148 THE SURVIVAL OP THE UNLIKE. [v. 



which he accomplished, seem to place Van Mons in the 

 very front rank of those bolder men who, by the aid of 

 science and philosophy, have contribnted to the perma- 

 nent advan(?ement of the cnltivation of plants. Yet one 

 will find that this fame rests more npon a regard for the 

 man and the varieties which he produced, than upon an 

 acceptance of his system. Van Mons was unfortunate 

 in having a theory to prove by means of experiment, 

 rather than in attempting to construct a theory as the 

 result of experiment. He assumed, as most persons do 

 at the present day, that there is some mysterious or 

 hidden means which, if discovered, will enable the 

 operator to produce forthwith and with certainty such 

 plants as he desires. This appears to have been the 

 almost universal type of mind in pre -Darwinian times. 

 Even Loiseleur-Deslongchamps, whilst refusing to ac- 

 cept Van Mons' system, yet writes in 1842 that "we 

 are still ignorant of a positive means by which we can 

 proceed with certainty to produce new fruits of the best 

 quality ; it is a mystery of which nature guards the 

 secret." We are now convinced that this attitude of 

 mind is erroneous, and that it is rarely productive of 

 useful results in investigation. 



One might think, from the bare statement of his 

 principles, that Van Mons had really anticipated some of 

 the characteristic generalizations of Darwin. One of the 

 most important and inextricable problems now before 

 philosophical naturalists is the source or cause of vari- 

 ations or differences between individuals of any species. 

 There are some thinkers who refer all useful or perma- 

 nent tendencies towards variation to innate or predis- . 

 posed inclinations; and there are others, like the La- 

 marckians and Darwinians, who believe that much, or 



