Which preposition to use with propounder

of Occurrences 8%

In a later review, Hunt is a propounder of atheism.

in Occurrences 1%

" It is evident that the defect which Socrates complains of respecting Anaxagoras' doctrine does not concern the principle itself, but the shortcoming of the propounder in applying it to nature in the concrete.

Which preposition to use with  propounder