k alcoholic beverages, will
have defective offspring.

(3) It may be that the degeneracy observed in the children of drunkards
(for of course no one will deny that children of drunkards are
frequently defective) is due solely to social and economic causes, or
other causes in the environment: that the drunken parents, for instance,
do not take adequate care of their children, and that this lack of care
leads to the defects of the children.

The latter influence is doubtless one that is nearly always at work, but
it is wholly outside the scope of the present inquiry, and we shall
therefore ignore it, save as it may appear incidentally. Nor does it
require emphasis here; for the disastrous social and economic effects of
alcoholism are patent to every observer. We find it most convenient to
concentrate our attention first on the second of the questions above
enumerated: to ask whether there is any good evidence that the use of
alcoholic beverages by men and women really does originate degeneracy in
their offspring.

To get such evidence, one must seek an instance that will be crucial,
one that will leave no room for other interpretations. One must,
therefore, exclude consideration of cases where a mother drank before
child birth. It is well-known that alcohol can pass through the
placenta, and that if a prospective mother drinks, the percentage of
alcohol in the circulation of the unborn child will very soon be nearly
equal to that in her own circulation. It is well established that such a
condition is extremely injurious to the child; but it has nothing
directly to do with heredity. Therefore we can not accept evidence of
the supposed effect of alcohol on the fertilized egg-cell, at any stage
in its development, because that is an effect on the individual, not on
posterity. And the only means by which we can wholly avoid this fallacy
is to give up altogether an attempt to prove our case by citing
instances in which the mother was alcoholic. If this is not done, there
will always be liability of mistaking an effect of prenatal nutrition
for a direct injury to the germ-plasm.

But if we can find cases where the mother was of perfectly sound stock,
and non-alcoholic; where the father was of sound stock, but alcoholic;
and where the offspring were impaired in ways that can be plausibly
attributed to an earlier injury to the germ-plasm by the father's
alcohol; then we have evidence that must weigh heavily with the
fair-min