egitimate for one science it
is legitimate for all; the fundamental axiom on which it rests, the
constancy of the order of nature, being the common foundation of all
scientific thought. Indeed, if there can be grades in legitimacy,
certain branches of science have the advantage over astronomy, in so
far as their retrospective prophecies are not only susceptible of
verification, but are sometimes strikingly verified.

Such a science exists in that application of the principles of biology
to the interpretation of the animal and vegetable remains imbedded
in the rocks which compose the surface of the globe, which is called
Palaeontology.

At no very distant time, the question whether these so-called "fossils,"
were really the remains of animals and plants was hotly disputed. Very
learned persons maintained that they were nothing of the kind, but a
sort of concretion, or crystallisation, which had taken place within the
stone in which they are found; and which simulated the forms of animal
and vegetable life, just as frost on a window-pane imitates vegetation.
At the present day, it would probably be impossible to find any sane
advocate of this opinion; and the fact is rather surprising, that
among the people from whom the circle-squarers, perpetual-motioners,
flat-earthed men and the like, are recruited, to say nothing of
table-turners and spirit-rappers, somebody has not perceived the easy
avenue to nonsensical notoriety open to any one who will take up the
good old doctrine, that fossils are all _lusus naturae._

The position would be impregnable, inasmuch as it is quite impossible
to prove the contrary. If a man choose to maintain that a fossil
oyster shell, in spite of its correspondence, down to every minutest
particular, with that of an oyster fresh taken out of the sea, was never
tenanted by a living oyster, but is a mineral concretion, there is no
demonstrating his error. All that can be done is to show him that, by a
parity of reasoning, he is bound to admit that a heap of oyster shells
outside a fishmonger's door may also be "sports of nature," and that
a mutton bone in a dust-bin may have had the like origin. And when you
cannot prove that people are wrong, but only that they are absurd, the
best course is to let them alone.

The whole fabric of palaeontology, in fact, falls to the ground unless
we admit the validity of Zadig's great principle, that like effects
imply like causes, and that the process of rea