considered from some special poi tits of view. 419 



cited in opposition to it than definite assertions are contained 

 in it. The indefiniteness of the theory causes an equally 

 great indefiniteness in its refutation, Tlie above arguments 

 against the Darwinian opinion, derived from the results of 

 paleontology, make no claim to be unassailable. But so far 

 as it can be regarded as possible to demonstrate the produc- 

 tion of an injurious property from the multifarious data stand- 

 ing at the command of Darwinism, even in connexion with 

 this point, it must be the case here. The abridgment of the 

 duration of life is such a property. 



The species of the animal kingdom have been very aptly 

 compared with the paths of the planets (Blasius, ' Fauna 

 Deutschlands,' preface). The orbits of the planets are not 

 invariable, any more than a given species of animals is exactly 

 the same in one year as in another. The variations, however, 

 are, for long periods, confined within definite limits. But, 

 strictly speaking, this cannot be proved for cdl time^ as in this 

 case Ave must also take into consideration the matter existing 

 between the planets &c. Nor can we conclude from the pre- 

 sent state of the planetary system as to any given earlier period. 

 It has been attemjDted to derive the present state of the pla- 

 netary system from an earlier simpler one — as which a rotating 

 nebular sphere was assumed. This hypothesis was first pro- 

 posed by Kant, who, however, was by no means the profound 

 mathematician that he is represented by Hackel (Natiirliche 

 Schopfungsgeschichte) . Laplace subsequently presented it in 

 a somewhat more mathematical dress, though not in his strictly 

 scientific ' Mecanique Celeste,' but in a more popular work. 

 Among astronomers, however, it is in tolerable estimation, 

 but only as a simple h}q)othesis, which is quite incapable of 

 further development into an actual theory (as has been shown 

 by the attempt made by Weiss). 



The Darwinian doctrine also will perhaps always number 

 its adl\erents, as, indeed, its erroneous natm'e can no more be 

 strictly demonstrated than that of any view as to the flora and 

 fauna of the moon. But every attempt to convert the hypothesis 

 definitely into a theory, even if it should be in tolerable agree- 

 ment with zoological, botanical, and palffiontological facts, 

 would always have something arbitrary about it, as a thou- 

 sand others might be set in its place. 



Considering the near affinity of Laplace's hypothesis of 

 creation and the Darwinian doctrine, it was to be expected 

 that the Darwinists would revert to the former. All such 

 physical views originate from a weakness which attaches even 

 to the greatest naturalists — namely, the tendency to deduce 

 everywhere multiplicity from unity. This has its foundation 



