330 The Mnemonic Phenomenon 
the persistence of conditions latent in memory. Let us 
note further, that these last two cases present in a very 
striking form one of those “revivifications of memory 
through contiguity in space,” as Ribot would call them. 
This reawakening of memory through contiguity in 
space is only a particular case of the general law of the 
association or succession of ideas. They indicate that 
the mnemonic center becomes active only when the sight 
of the same place induces in the environment of that 
center almost the same state of distribution of nervous 
energy as was present at the former time when it received 
the impression. That is exactly, as we have seen in 
the preceding chapter, the immediate result of the hypoth- 
esis of specific elementary accumulators there advanced. 
In the mnemonic phenomena properly so called, it 
is the infinitely diverse and constantly changing condi- 
tions of the outer world and the corresponding sensa- 
tions following in the individual which call forth like 
a phantasy such and such an association or succession 
of ideas. But in the development of the embryo which 
is removed from the action of every external perturbing 
influence and above all, which is provoked by the acti- 
vation of different specific germinal elements from one 
and the same complex mnemonic center constituted by 
the germinal substance, the succession of mnemonic states 
of this latter called into activity one after the other and 
of the corresponding stages of ontogeny must inevitably 
proceed in an uninterrupted series, always the same for 
all individual ontogenies of the same species. For to 
reawaken each mnemonic element of this germinal sub- 
stance there must again concur exactly and exclusively 
those conditions of distribution of nervous energy in 
