ix THE DEBT OF SCIENCE TO DARWIN 453 



species that now exists or ever has existed on the globe was 

 known to involve difficulties and contradictions of the most 

 serious nature, although it was seen that many of the facts 

 revealed by comparative anatomy, by embryology, by geo- 

 graphical distribution, and by geological succession were 

 utterly unmeaning and even misleading, in view of it; yet, 

 down to the period we have named, it may be fairly stated 

 that nine-tenths of the students of nature unhesitatingly 

 accepted it as literally true, while the other tenth, though 

 hesitating as to the actual independent creation, were none 

 the less decided in rejecting utterly and scornfully the views 

 elaborated by Lamarck, by Geoffroy St. Hilaire, and at a 

 much later date by the anonymous author of the Vestiges of 

 Creation that every living thing had been produced by some 

 modification of ordinary generation from parents more or less 

 closely resembling it. Holding such views of the absolute 

 independence of each species, it almost necessarily followed 

 that the only aspect of nature of which we could hope to 

 acquire complete and satisfactory knowledge was that which 

 regarded the species itself. This we could describe in the 

 minutest detail ; we could determine its range in space and 

 in time; we could investigate its embryology from the 

 rudimental germ, or even from the primitive cell, up to the 

 perfect animal or plant ; we could learn every point in its 

 internal structure, and we might hope, by patient research 

 and experiment, to comprehend the use, function, and mode 

 of action of every tissue and fibre, and ultimately of each 

 cell and organic unit. All this was real knowledge, was solid 

 fact. But, so soon as we attempted to find out the relations 

 of distinct species to each other, we embarked on a sea of 

 speculation. We could, indeed, state how one species differed 

 from another species in every particular of which we had 

 knowledge ; but we could draw no sound inferences as to the 

 reason or cause of such differences or resemblances, except by 

 claiming to know the very object and meaning of the creator 

 in producing such diversity. And, in point of fact, the chief 

 inference that was drawn is now proved to be erroneous. It 

 was generally assumed, as almost self-evident, that the 

 ultimate cause of the differences in the forms, structures, and 

 habits of the organic productions of different countries, was 



