Raymond Aron ascribes to Weber the view that 'each man's conscience is irrefutable.' ... while [Weber] holds that an agent may be more or less rational in acting consistently with his values, the choice of any one particular evaluative stance or commitment can be no more rational than any other. All faiths and all evaluations are equally non-rational.
"After Virtue". Book by Alasdair MacIntyre, 1981.