A Phtjsicist on Evolufwn. 197 



which we can never know.* In fact the whole process of evolution 

 is the manifestation of a Power absolutely inscrutable to the intellect 

 of man. As Httle in our day as in the days of Job can man by 

 searching find this Power out. Considered fundamentally, it is by 

 the operation of an insoluble mystery that life is evolved, species 

 diflferentiated, and mind unfolded from their prepotent elements in 

 the immeasurable past. There is, you will observe, no very rank 

 materialism here. 



The strength of the doctrine of evolution consists, not in an 

 experimental demonstration (for the subject is hardly accessible to 

 this mode of proof), but in its general harmony with the method of 

 nature as hitherto known. From contrast, moreover, it derives 

 enormous relative strength. On the one side we have a theory (if 

 it could with any propriety be so called) derived, as were the 

 theories referred to at the beginning of this address, not from the 

 study of nature, but from the observation of men — a theory which 

 converts the Power whose garment is seen in the visible universe 

 into an Artificer, fashioned after the human model, and acting by 

 broken efforts as man is seen to act. On the other side we have 

 the conception that all we see around us, and all we feel within us 

 — the phenomena of physical nature as well as those of the human 

 mind — have their unsearchable roots in a cosmical life, if I dare 

 apply the term, an infinitesimal span of which only is offered to 

 the investigation of man. And even this span is only knowable in 

 part. We can trace the development of a nervous system, and 

 correlate with it the parallel phenomena of sensation and thought. 

 We see with undoubting certainty that they go hand in hand. But 

 we try to soar in a vacuum the moment we seek to comprehend the 

 connection between them. An Archimedean fulcrum is here required 

 which the human mind cannot command; and the effort to solve 

 the problem, to borrow an illustration from an illustrious friend of 

 mine, is like the effort of a man trying to lift himself by his own 

 waistband. All that has been here said is to be taken in connection 

 with this fundamental truth. When " nascent senses " are spoken 

 of, when " the differentiation of a tissue at first vaguely sensitive all 



* In a paper, at onne popular and protbuncl, entitled " Recent Progi-ess in the 

 Theory of Vision," contained in the volume of letters by Hehnlioltz, published by 

 Longmans, this symbolism of our states of consciousness is also dwelt upon. The 

 impressions of sense are the mere siijns of external things. In this paper Helm- 

 holtz contends strongly against the view that tlie consciousness of space is inborn ; 

 and he evidently doubts the power of tlie chick to pick up grains of coin without 

 some preliminary lessons. On this point, he says, further expeiiments are needed. 

 Such experiments have been since made by Mr. Spalding, aided, I believe, in some 

 of his observations by the accomplished and deeply-lamented Lady Amberley ; and 

 they seem to prove conclusively that the chick does not need a single moment's 

 tuition to teach it to stand, run, govern the muscles of its eyes, and peck. Helm- 

 holtz, however, is contending against the notion of pre-established harmony; 

 and I am not aware of his views as to the organization of experiences of race 

 or breed. 



p 2 



