BRITISH ASSOCIATION : ZOOLOGICAL SECTION. 357 



day the grand tree of each great phylum, maybe of the whole king- 

 dom, might be reconstructed. That would indeed be a tree of know- 

 ledge, and, paradoxically enough, it would be the deathblow to 

 classification, since in this, the one and only true natural system, 

 every degree of consanguinity and relationship throughout all ani- 

 mated nature, past and present, would be accounted for ; and to that 

 system no classification would be applicable, since each horizon 

 would require its own grouping. There could be definable neither 

 classes, orders, families, nor species, since each of these conceptions 

 would be boundless in an upward or downward direction. 



Never mind the ensuing chaos ; we should at least have the pedi- 

 gree of all our fellow creatures, and of ourselves among them. Not 

 absolute proof, but the nearest possible demonstration that trans- 

 formation has taken place. Empirically we know this already, since, 

 wherever sufficient material has been studied, be it organs, species, 

 or larger groups, we find first that these units had ancestors, and, 

 secondly, that the ancestors were a little different. Evolution is a 

 fact of experience proved by circumstantial evidence. Nevertheless, 

 we are not satisfied with the conviction that life is subject to an 

 unceasing change, not even with the knowledge of the particular 

 adjustments. We now want to understand the motive change. First 

 What, then How, and now Why? 



It is the active search for an answer to this question (Why ?) 

 which is characteristic of our time. More and more the organisms 

 and their organs are considered as living, functional things. The 

 mainspring of our science, perhaps of all science, is not its utility, not 

 the desire to do good, but, as an eminently matter-of-fact man, the 

 father of Frederick the Great, told his Royal Academicians (who, of 

 course, were asking for monetary help) in the following shockingly 

 homely words: " Der Grund ist derer Leute ihre verfluchte Curieu- 

 siteit." This blamed curiosity, the beginnings of which can be traced 

 very far back in the lower animals, is most acutely centred in our 

 desire to find out who we are, whence we have come, and whither 

 we shall go. And even if Zoology, considering the first and last of 

 these three questions as settled, should some day solve the problem : 

 Whence have we come ? there would remain outside Zoology the 

 greater Why ? 



Generalizations, conclusions, can be arrived at only through com- 

 parison. Comparison leads no further where the objects are alike. 

 If, for instance, we restrict ourselves to the search for true homo- 

 logies, dealing with homogenes only, all we find is that once upon a 

 time some organism has produced, invented, a certain arrangement 

 of Anlage out of which that organ arose, the various features of which 

 we have compared in the descendants. Result : we have arrived at 

 an accomplished fact. These things, in spite of all their variety in 

 structure and function, being homogenes, tell us nothing, because 

 according to our mode of procedure we cannot compare that mono- 

 phyletic Anlage with anything else, since we have reduced all the 

 homogenous modifications to one. Logically, it is true that there 

 can have been only one, but in the living world of nature there are 



