  In recent years, criticism of the methodology of particle physics beyond the
Standard Model has increased, diagnosing too much reliance on aesthetic
criteria for theory development and evaluation. Faced with several decades of
experimental confirmation of all theories lacking, we subject four aesthetic
criteria - simplicity, symmetry, elegance, and inevitability -, regularly
mentioned in theory evaluation, to critical examination. We find that these
criteria, all of which can be reduced to a desire for simplicity, have
repeatedly misled modern particle physics. This is largely due to the lack of
metatheoretical permanence of a uniform conception of simplicity. The
reductionist claim of particle physics - the search for simple fundamental
principles in a complex world - will be worked out as the reason why this
discipline is particularly susceptible to the aesthetic appeal of simplicity.
Thus, compared to disciplines dealing with complex phenomena, aesthetic
criteria are much more frequently applied, exposing particle physics to the
risk of missteps and dead ends.
