r which acts, and
the manner in which it acts. If the naturalist thinks that his science
is everything, he must conclude that we can know nothing beyond the
laws, and that an insuperable ignorance hides from our view the power of
which they express the action. But he rarely succeeds in keeping this
position, and deceives his reason by confounding the laws which he
discovers with the causes with which his mind is not able to dispense.
He says first of all with Franchi, "the universe is what it is"; this is
the general formula of all the truths of experience; then he adds with
the same author, "it is because it is." This _because_ means nothing, or
means that laws are their own causes. If it is asked, What is the cause
of the motion of the stars? they will give for answer the astronomical
formulae which express this motion, and will think that they have
explained the phenomena by stating in what way they present themselves
to observation. This is a curious example of that confusion of ideas
which opens the door to atheism.

An English naturalist, Mr. Darwin, has shown that in the successive life
of animal generations, the favorable variations which are produced in
the organization of a being are transmitted to its descendants and
insure the perpetuity of its race, while the unpropitious variations
disappear because they entail the destruction of the races in which they
are produced. He tells us: "This preservation of favorable variations
and the rejection of injurious variations, I call Natural
Selection."[114] What does the author understand by law? He answers:
"the series of facts as it is known to us."[115] Here we have the true
definition of law: it is the simple expression of the series of the
facts; the cause remains to be sought for. I open the book in another
part. The author is speaking of the eye; and his doctrine is that the
eye of the eagle was formed by the slow transformations of an extremely
simple visual apparatus. There will have been then, in the development
of animal existence, first of all a rudimentary eye, then an eye
moderately well formed, and then the eye of the eagle, because the
favorable modifications of the organ of sight will have been preserved
and increased in the course of ages. Such is the series of facts, such
is the law; suppose we grant it. What is the cause? The optician makes
our spectacles; who made the eye of the eagle, by directing the slow
transformations which at length produced