Especially in times of the pursuance and killing of people of a different faith or of different ideas by fanatic Islamists on the one side and equally fanatic fascists on the other side Voltaire’s text is more important than ever.

No philosopher has fought for this ideal more than the French Enlightenment thinker Voltaire. His treatise “Über die Toleranz” is a timeless document that shows how important religious moderation is. It is a plea for humility against megalomania, and for humanity against dogmatism. Wherever religious fanaticism occurs Voltaire is having none of it:

„Mensch, du erhebst dich über Gott, wo du andere Menschen aufgrund ihres Glaubens richtest.“

Unfortunately he does not speak about non-religious fundamentalism which is based on class, race or a nation at all in his treatise and that certainly is a major shortcoming from the vantage point of the present.

Voltaire’s text is a reaction to the religiously motivated judicial murder of the Protestant merchant Johann Calas. Voltaire, who was mainly known in well-educated parts of society before he published this treatise, became very popular with the masses with his text. His text is not – as some people assumed – an attack on or a plan to abolish Catholicism (even though he seems to have a slight preference for eastern philosophies) his interest lies in a tolerant, enlightened spirituality.

His text was the main reason that Johann Calas was posthumously rehabilitated and the legal scandal publicly denounced. Voltaire continued the tolerance discourse of the Enlightenment which was amongst others triggered by John Locke.

Which philosophical texts would you recommend?

Check out Hannah Arendt’s “Die Freiheit frei zu sein“, Steven Pinker’s „Enlightenment Now“ and Manfred Geier’s „Aufklärung – Das europäische Projekt“