ADDRESa, ■ 9 



Tyndall's views as a strenuous supporter and believer in the theory of 

 evolution were naturally essentially optimistic. He had no sympathy 

 with the lugubrious pessimistic philosophy whose disciples are for ever 

 intent on administering rebuke to scientific workers by reminding them 

 that, however much knowledge man may have acquired, it is as nothing 

 compared witli the immensity of his ignorance. That truth is indeed 

 never adequately realised except by the man of science, to whom it is 

 brought home by repeated experience of the fact that his most promising 

 excursions into the unknown are invariably terminated by barriers which, 

 for the time at least, are insurmountable. He who has never made such 

 excursions with patient labour may indeed prattle about the vastness of 

 the unknown, but he does so without real sincerity or intimate conviction. 

 His tacit, if not his avowed, contention is, that since we can never know 

 all it is not worth while to seek to know more ; and that in the profundity 

 of his ignorance he has the right to people the unexplored spaces with the 

 phantoms of his vain imagining. The man of science, on the contrary, 

 finds in the extent of his ignorance a perpetual incentive to further 

 exertion, and in the mysteries that surround him a continual invitation, 

 nay, more, an inexorable mandate. Tyndall's writings abundantly prove 

 that he had faced the great problems of man's existence with that calm 

 intellectual courage, the lack of which goes very far to explain the nervous 

 dogmatism of nescience. Just because he had done this, because he had, 

 as it were, mapped out the boundaries between what is knowable though 

 not yet known and what must remain for ever unknowable to man, he 

 did not hesitate to place implicit reliance on the progress of which man is 

 capable, through the exercise of patient and persistent research. In 

 Tyndall's scheme of thought the chief dicta were the strict division of the 

 world of knowledge from that of emotion, and the lifting of life by 

 throwing overboard the malign residuum of dogmatism, fanaticism, and 

 intolerance, thereby stimulating and nourishing a plastic vigour of intellect. 

 His cry was ' Commotion before stagnation, the leap of the torrent before 

 the stillness of the swamp.' 



His successors have no longer any need to repeat those significant 

 words, ' We claim and we shall wrest from theology the entire domain of 

 cosmological theory.' The claim has been practically, though often 

 unconsciously, conceded. Tyndall's dictum, ' Every system must be plastic 

 to the extent that the growth of knowledge demands,' struck a note that 

 was too often absent from the heated discussions of days that now seem so 

 .strangely remote. His honourable admission that, after all that had been 

 achieved by the developmental theory, 'the whole process of evolution is 

 the manifestation of a power absolutely inscrutable to the intellect of 

 man,' shows how willingly he acknowledged the necessary limits of 

 scientific inquiry. This reservation did not prevent him from expressing 

 the conviction forced upon him by the pressure of intellectual necessity, 

 after exhaustive consideration of the known relations of living things, 

 that matter in itself must be regarded as containing the promise and 



