plied in this movement itself, and that is just why it is
found in independent lines of evolution. If now we are asked why and how
it is implied therein, we reply that life is, more than anything else, a
tendency to act on inert matter. The direction of this action is not
predetermined; hence the unforeseeable variety of forms which life, in
evolving, sows along its path. But this action always presents, to some
extent, the character of contingency; it implies at least a rudiment of
choice. Now a choice involves the anticipatory idea of several possible
actions. Possibilities of action must therefore be marked out for the
living being before the action itself. Visual perception is nothing
else:[50] the visible outlines of bodies are the design of our eventual
action on them. Vision will be found, therefore, in different degrees in
the most diverse animals, and it will appear in the same complexity of
structure wherever it has reached the same degree of intensity.

We have dwelt on these resemblances of structure in general, and on the
example of the eye in particular, because we had to define our attitude
toward mechanism on the one hand and finalism on the other. It remains
for us to describe it more precisely in itself. This we shall now do by
showing the divergent results of evolution not as presenting analogies,
but as themselves mutually complementary.

FOOTNOTES:

[Footnote 3: _Matiere et memoire_, Paris, 1896, chaps. ii. and iii.]

[Footnote 4: Calkins, _Studies on the Life History of Protozoa (Archiv
f. Entwicklungsmechanik_, vol. xv., 1903, pp. 139-186).]

[Footnote 5: Sedgwick Minot, _On Certain Phenomena of Growing Old_
(_Proc. Amer. Assoc. for the Advancement of Science_, 39th Meeting,
Salem, 1891, pp. 271-288).]

[Footnote 6: Le Dantec, _L'Individualite et l'erreur individualiste_,
Paris, 1905, pp. 84 ff.]

[Footnote 7: Metchnikoff, _La Degenerescence senile_ (_Annee
biologique_, iii., 1897, pp. 249 ff.). Cf. by the same author, _La
Nature humaine_, Paris, 1903, pp. 312 ff.]

[Footnote 8: Roule, _L'Embryologie generale_, Paris, 1893, p. 319.]

[Footnote 9: The irreversibility of the series of living beings has been
well set forth by Baldwin (_Development and Evolution_, New York, 1902;
in particular p. 327).]

[Footnote 10: We have dwelt on this point and tried to make it clear in
the _Essai sur les donnees immediates de la conscience_, pp. 140-151.]

[Footnote 11: In his fine work on _Genius in