And now, my dear little pupil, to what conclusion do we come from all
this? To that which I announced to you from the first. Throughout the
length and breadth of creation, from the highest to the lowest grade,
every living thing is subject to the same law. Everything eats, and
eats nearly in the same manner, since everywhere the same substances
furnish the feast. I laid down in my first letter that our feeding
machine was reproduced even to the farthest limits of the animal
kingdom, though always becoming more simple as the species descends
in the scale. And afterwards, where we began the study of animals, I
told you that in this machine lay the uniformity of their construction.
Was I not right? and what could I add to all the proofs which have
developed themselves one after another, to establish the fact of this
uniformity of plan in the animal machine, in all its essential points?
And it will be to the lasting renown of the illustrious Geoffroy St.
Hilaire that it was, in the face of all the Academies and under the
fire of very learned indignation, he proclaimed this truth, which one
cannot lose sight of without losing one's way in a crowd of arbitrary
fancies.
I return, then, to the definition which I gave you in speaking of the
worm, and which is the final word of the ideas I have been endeavoring
to make you understand. _An animal is a digestive tube served by
organs._
In the first place it must eat, and for this therefore the Creator
provided first. All the rest came afterwards in order to enable it to
eat more readily, to secure its prey more easily, and to make the most
of it when eaten. The movement machine, therefore, whose history I
have promised you, is only an assistant, and not the principal feature
of the organisation, and it is not by it, therefore, that the question
can be decided, whether God has made three, four, or five animals, or
whether he has only made one.
And now, my dear little pupil, I will bid you adieu, or rather say as
the French do, "Au revoir," which means "Good-bye till we meet again,"
begging you to excuse any awkward expressions that may have escaped
me, as also my having now and then talked about things because they
have interested me, without perhaps sufficiently considering whether
they might have an equal interest for you. Yet, while the pen is still
in my hand, I will not leave you my concluding definition of an animal
without adding a word of explanation. You know nothing about such
matters yourself, but to some people my words might have the air of
a parody upon another definition, applied by those grave gentlemen the
Philosophers to man, whom they have denominated _An intelligence
served by organs_. My definition is applicable only to the animal,
and not to man, observe. Man in the natural, physical machinery of his
body, is very decidedly an animal; yet as certainly is he, by the
divine reflection which shines within him, something much more and
greater; but _what_, is so far beyond the reach of definitionthat I
shall not attempt to give you one. "Man," as Jesus Christ has
said, "lives not by bread alone, but by every word that proccedeth out
of the mouth of God." What it is that is nourished in us by that word,
is precisely what I cannot attempt to define for you; yet I think you
have understood my meaning.
Go, then, and eat your food in peace, like the pretty little animal
that you are; but do not forget to nourish also the other part of your
being; that indeed which is of the most importance, and which enables
you to ascend to your Creator.