RATIONALITY IS SURVIVAL: Why belief in Santa Claus can be more rational than disbelief; why we never know what is a priori rational.
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Consider religious dietary laws. They may seem irrational to an observer who sees purpose in things and defines rationality in terms of what he can explain. Actually they will most certainly seem so. The Jewish Kashrut prescibes keeping four sets of dishes, two sinks, the avoidance of mixing meat with dairy products or merely letting the two be in contact with each other, in addition to interdicts on some animals: shrimp, pork, etc.
These laws might have had an \textit{ex ante} purpose. One can blame insalubrious behavior of pigs, exacerbated by the heat in the Levant (though heat in the Levant was not markedly different from that in pig-eating areas further West). But it remains that whatever the purpose, the Kashrut survived $\approx$ three millennia not because of its \textit{rationality} but because the populations that followed it survived. It brought cohesion: people who eat together hang together. Simply it aided those that survived because it is a convex heuristic (see our definition of convex heuristic in \ref{convheu}). Such group cohesion might be also responsible for trust in commercial transactions with remote members of the community. Simply, people who eat together hang together and dietary laws help in enforcing a group cohesion.
This adumbrates our central idea: that rationality is not what has conscious verbalistic explanatory factors; it only be what aids survival, avoids ruin. Rationality is risk management, period.
The consequence is that beliefs should not be judged on whether they are epistemologically true or false, but primarily in whether they allow survival [IN THE COLLECTIVE, and IN THE LINDY SENSE]. Belief in Santa Claus is therefore rational if it prevents people from dying and not rational if they cause extinction.
Take the idea to its logical conclusion. Superstitious-like resistance to matters like GMOs might be the instrument of enforcing such survival.
www.fooledbyrandomness.com/rationality.pdf
via RATIONALITY IS SURVIVAL: Why belief in Santa… – Nassim Nicholas Taleb.
