I would replace the quality of sincerity with honesty, since one can hold a conviction sincerely without examining it, while honesty would require that one subject one's convictions to frequent scrutiny.

It is not enough to have the courage of your convictions, you must also have the courage to have your convictions challenged.

I would replace the quality of sincerity with honesty, since one can hold a conviction sincerely without examining it, while honesty would require that one subject one's convictions to frequent scrutiny.