234 L. Manouvrier — Pithecanthropus erectus. 



2d. During the Pliocene epoch, there lived in Java an 

 anthropoid race possessing the " marche bipede," and inter- 

 mediate, in cerebral development, "between the highest forms 

 of known monkeys and the human species. 



We may fuse these two hypotheses into one, from the point 

 of view of the theory of evolution, that is to say, we may con- 

 sider with great probability the race in question not only as a 

 race precursor for the human species, but also as a race ances- 

 tral, as the commencement of humanity. 



That there is in all this much hypothesis, I do not deny. But 

 the attributing of the pieces from Trinil to two or three 

 unknown species closely resembling man, or to a single abnor- 

 mal specimen of the human species, that is, also, merely hypoth- 

 esis. 



Then, since we are obliged to have recourse, in any case, to 

 a hypothesis, we have to ask which one is the most suitable, 

 not only to explain the facts directly on trial, but also to clear 

 up this question henceforth thrust imperiously before us for 

 examination, namely, what can have been the human species 

 during the Pliocene and how can it have originated ? In the 

 presence of the discovery of Mr. Dubois, it is advisable to 

 examine the question in its entirety. 



The question does not admit of a mathematical demonstra- 

 tion, but there can be a degree of probability great enough to 

 carry with it conviction. To admit as true, until there is proof 

 to the contrary, a hypothesis which answers to a great number 

 of facts without being contradicted by any, is to act in accord- 

 ance with the scientific spirit. It has often been said that 

 science does not consist in a heap, but in a chain, of facts. To 

 discover this chain, hypothesis plays a necessary role. Certain 

 zoologists suppose that the human species has had no ancestors. 

 If this hypothesis, of which the probability is not of the first 

 order, seems to them to be scientific and fruitful, the opposite 

 hypothesis can boast of titles to belief at least equal, in our 

 opinion. And if the human species did not appear by spon- 

 taneous generation, — if, on the other hand, the cranial characters 

 of Quaternary man found in Europe represented a phase of 

 evolution very little removed from the existing phase, there is 

 cause for believing that there would be found in Pliocene deposits 

 a race morphologically inferior to that of Neanderthal and of 

 Spy. But this is precisely what has happened. The anthro- 

 pomorphous human race, if you choose to call it so, found by 

 Mr. Dubois, presents characters such that it may have resulted 

 directly and progressively from the transformation of a race of 

 anthropoid climbers. Under these conditions, if the doubt 

 on the subject of the simian origin of Man is only proportion- 

 ate to the reasons of a scientific order capable of giving rise to 

 it, it seems to me it must be a very slender doubt. 



