No taboos exist for liberalism. For Liberals, any state of affairs is open for discussion and any opinion worthy of dispute. Liberalism therefore automatically desanctifies any subject which people with vested interests try to keep out of the general debate with spurious arguments. Any political and social progress starts with a deviation from established wisdom. In the eyes of Liberals, anyone who bans deviating ideas and persecutes the critical denial of the established wisdom as heresy hampers social and political progress.
Karl-Hermann Flach: Noch eine Chance fur die Liberalen (“Still A Chance for the Liberals”), Frankfurt a.M. 1971