PROFESSOR VIRCHOW AND EVOLUTION. 401 



utter absence of any proof of the illegality of the act, 

 they prolong the method of nature from the present 

 into the past. Here the observed uniformity of nature 

 is their only guide. Having determined the elements 

 of their curve in a world of observation and expert 

 ment, they prolong that curve into an antecedent world, 

 and accept as probable the unbroken sequence of de- 

 velopment from the nebula to the present time.' Thus 

 it appears that, long antecedent to the publication of 

 his advice, I did exactly what Professor Virchow recom- 

 mends, showing myself as careful as he could be not 

 to claim for a scientific doctrine a certainty which did 

 not belong to it. 



I now pass on to the Belfast Address, and will cite 

 at once from it the passage which has given rise to the 

 most violent animadversion. ' Believing as I do in the 

 continuity of nature, I cannot stop abruptly where our 

 microscopes cease to be of use. At this point the vision 

 of the mind authoritatively supplements that of the 

 eye. By an intellectual necessity I cross the boundary 

 of the experimental evidence, and discern in that " mat- 

 ter" which we in our ignorance of its latent powers, 

 and notwithstanding our professed reverence for its 

 Creator, have hitherto covered with opprobrium, the 

 promise and potency of all terrestrial life.' Without 

 halting for a moment I go on to do the precise thing 

 which Professor Virchow declares to be necessary. ' If 

 you ask me/ I say, ' whether there exists the least evi- 

 dence to prove that any form of life can be developed 

 out of matter independently of antecedent life, my reply 

 is that evidence considered perfectly conclusive by many 

 has been adduced, and that were we to follow a com- 

 mon example, and accept testimony because it falls in 

 with our belief, we should eagerly close with the evi- 

 dence referred to. But there is in the true man of 



