synergy: Processes in which causal factors mutually enhance their combined
impact so as to have a greater effect than they might have had on their own.
tectonic margins. See margins, tectonic.
tectonic plates: Portions of the Earth’s surface or crust that move as a result
of movements in the hot, semiliquid magma beneath them.
teosinte: Wild, ancestral form of maize.
thermodynamics, ¿ rst and second laws of: Two fundamental laws of
modern physics; the ¿ rst law of thermodynamics says that energy is never
lost; the second law says that “free energy,” i.e., energy distributed in ways
that enable it to do work, is slowly dissipated over time as energy differentials
tend to even out.
tribute-taking societies: Societies dominated by tribute-taking states,
in which the majority of people are small farmers; such societies are
characterized by lower rates of innovation than the much more commercialized
“capitalist” societies.
tribute-taking states (tribute-takers): States or groups capable of exacting
resources from others, if necessary, through the threat of force.
universal Darwinism: Term coined by Richard Dawkins to suggest that
change in many different domains, including cosmology and history, is
similar to change through natural selection in the biological domain.
universal history: The project of constructing histories at all scales; a
project pursued at least since the classical era, sometimes used as a synonym
for “big history.”
wage labor: Work performed in return for wages rather than under obligation
or compulsion.
world history: Historical research and teaching embracing the entire world,
generally focusing on the last 10,000 years of human history.