belong to strains containing the same
defect, have some (about 25 per cent) defective children. But a
defective married to a pure normal will have no defective offspring.

The clear eugenical rule is then this: Let abnormals marry normals
without trace of the defect, and let their normal offspring marry in
turn into strong strains; thus the defect may never appear again.
Normals from the defective strain may marry normals of normal ancestry,
but must particularly avoid consanguineous marriages.

The sociological conclusion is: Prevent the feeble-minded, drunkards,
paupers, sex-offenders, and criminalistic from marrying their like or
cousins or any person belonging to a neuropathic strain. Practically it
might be well to segregate such persons during the reproductive period
for one generation. Then the crop of defectives will be reduced to
practically nothing.

3. Inheritance of Acquired Nature: Tradition[77]

The factor in societal evolution corresponding to heredity in organic
evolution is tradition; and the agency of transmission is the nervous
system by way of its various "senses" rather than the germ-plasm. The
organs of transmission are the eye, ear, tongue, etc., and not those of
sex. The term tradition, like variation and selection, is taken in the
broad sense. Variation in nature causes the offspring to differ from the
parents and from one another; variation in the folkways causes those of
one period (or place) to differ from their predecessors and to some
extent among themselves. It is the vital fact at the bottom of change.
Heredity in nature causes the offspring to resemble or repeat the
present type; tradition in societal evolution causes the mores of one
period to repeat those of the preceding period. Each is a stringent
conservator. Variation means diversity; heredity and tradition mean the
preservation of type. If there were no force of heredity or tradition,
there could be no system or classification of natural or of societal
forms; the creation hypothesis would be the only tenable one, for there
could be no basis for a theory of descent. If there were no variation,
all of nature and all human institutions would show a monotony as of the
desert sand. Heredity and tradition allow respectively of the
accumulation of organic or societal variations through repeated
selection, extending over generations, in this or that direction. In
short, what one can say of the general effects of heredity in the
orga