1875.] Heredity. 161 
designates as ‘‘ heredity of influence,” a form rare indeed, but 
still thoroughly established. Any female animal may pro- 
duce offspring resembling not her present, but a former 
mate, who may have been dead for years. However in- 
teresting this phenomenon may beas a physiological problem, 
it is too rare among the human species to have any impor- 
tant bearing upon our subject.* 
But when the action—often conflicting—of all these forms 
of heredity has been duly taken into account, there is still a 
residuum, to which M. Ribot gives the name of ‘‘ sponta- 
neity.” Occasionally, though not often, a man appears, 
eminent for good or for evil, whose genealogy throws no 
light at all upon his peculiar attributes, or seems even in 
flat contradiction to what the law of heredity would at first 
sight lead us to expect. But we must remember, that in 
many instances nothing is known of the ancestry or of the 
collateral relatives of a man of genius. Before he rose to 
celebrity these points excited no curiosity; when his repu- 
tation is established, the inquiry comes too late. It is very 
true, as M. Ribot remarks, that ‘“‘ merit does not belong 
exclusively to history.” If we look upon the intellect, not asa 
single force, but as a complex of faculties, we shall find little 
to perplex us in the phenomenon of spontaneity. Suppose 
a family who have possessed some of the attributes of great- 
ness, but who, in virtue of a principle equally true in psy- 
chology and in mechanics, that ‘‘nothing is stronger than 
its weakest part,’’ has remained in obscurity. Let a man 
of this family marry a woman whose faculties are the com- 
plement of his own. It is possible that a child of sucha 
couple may combine the defects or the weaknesses of both 
parents, and we have then the case of spontaneous imbe- 
cility, or criminality. But it is also possible that he may 
combine the excellences of both, and burst upon the world 
as a spontaneous genius. As to the laws which deter- 
mine whether of these two cases shall be realised, we 
are still utterly in the dark. Perhaps the state of the 
parents at the moment of procreation is the clue to the diffi- 
culty. 
Again we must remember, that even if we consider the 
intellect as ‘‘ one and indivisible,” it is far from being the 
only faculty needful for the attainment of excellence, even 
in the fields of pure science. Combined with it there must 
* There is a form of heredity still more obscure, and requiring further inves- 
tigation. Ifa female animal, pregnant by one male, has during pregnancy 
frequent connection with another male, the offspring may, to some extent, 
resemble the latter. 
