ttempting to trace the source of a personality,
hereditarily, no constancy could be detected in its relation to the
lives from which it arose. A child was never absolutely like brother,
sister, mother, father or grandparent.

An epoch-making discovery in 1865 by an Austrian monk named Mendel,[57]
and later discoveries by a number of other scientists, revealed the
subdivisibility of each individual into many distinct units or traits,
the hereditary sources of which were clearly traceable, leading to
various individuals of the family line, and not to one individual alone.
Furthermore, it was found that the lack of a certain trait sometimes
appears as a trait in itself, just as darkness seems like a condition in
itself rather than as an absence of light.

These discoveries changed the whole current of thought regarding
heredity, and the constancy of its action, as well as its
controllability. It also emphasized the fact that it does make a
difference whom one marries as to the character of the resulting
offspring. Their makeup is not subject to the caprice of forces beyond
human perception, but is in some degree subject to control.

Out of these discoveries has arisen the science of Eugenics. Sir Francis
Galton, of England, was the first to start a world movement for its
application toward conscious betterment of the human stock.

[Sidenote: Rules of Eugenics]

From the known laws governing the inheritability of unit-traits, it is
apparently necessary, in the betterment of the race, to follow a few
important rules:

1. Learn to analyze individuals into their inheritable traits--physical,
mental and moral.

2. Differentiate between socially noble and ignoble traits, between
social and educational veneer and sterling inherent capacity.

3. Do not expect physical, mental and moral perfection in any one
individual, but look for a majority of sterling traits.

4. Observe the presence or absence of specific traits in individuals at
all ages of successive generations and fraternities of a family line.

5. Learn how to estimate the inheritability of such traits in a family
line, upon specific mating with another family line.

6. Join your family line to one which is strong in respect to the traits
in which yours is weak.

7. But remember also that injuries can be inflicted on offspring by
unhygienic living.

[Sidenote: Inheritable Traits]

Some of the characteristics in Man's complex known to act hereditarily
and