bands have but one wife; thence to the form in which the
husbands are related; and finally to the form in which they are brothers
only, as in the fraternal polyandry of the ancient Britons. It is almost
needless to point out that, as in passing from promiscuity to polyandry
the domestic relations become more coherent and definite, so do they in
passing from the lower forms of polyandry to the higher. That polygyny
is better than polyandry may be concluded from its effects. It conduces
in a higher degree to social self-preservation than the inferioi types
of marital relations by making possible more rapid replacement of men
lost in war, and so increases the chance of social survival. By
establishment of descent in the male line it conduces to political
stability; and, by making possible a developed form of ancestor-worship,
it consolidates society.

MONOGAMY

Societies which from generation to generation produce in due abundance
individuals who relatively to the requirements are the best physically,
morally, and intellectually, must become the predominant societies, and
must tend through the quiet process of industrial competition to replace
other societies. Consequently, marital relations which favour this
result in the highest degree must spread; while the prevailing
sentiments and ideas must become so moulded into harmony with them that
other relations will be condemned as immoral. The monogamic form of the
sexual relations is manifestly the ultimate form; and any changes to be
anticipated must be in the direction of completion and extension of it.

_II.--Political Organisation_

A society is formed only when, besides juxtaposition there is
co-operation. Co-operation is made possible by society and makes society
possible. It pre-supposes associative men; and men remain associated
only because of the benefits co-operation yields them. But there cannot
be concerted actions without agencies by which actions are adjusted in
their times, amounts, and kinds; and the actions cannot be of different
kinds without the co-operators undertaking different duties. That is to
say, the co-operators must become organised, either voluntarily or
involuntarily.

AGGREGATION

The political evolution manifested by increase of mass is political
aggregation. One of the laws of evolution at large is that integration
results when like units are subject to the same force or the like
forces; and from the first stages of political in