  The ability to learn from others (social learning) is often deemed a cause of
human species success. But if social learning is indeed more efficient (whether
less costly or more accurate) than individual learning, it raises the question
of why would anyone engage in individual information seeking, which is a
necessary condition for social learning's efficacy. We propose an evolutionary
model solving this paradox, provided agents (i) aim not only at information
quality but also vie for audience and prestige, and (ii) do not only value
accuracy but also reward originality -- allowing them to alleviate herding
effects. We find that under some conditions (large enough success rate of
informed agents and intermediate taste for popularity), both social learning's
higher accuracy and the taste for original opinions are evolutionary-stable,
within a mutually beneficial division of labour-like equilibrium. When such
conditions are not met, the system most often converges towards mutually
detrimental equilibria.
