What have I always believed? That on the whole, and by and large, if a man lived properly, not according to what any priests said, but according to what seemed decent and honest inside, then it would, at the end, more or less, turn out all right.

The speaker affirms a plain, humanist moral creed: live by an inner sense of decency and honesty rather than by external religious authority. The phrasing (“on the whole, and by and large”) signals a pragmatic, non-dogmatic ethics—less about metaphysical certainty than about how people actually behave and what tends to follow from it. The final clause (“it would…turn out all right”) suggests faith in moral causality or at least in the long-run value of integrity, even amid ambiguity and imperfect outcomes. In Pratchett’s work, this kind of sentiment often underwrites a satire of institutions (including organized religion) while defending everyday kindness and personal responsibility as the real foundations of a good life.