an acquirement. But when are the
contents of a parent's mind transmitted to the child?

"Again, a man is capable of becoming a parent at any time between
extreme youth and extreme old age; a woman from the age of thirteen to
fourteen till nearly fifty. Between the birth of the first child and the
last such an individual changes vastly. Under stress and fear of
circumstances, under the slings and arrows of outrageous fortune, all
sorts of acquirements are made. The body becomes vigorous and then
feeble, the mind grows mature, and then senile. He or she grows
wrinkled and bowed and perhaps very wise, or perhaps much the reverse.
Yet no one viewing a baby show, a children's party, or an assembly of
adults, of whom he has no previous knowledge, can say which is the
child of the youthful and which of aged parents.

"Apparently, therefore, the whole of the parent's acquirements have no
effect on the child. _Surely no evidence could be stronger."_* [[* The
undoubted transmission of siphilis [tr. note: sic] to off-spring might
be regarded as a case of transmission of an acquired characteristic. But
the case is not in point since congenital siphilis [tr. note: sic] is,
properly, due to a prenatal infection, the bacillus entering the very
germ-plasm of the human ovum (egg). Medical science, generally, has
become very cautious in the use of the word "hereditary." There is
almost unanimity among medical men in the denial of heredity as a factor
in tuberculosis and cancer. Most physicians are honest enough to say
that they know considerably less about these things than was "known" ten
and twenty years ago.]]

Herbert Spencer claims that "the inheritance of acquired characters" is
a necessary supplement to natural selection. "Close contemplation of
the facts impresses me more strongly than ever with the two
alternatives--either there has been inheritance of acquired characters,
or there has been no evolution." Again, "the inheritance of acquired
characters, which it is now the fashion of the biological world to deny,
was by Mr. Darwin fully recognized and often insisted on." "The
neo-Darwinists, however, do not admit this cause at all." He admits that
known facts which show that acquired characters are inherited are few,
but he thinks that they are "as large a number as can be expected,
considering the difficulty of observing them and the absence of search."
From the above, we see that the biological world is against Mr.
Spencer's