e is the subjective and therefore deeper reality. The two
cannot be ruthlessly torn apart and remain complete, nor can they be
understood, or completely interpreted, apart from each other. They are
correlative and complementary expressions for the same reality.

Similarly physical and psychical life are to be conceived as
profoundly interrelated, being respectively objective and subjective
expressions of a reality incapable of separate interpretation. Yet
each has markedly distinct characteristics and is the subject of
distinct laws of activity and development.

Heredity is of two kinds, biological heredity, transmitting innate
characters, and social heredity, transmitting acquired habits and
their physiological results.

The innate characters transmitted by biological heredity are either
physiological, anatomical, or psychical.

The acquired habits transmitted by social heredity are essentially
psychical: but they may result in acquired physiological, or even
anatomical, characters. Here belong the physiological effects of diet,
housing, clothing, occupation, education, etc., which have not yet
been taken up and incorporated into the innate physiological
constitution by biological heredity. The physiological effects of
social heredity are through the daily physical life and activity of
each individual, in accordance with the requirements of the social
order in which he is reared; and these are reached through its
influence on the acquired psychical habits, which are transmitted
through association, imitation, and the control of activities by
language and education. In biological heredity the transmission is
exclusively prior to birth, while in social heredity it is chiefly, if
not entirely, after birth.

In social heredity the transmission is not determined by
consanguinity, and therefore extends to members of alien races when
they are incorporated in the social organization.

While the transmission of biological inheritance to each offspring is
inevitable and complete, that of social inheritance is largely
voluntary. It is also more or less complete, according to the
knowledge, purpose, and effort of the individuals concerned. The
transmission of acquired social and psychic characteristics even from
parents to offspring depends on their association, and the imposition
on their offspring by parents of their own modes of life. Sharing with
parents their bodily activities, their language and their environment,
bo