50 NATURE AND LIFE. 
fact, that which gives their character to these primordial 
elements of life is dynamic actuality. Let us consider a 
dead cell and a living cell. What makes the difference be- 
tween them? Nothing at all, either from the geometrical 
point of view, or from the physical or chemical one; noth- 
ing which may be detected by measurement, or balances, 
orreagents. The difference between them is, that the for- 
mer is devoid of the activity which exists in the latter. 
That activity is a continuous inmost transmutation, by 
which the matter of the cell is incessantly renewed, with- 
out any modification of its morphological appearances or 
of its other properties. Life consists in this tide which 
flows deep through every element in the organization, in 
that virtue of instability which effects unceasing change 
in the matter of appearances, while the form and the force 
do not vary. It exists in those organic properties, pure 
forces, which are constant, while the organs, the visible 
forms, are passing. Therefore, in opposition to the belief 
of materialism, and in accordance with Leibnitz’s views, 
matter, in such case, is merely the shifting envelope; the 
unchangeable base isforce. In addition to nutrition, which 
has just been defined, other manifestations of life are, 
through organization, development, contractility, feeling, 
thought, will. These other aspects yield us the same dem- 
onstration. The utter impossibility of producing any 
thing organized with mere inorganic forces, the impotence 
of spontaneous generation in the first place, testifies that 
organization possesses a higher principle than that of the 
phenomena of the mineral kingdom: but organization is 
not the only thing that it is forbidden to attribute to the 
working of physico-chemical means; the same holds true 
of contractility, sensibility, and a fortiori of thought and 
will. The greater the development of experimental science, 
the more decided is the difference between these two or- 
ders of phenomena, which theory held might be con- 

