5 8o THE POPULAR SCIENCE MONTHLY. 



in the way of the adoption of a general theory of development, which 

 the labors of many men in different fields had been preparing. The 

 ship was on the stays, prepared to glide into the ocean, when Darwin 

 came and knocked away one or two of the blocks that had been most 

 obstinately hindering her descent. The wonderful success of the 

 Darwinian theory was chiefly due to this very circumstance, that so 

 much had been already done to facilitate its acceptance. The doc- 

 trine of the correlation of force, to which Dr. Porter assigns the 

 fourth place, was, if we date it only from the publication of Grove's 

 treatise, seventeen years old when the " Origin of Species " appeared. 

 The nebular hypothesis had been waiting for over a hundred years, or 

 since the publication of Kant's " General History of Nature and The- 

 ory of the Heavens." The progress of society and perfectibility of 

 human nature were the commonplaces of the last century, which was 

 also thoroughly familiar with the discussion as to spontaneous genera- 

 tion, or the development of the organic from the inorganic. Why the 

 arguments from biology should be separated from Darwinism proper it 

 is difficult to see, considering that Darwin, from the first, based his the- 

 ory of the origin of species on biological grounds, quite as distinctly as 

 on the operation of the struggle for existence. It is Darwin, above 

 all men, who has popularized the arguments from rudimentary organs 

 and from the changing phases of embryonic life. Could Dr. Porter 

 have made good his promise to describe to us the evolution of evolu- 

 tion, if we may so express it, he would have done a very useful work ; 

 but the fact is, he has not even attempted it, but has simply given us 

 what, if we may be allowed for once to adopt a common misquota- 

 tion of Horace, may very truly be called the disjecta membra of a 

 philosophy. 



Leaving this point, however, let us inquire what the author of the 

 " Lecture on Evolution " has to say on the several heads into which 

 he has divided the subject. In regard to " Darwinism," he finds the 

 evidence for the transformation of species insufficient. He admits 

 the tendency to variation and the struggle for existence ; but does not 

 see that these, alone or principally, determine the origin of species. 

 One may go a long way with Darwin, he says, and yet fail to draw 

 the conclusion that three or four original types have been the ances- 

 tors of all other organic forms past and present. This language is du- 

 bious. It might suggest that, had Darwin been a little more liberal 

 with his archetypes, the learned doctor would have agreed with him 

 fully. What is it " to go a long way with Darwin " ? The mere 

 recognition of the tendency to variation and the struggle for existence 

 is not to go with Darwin at all : it is merely to accept his starting- 

 point, and to recognize facts that were fully recognized long before his 

 time. It is a pity that so doughty a champion of orthodoxy as Dr. 

 Porter does not tell us more distinctly what his own position is. Ap- 

 parently be rejects the theory of transformation by change of environ- 



