It has been well said by Herbert Spencer, and more recently by Professor
Osborn, the able biologist of Columbia College, that the question
involved in the discussion of heredity is not a temporary issue and that
its solution will affect all future thought. Whether or not acquired
character is transmitted to children is the most important question that
confronts the human race; for it is upon the character of the race that
depends and will depend the condition of the race.
No school of scientists questions the fact of heredity; but there is
a warm and greatly misunderstood contest over the exact method used
by nature in the transmission. Now so far as the general public is
concerned, so far as the sociological features of the case go, so far
as personal conduct is involved, it does not matter a straw's weight
whether the theory of heredity held by Lamarck and Darwin, or the one
advanced recently by Weismann, be correct.
It matters not whether your drunkenness, for example, is transmitted to
your child directly as plain drunkenness, or whether it descends to him
as a merely weakened and undermined "germ plasm" which "will tend
to inebriety, insanity, imbecility" or what not. It matters not a
farthing's worth, from the point of view of the laity, whether the
transmission is direct, via "pangenesis," or whether it is indirect,
via a weakened and vitiated "germ plasm" as per Weismann, or whether the
exact method and process may not still lie in the unsolved problems of
the laboratory. Whichever or whatever the exact process may be (which
interests the scientist only), the facts and results are before us and
concern each of us more vitally than does the question of what we shall
eat or what we shall drink or wherewithal we shall be clothed. It is all
the more unfortunate, therefore, that even an untested scientific theory
cannot be advanced without the ignorant, the half-educated and the
vicious taking it in some distorted form as a basis of action. Indeed it
would seem to be wise, if one is about to make a scientific suggestion
of importance, to take the precaution to say in advance that you
don't mean it--for the benefit of that large class of intellectual
batrachians who hop to the conclusion that you said something totally
different from your intent.
Because a surgeon might say to you that he knows a boy who carries a
bullet about in his brain and that the youth appears to be no worse
for it in either body or mind, it would not be safe to imply that he
proposes to teach you that it would be a particularly judicious thing
for you to attempt to convert your skull into a cartridge box.
Because Weismann asserts and attempts to prove that nature's method
of hereditary transmission precludes (for example) the possibility
of producing a race of short-tailed cats from Tom and Tabby from whose
caudal appendages a few inches have been artificially subtracted, some
of his followers exclaim in glee: "It does not make the least difference
in the world what we do or refrain from doing in one lifetime. Our
children do not receive the results; we cannot transmit to them our
vices or our virtues. We cannot taint their blood by our ill conduct nor
purify it by our clean living. The 'germ plasm' from which they came
is and has been immortal; we are simply its transmitters--not its
creators. Our children were created and their characters and natures
determined centuries before we were bom. We are in no sense responsible
for what they may be; germ plasm is eternal; we are exempt from
responsibility to posterity. Long live Weismann!"
Now this is about the sort of thing that is springing up on every side
as a result of the new discussion as to how we are to account for the
facts of heredity. One sometimes hears, also, from these half-informed
jubilators that "Weismann does not believe in heredity; that old theory
is quite exploded." The fact is that Weismann is particularly strong
in his belief in heredity--so strong as to give almost no weight to any
possible process of intervention in its original workings. He simply
holds that the transmission of "acquired character" is not proven,
and he doubts the fact of these "acquired" transmissions. In his
illustrations he deals chiefly (when in the higher animals) with
mutilations, and in the human race shows that the most proficient
linguist does not produce children who can read without being taught!
Of course there are many and varied points in his theory of heredity
with which only the biologist is capable of dealing. But as I intimated
at first, the Lamarck-Darwin-Weismann controversy, so far as the
sociological aspect of the question is involved, does not touch us.
It belongs to the laboratory--to the how and not to the fact of
transmission. But since the opposite impression has taken root in even
some thoughtful minds, it is well to meet it in a direct and easily
grasped form. There is a simple and direct method; I undertook it. I
went to a number of well-known biologists and physicians and asked these
questions;--
1. Are there any diseases known to you, which you are absolutely certain
are contracted by individuals whose ancestors did not have them, which
diseases you can trace as to time and place of contraction, and
which are of a nature to produce physical and mental changes that are
recognizable in the child as due to the parent's condition?