THE DARWINIAN HYPOTHESIS 129 



a reason for many apparent anomalies in the distribution 

 of living beings in time and space, and that it is not con- 

 tradicted by the main phenomena of life and organization 

 appear to us to be unquestionable, and so far it must be 

 admitted to have an immense advantage over any of its 

 predecessors. But it is quite another matter to affirm 

 absolutely either the truth or falsehood of Mr. Darwin's 

 views at the present stage of the inquiry. Goethe has an 

 excellent aphorism defining that state of mind which he 

 calls Thdtige Skepsis active doubt. It is doubt which 

 so loves truth that it neither dares rest in doubting, nor 

 extinguish itself by unjustified belief ; and we commend 

 this state of mind to students of species, with respect to 

 Mr. Darwin's or any other hypothesis, as to their origin. 

 The combined investigations of another 20 years may, 

 perhaps, enable naturalists to say whether the modifying 

 causes and the selective power, which Mr. Darwin has 

 satisfactorily shown to exist in nature, are competent to 

 produce all the effects he ascribes to them, or whether, on 

 the other hand, he has been led to over-estimate the value 

 of his principle of natural selection, as greatly as Lamarck 

 over-estimated his vera causa of modification by exercise. 

 But there is, at all events, one advantage possessed by 

 the more recent writer over his predecessor. Mr. Darwin 

 abhors mere speculation as nature abhors a vacuum. He 

 is as greedy of cases and precedents as any constitutional 

 lawyer, and all the principles he lays down are capable of 

 being brought to the test of observation and experiment. 

 The path he bids us follow professes to be not a mere 

 airy track, fabricated of ideal cobwebs, but a solid and 

 broad bridge of facts. If it be so, it will carry us safely 

 over many a chasm in our knowledge, and lead us to a 

 region free from the snares of those fascinating but barren 

 Virgins, the Final Causes, against whom a high authority 

 has so justly warned us. " My sons, dig in the vineyard," 

 were the last words of the old man in the fable ; and, 

 though the sons found no treasure, they made their for- 

 tunes by the grapes. 



66 B 



