DARWIN AND HAECKEL. 597 



as sure as I can be of any thing, that I had a thought yesterday morn- 

 ing, which I took care neither to utter, nor to write down, but my 

 conviction is an utterly unverifiable hypothesis. So that unverified, 

 and even unverifiable, hypotheses may be great aids to the progress 

 of knowledge may have a right to be believed with a high degree of 

 assurance. And, therefore, even if it be admitted that the evolution 

 hypothesis is, in great measure, beyond the reach of verification, it by 

 no means follows that it is not true, still less that it is not of the ut- 

 most value and importance. 



There is evidence which is perfectly satisfactory to competent 

 judges, that we have already learned the actual historical proeess by 

 which one existing species the horse came into existence during 

 the Tertiary epoch. The evidence, based on the analogy of known 

 developmental facts, that a three-toed Hipparion form, which lived 

 in the Miocene epoch, gave rise, by suppression of the phalanges of 

 its rudimental toes and some other slight modifications, to the appar- 

 ently one-toed later Tertiary horse, is as satisfactory to my mind as 

 the evidence, based on the analogy of known structural facts, which 

 leads me to have no doubt that the said extinct Hipparion had a sim- 

 ple stomach and a certain kind of heart. If those so-called " Baconian 

 principles," which everybody talks about and nobody dreams of put- 

 ting into practice, forbid us to draw the one conclusion, they forbid us 

 to draw the other. 



The alternative hypotheses are two : either the Deity manifested his 

 power on this earth, in the course of the Miocene epoch, by making 

 the two primitive ancestors of all the horses out of inorganic matter, 

 or something more unlike a horse than a Hipparion changed into one. 

 The latter hypothesis is gratuitous and absurd. The former is not in 

 itself absurd ; but, unless the early chapters of Genesis mean some- 

 thing contrary to what they appear to mean (and one never knows 

 what exegetic ingenuity may make of the " original Hebrew "), it is 

 shockingly heretical, and I hasten to disown it, lest, by some such se- 

 cret connection as bound Goodwin Sands w T ith Tenterden steeple, it 

 should land me in the cruelties of Caligula, and lead me to violate the 

 precepts of the sagest of physicians, by indulging in Heliogabalian 

 gluttony. 



But, if the horse really has arisen in this way, what imaginable 

 ground can there be for the enormous and, in that case, highly " un- 

 Baconian " assumption that the deer, and the ox, and the pig, have 

 arisen in any other way ? And if there is not perhaps the complete 

 evidence that we happen to possess in the case of the horse but 

 still much better evidence than there is for the authenticity and gen- 

 uineness of the books called by the name of Moses, that these ani- 

 mals have been produced by a similar method, why may not the 

 hypothesis that they have so arisen take its rank among the probable 

 conclusions of science ? Even though it must, in candor, be admitted 



