material movement, on the force or figure of which the thoughts and feelings are dependent.  Now if physical observations are to be the only things that guide us, one important fact will become at once evident.  Matter existed and fermented long before the evolution of mind; mind is not an exhibition of new forces, but the outcome of a special combination of old.  Mental facts are therefore essentially dependent on molecular facts; molecular facts are not dependent on mental.  They may seem to be so, but this is only seeming.  They are as much the outcome of molecular groupings and movements as the figures in a kaleidoscope are of the groupings and movements of the colored bits of glass.  They are things entirely by the way; and they can as little be considered links in any chain of causes as can the figure in a kaleidoscope be called the cause of the figure that succeeds it.

The conclusion, however, is so distasteful to most men, that but few of them can be brought even to face it, still less to accept it.  There is not a single physicist of eminence—­none at least who has spoken publicly on the moral aspects of life—­who has honestly and fairly considered it, and said plainly whether he accepts it, rejects it, or is in doubt about it.  On the contrary, instead of meeting this question, they all do their best to avoid it, and to hide it from themselves and others in a vague haze of mystery.  And there is a peculiarity in the nature of the subject that has made this task an easy one.  But the dust they have raised is not impenetrable, and can, with a little patience, be laid altogether.

The phenomenon of consciousness is in one way unique.  It is the only phenomenon with which science comes in contact, of which the scientific imagination cannot form a coherent picture.  It has a side, it is true, that we can picture well enough—­’the thrilling of the nerves,’ as Dr. Tyndall says, ’the discharging of the muscles, and all the subsequent changes of the organism.’  But of how these changes come to have another side, we can form no picture.  This, it is perfectly true, is a complete mystery.  And this mystery it is that our modern physicists seize on, and try to hide and lose in the shadow of it a conclusion which they admit that, in any other case, a rigorous logic would force on them.

The following is a typical example of the way in which they do this.  It is taken from Dr. Tyndall. ‘The mechanical philosopher, as such,’ he says, ’will never place a state of consciousness and a group of molecules in the position of mover and moved.  Observation proves them to interact; but in passing from one to the other, we meet a blank which the logic of deduction is unable to fill....  I lay bare unsparingly the initial difficulty of the materialist, and tell him that the facts of observation which he considers so simple are “almost as difficult to be seized as the idea of a soul.”  I go further, and say in effect:  “If you