  This work studies the impact of economic inequality on the evolution of
intolerance through a reputation-based model of indirect reciprocity. Results
show that economic inequality is a powerful enhancer of intolerance, inducing
the escalation of out-group discrimination even without the presence of new
intolerant mutants. It also generates behavior modifications within tolerant
disfavored minorities: their members either relax punishments against the
uncooperative or prioritize helping the wealthy, even suffering discrimination
in return. On the other hand, the redistribution of wealth is proved as a
viable solution to avoid the spread of intolerance as long as it increases
equality and is implemented before intolerance permeates part of the
population.
