Sidgwick, Reflective Equilibrium and the Triviality Charge

I argue against the claim that it is trivial to state that Sidgwick used the method of wide reflective equilibrium. This
claim is based on what could be called the Triviality Charge, which is pressed against the method of wide reflective
equilibrium by Peter Singer. According to this charge, there is no alternative to using the method if it is interpreted
as involving all relevant philosophical background arguments. The main argument against the Triviality Charge is
that although the method of wide reflective equilibrium is compatible with coherentism (understood as a form of
weak foundationalism) as well as moderate foundationalism, it is not compatible with strong foundationalism.
Hence, the claim that a philosopher uses the method of wide reflective equilibrium is informative. In particular,
this is true with regard to Sidgwick.