raordinary way in large homogeneous gatherings. The contrast
between a mass meeting of one race and a similar meeting of another is
particularly striking. Under such circumstances characteristic racial
and temperamental differences appear that would otherwise pass entirely
unnoticed.

When the physical unity of a group is perpetuated by the succession of
parents and children, the racial temperament, including fundamental
attitudes and values which rest in it, is preserved intact. When,
however, society grows and is perpetuated by immigration and adaptation,
there ensues, as a result of miscegenation, a breaking up of the complex
of the biologically inherited qualities which constitute the temperament
of the race. This again initiates changes in the mores, traditions, and
eventually in the institutions of the community. The changes which
proceed from modification in the racial temperament will, however,
modify but slightly the external forms of the social traditions, but
they will be likely to change profoundly their content and meaning. Of
course other factors, individual competition, the formation of classes,
and especially the increase of communication, all co-operate to
complicate the whole situation and to modify the effects which would be
produced by racial factors working in isolation.

III. INVESTIGATIONS AND PROBLEMS

1. Conceptions of Human Nature Implicit in Religious and Political
Doctrines

Although the systematic study of it is recent, there has always been a
certain amount of observation and a great deal of assumption in regard
to human nature. The earliest systematic treatises in jurisprudence,
history, theology, and politics necessarily proceeded from certain more
or less naive assumptions in regard to the nature of man. In the
extension of Roman law over subject peoples the distinction was made
between _jus gentium_ and _jus naturae_, i.e., the laws peculiar to a
particular nation as contrasted with customs and laws common to all
nations and derived from the nature of mankind. Macauley writes of the
"principles of human nature" from which it is possible to deduce a
theory of government. Theologians, in devising a logical system of
thought concerning the ways of God to man, proceeded on the basis of
certain notions of human nature. The doctrines of original sin, the
innate depravity of man, the war of the natural man and the spiritual
man had a setting in the dogmas of the fall of man, redemption