erhaps under the influence of the materialism current in his youth, he
clothed his essentially vitalistic thought? Everything goes to prove
it--his constant preoccupation with psychological questions, his tacit
assimilation of organ-formation to instinctive behaviour, his constant
insistence on the importance of _besoin_ and _habitude_.

Let us not forget the profundity of his main idea, that, exception made
for the lower forms, the animal is essentially active, that it always
_reacts_ to the external world, is never passively acted upon. Let us
not forget that he pointed out the essentially psychological moment
implied in all processes of individual adaptation. With keen insight he
realised that conscious intelligence counts for little in evolution, and
focussed attention upon the unconscious but obscurely psychical
processes of instinct and morphogenesis.

Not without reason have the later schools of evolutionary thought, who
developed the psychological and vitalistic side of his doctrine, called
themselves Neo-Lamarckians.

We shall say then that Lamarck, in spite of his materialism, was the
founder of the "psychological" theory of evolution.

Lamarck stood curiously aloof and apart from the scientific thought of
his day.[344] He took no interest in the morphological problems that
filled the minds of Cuvier and Geoffroy; he had indeed no feeling at all
for morphology. He did not realise, like Cuvier, the _convenance des
parties_, the marvellous co-ordination of parts to form a whole; he had
little conception of what is really implied in the word "organism." He
was not, like Geoffroy, imbued with a lively sense of the unity of plan
and composition, and of the significance of vestigial organs as
witnesses to that unity. He seems not to have known of the
recapitulation theory, of which he might have made such good use as
powerful evidence for evolution. Even with the German
transcendentalists, with whom in the looseness of his generalisations he
shows some affinity, he seems not to have been specially acquainted.

He was interested more in the problems suggested to him by his daily
work in the museum. He wanted to know why species graded so annoyingly
into one another; he wanted to examine critically his haunting suspicion
that species were really not distinct, and that classification was
purely conventional. The question, too, of the adaptation of species to
their environment, the problem of ecological adaptation,