherent in our whole modern positivism—­the whole of our exact and enlightened thought.  I merely choose Dr. Tyndall as my example, not because there is more confusion in his mind than there is in that of his fellow-physicists, but because he is, as it were, the enfant terrible of his family, who publicly lets out the secrets which the others are more careful to conceal.

But I have not done with this matter yet.  We are here dealing with the central problem of things, and we must not leave it till we have made it as plain as possible.  I will therefore re-state it in terms of another metaphor.  Let us compare the universal matter, with its infinity of molecules, to a number of balls on a billiard-table, set in motion by the violent stroke of a cue.  The balls at once begin to strike each other and rebound from the cushions at all angles and in all directions, and assume with regard to each other positions of every kind.  At last six of them collide or cannon in a particular corner of the table, and thus group themselves so as to form a human brain; and their various changes thereafter, so long as the brain remains a brain, represent the various changes attendant on a man’s conscious life.  Now in this life let us take some moral crisis.  Let us suppose the low desire to cling to some pleasing or comforting superstition is contending with the heroic desire to face the naked truth at all costs.  The man in question is at first about to yield to the low desire.  For a time there is a painful struggle in him.  At last there is a sharp decisive pang; the heroic desire is the conqueror, the superstition is cast away, and ’though truth slay me,’ says the man, ‘yet will I trust in it.’  Such is the aspect of the question when approached from one side.  But what is it when approached from the other?  The six billiard balls have simply changed their places.  When they corresponded to low desire, they formed, let us say, an oval; when they corresponded to the heroic desire, they formed, let us say, a circle.  Now what is the cause and what the conditions of this