Permanence and Evolution. 93 



merely on conjectures and legends. I feel con- 

 vinced myself that if such spontaneous variation 

 does exist, it will be shown to be of the most 

 limited and trifling kind ; but what is the truth 

 as to this, time and experiment I hope will show. 

 If, however, we go further arid ask the origin 

 of the primitive and immutable forms of organ- 

 ised life, all we can say is, that we know of no 

 cause adequate to produce them, either out of 

 each other, or out of inorganic matter. We 

 may guess, if we like, and no one has a right to 

 complain of another for guessing, so long as he 

 knows and admits that his guess is neither a 

 scientific discovery nor a scientific hypothesis. 

 If we are to guess at all, I quite agree that some 

 form of evolution is one of the most plausible 

 guesses we can at present make ; but I think 

 the analogies on which it rests, though often 

 tempting, may very likely be entirely misinter- 

 preted ; and it seems to me, personally, that the 

 best thing we can do is to abstain from conjee- 



