t that, if evolution is ever
progressive, progress is not universal? How is it that all forms do
not necessarily advance, and that simple organisms still exist? As
it happened, Darwin did not discuss this point when he first put
the _Origin_ together, and speedily came to regard this as the most
serious omission in the book.

Great, then, was the debt of all science to Darwin. And not of science
only. The fight for freedom of thought and speech in science, into
which Huxley especially threw himself, was the more successful because
the immediate cause he upheld was so overwhelmingly strong in reason
and demonstration; and, the supreme curb upon thought being once
broken, a wider freedom was gained.

For Darwin, therefore, Huxley had the reverence due to one who had
forged a new and mighty weapon in the war for plain truth. But,
while he could not but uphold a theory so much in accord with his own
knowledge and so fruitful in its promise of new knowledge, whether the
author of it were his friend or not, admiration and affection for a
man of such utter sincerity, such selfless respect for truth, and warm
personality, led him, when those views were stupidly or maliciously
attacked, to take more trouble in his defence and support, and to
strike out much harder at his adversary than he would otherwise have
done. Darwin's friends were well assured that the scanty time which
his health allowed for work was far too precious to be wasted in
controversy; for his own sake and for the sake of the calm atmosphere
in which a great theory should be worked out, they thought that the
battling on a lower plane should be left to them. "You ought to be
like one of the blessed gods of Elysium, and let the inferior deities
do battle with the infernal powers." "If I say a savage thing," Huxley
told him, "it is only 'pretty Fanny's way'; but if you do, it is not
likely to be forgotten." Hence a dash of personal pleasure was infused
into the duty of upholding and defending the bringer of new light.

The acquaintance had begun about 1851; there was a common bond in
their sea experiences and explorations, as well as in their search
after a wider philosophy, to include the teachings of natural science;
the older man found in the younger a source of much biological and
other information, a suggestive critic and a stimulating companion.
Their relations took a long step towards intimacy after 1861, when,
after the loss of her eldest child, Mrs. Hux