able to break the mold and transition toward inclusive
institutions. Our explanation for these transitions is
historical, but not historically predetermined. Major
institutional change, the requisite for major economic
change, takes place as a result of the interaction between
existing institutions and critical junctures. Critical junctures
are major events that disrupt the existing political and
economic balance in one or many societies, such as the
Black Death, which killed possibly as much as half the
population of most areas in Europe during the fourteenth
century; the opening of Atlantic trade routes, which created
enormous profit opportunities for many in Western Europe;
and the Industrial Revolution, which offered the potential for
rapid but also disruptive changes in the structure of
economies around the world.
Existing institutional differences among societies
themselves are a result of past institutional changes. Why
does the path of institutional change differ across
societies? The answer to this question lies in institutional
drift. In the same way that the genes of two isolated
populations of organisms will drift apart slowly because of
random mutations in the so-called process of evolutionary
or genetic drift, two otherwise similar societies will also drift
apart institutionally—albeit, again, slowly. Conflict over
income and power, and indirectly over institutions, is a
constant in all societies. This conflict often has a contingent
outcome, even if the playing field over which it transpires is
not level. The outcome of this conflict leads to institutional
drift. But this is not necessarily a cumulative process. It
does not imply that the small differences that emerge at
some point will necessarily become larger over time. On
the contrary, as our discussion of Roman Britain in chapter
6 illustrates, small differences open up, and then
disappear, and then reappear again. However, when a
critical juncture arrives, these small differences that have
emerged as a result of institutional drift may be the small
differences that matter in leading otherwise quite similar
societies to diverge radically.
We saw in chapters 7 and 8 that despite the many
similarities between England, France, and Spain, the
critical juncture of the Atlantic trade had the most
transformative impact on England because of such small