3.3 diffusion
Diffusion is a phenomenon long observed in the social sciences.15 The mechanism for
these patterns is often ill-defined, both theoretically and empirically. It can be difficult
to distinguish among imitation, learning, socialization, herd behavior, contagion, or any
of the other commonly named drivers of diffusion, as many of those mechanisms generate
similar predictions about how individuals would behave in the face of a fad.
One probable mechanism for the adoption of the flat tax is rational learning. In
rational learning, individual countries’ policies can converge on “a promising foreign model
... [through which] systematic, thorough cost-benefit analysis demonstrates its superiority
over established policies.”16 This is the bedrock of the rational choice perspective, that
individuals make informed judgements about their options, and through calculating their
payoffs in all circumstances move toward the least painful one. In the laboratory of reform
in postcommunist Europe, policymakers could learn from other countries’ successes and
failures. After observing the success of the flat tax in attracting FDI and encouraging
tax collection, policymakers facing similar pressures would move to adopt the tax.
Governments in the post-communist countries borrowed shamelessly from the suc-
cesses of other countries. Not just international organizations but also NGOs promoted
this practice, through umpteen cross-border conferences that highlighted transition suc-
cesses and failures, as well as exchange programs that put ministers and policymakers in
15For just a few examples, see Case & Katz (1991) on how, for example, criminal activity and drug
abuse patterns tend to be replicated within neighborhoods, as a result of “collective socialization” and
“contagion”; Gleditsch & Ward (2006) on democratic diffusion; Gleditsch 2003 on civil wars; Brune &
Guisinger (2003) on capital-account openness; Finnemore & Sikkink (1998) and Cortell & Davis (1996)
on the spread of international norms; Rogers 1962 on the spread of innovations; Orenstein (2003) on
the spread of pension reforms; Berry and Berry (1990), and Volden and Shipan (2006), on the spread
of lotteries and anti-smoking policies in U.S. states, respectively; Simmons & Elkins (2004) on the
international spread of liberalization; Lutz & Sikkink (2000), Sikkink & Walling (2006), and Kim (2005),
on “cascades” in justice (holding heads of state accountable for past abuses)
16Weyland (2005) p. 271.
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