The evolutionary interpretation of history can be understood as a set of interconnected sagas. For example, Boulding describes the rise of agriculture as the product of increasing populations tending to organize into settlements, which allowed gathers to observe that last year's discarded seeds tended to produce new plants. This saga focuses on the ways in which energy and materials are used to convert knowledge into artifacts. At the same time the knowledge available at any time is shaped by the tools of learning available at that time. Decision making and choices play a greater role in societal evolution than in biological evolution.
Decisions imply the power and freedom to change the future.
Boulding considers whether human history is determined or random. That is, the basic dynamics of power are not changed, but the players and their roles may be changed. Boulding identifies three general types of human power, corresponding to the threat, exchange and integrative systems. In society these forms of power interact, opposing or reinforcing each other, and are very rarely found in pure form. Boulding also explores the dynamics of evolution.