Xenophobia is really that: a (rational) fear of the stranger

A definition of xenophobia is provided. It is argued that basic economics may produce a general theory of it, and that a basic tenet of behavioural economics, i.e. risk aversion, may explain an important class of specific cases of xenophobia. A typical persona oeconomica is risk-averse, hence s/he will fear the changes in social norms that an influx of alien people will induce. Social norms are ubiquitous, yet their relevance and the matters...