CHAPTER XXI

THE RELATIVE IMPORTANCE OF TRADITION AND HEREDITY 437

(1) Definite conclusions are difficult to reach. (2) History in

the intermediate period was due to germinal change. (3) The

natural endowment of America, (4) Asia, (5) Africa, (6) and of

other regions, (7) and their geographical features, (8) suggests

that history in the subsequent periods was chiefly of the nature

of traditional change. (9) Though germinal changes are important

they do not account for the outstanding events, though they have

contributed to them. (10) Lesser germinal changes colour

tradition, but are not determining factors in history. (11)

Known germinal changes, such as those produced by crossing, are

less important than accompanying traditional changes, (12) of

which there are many instances in the third period. (13) The

direct effect of the environment is not negligible, and has

influenced the course of history. (14) The cyclic course of

civilization, which has been attributed to germinal change, is

in the main due to traditional changes. (15) Tradition at the

present day overlays the manifestation of mental characters in

so great a degree that (16) differences between classes may well

seem wholly traditional, but (17) psychological tests and (18)

other evidence show that innate mental differences are present,

(19) though it is difficult to appraise their value and the

importance of modern differential fertility.

The population problem · 第 21 / 32 章