though I fully admit that it is the highest and most interesting
problem for the naturalist." But his conscientiousness compelled him
to state briefly his opinion on the subject in the _Origin of Species_
in 1859. Nevertheless he did not escape reproaches for having been so
reticent. This is unmistakably apparent from a letter to Fritz Mueller
dated Feb. 22 [1869?], in which he says: "I am thinking of writing a
little essay on the Origin of Mankind, as I have been taunted with
concealing my opinions."[83]

It might be thought that Darwin behaved thus hesitatingly, and was so
slow in deciding on the full publication of his collected material in
regard to the descent of man, because he had religious difficulties to
overcome.

But this was not the case, as we can see from his admirable confession
of faith, the publication of which we owe to his son Francis.[84]
Whoever wishes really to understand the lofty character of this great
man should read these immortal lines in which he unfolds to us in
simple and straightforward words the development of his conception of
the universe. He describes how, though he was still quite orthodox
during his voyage round the world on board the _Beagle_, he came
gradually to see, shortly afterwards (1836-1839) that the Old
Testament was no more to be trusted than the Sacred Books of the
Hindoos; the miracles by which Christianity is supported, the
discrepancies between the accounts in the different Gospels, gradually
led him to disbelieve in Christianity as a divine revelation. "Thus,"
he writes,[85] "disbelief crept over me at a very slow rate, but was
at last complete. The rate was so slow that I felt no distress." But
Darwin was too modest to presume to go beyond the limits laid down by
science. He wanted nothing more than to be able to go, freely and
unhampered by belief in authority or in the Bible, as far as human
knowledge could lead him. We learn this from the concluding words of
his chapter on religion "The mystery of the beginning of all things is
insoluble by us; and I for one must be content to remain an
Agnostic."[86]

Darwin was always very unwilling to give publicity to his views in
regard to religion. In a letter to Asa Gray on May 22, 1860,[87] he
declares that it is always painful to him to have to enter into
discussion of religious problems. He had, he said, no intention of
writing atheistically.

Finally, let us cite one characteristic sentence from a letter from
Dar