_ as well as
in the inorganic world--in spite of his emphatic rejection of the theory
of Lamarck, we shall show in the next chapter. It was this conviction,
as we shall see, which led to his friendly encouragement of Darwin in
his persevering investigations and to his constant solicitude that the
results of his friend's labours should not be lost through delay in
their publication.

CHAPTER VIII

EARLY ATTEMPTS TO ESTABLISH THE DOCTRINE OF EVOLUTION FOR THE ORGANIC
WORLD

In studying the history of Evolutionary ideas, it is necessary to keep
in mind that there are two perfectly distinct lines of thought, the
origin and development of which have to be considered.

_First._ The conviction that species are not immutable, but that, by
some means or other, new forms of life are derived from pre-existing
ones.

_Secondly._ The conception of some process or processes, by which this
change of old forms into new ones may be explained.

Buffon, Kant, Goethe, and many other philosophic thinkers, have been
more or less firmly persuaded of the truth of the first of these
propositions; and even Linnaeus himself was ready to make admissions in
this direction. It was impossible for anyone who was convinced of the
truth of the doctrine of continuity or evolution in the _inorganic_
world, to avoid the speculation that the same arguments by which the
truth of that doctrine was maintained must apply also to the _organic_
world.

Hence we find that directly the _Principles of Geology_ was published,
thinkers, like Sedgwick and Whewell, at once taxed Lyell with holding
that 'the creation of new species is going on at the present day,' and
Lyell replied to the latter:--

'It was impossible, I think, for anyone to read my work and not
to perceive that my notion of uniformity in the existing causes
of change always implied that they must for ever produce an
endless variety of effects, _both in the animate and inanimate
world_[80].'

And to Sedgwick, Lyell wrote:--

'Now touching my opinion,' concerning the creation of new
species at the present day, 'I have no right to object, _as I
really entertain it_, to your controverting it; at the same time
you will see, on reading my chapter on the subject, that I have
studiously avoided laying down the doctrine dogmatically as
capable of proof. I have admitted that we have only data for
_extinction_, and I have left it to be inferred