Voltaire made fun of the ontological argument in his novel Candide.

Voltaire

A pseudonym for François-Marie Arouet, an Enlightenment writer, historian, and philosopher famous for his advocacy of freedom of speech, religious tolerance, and separation of church and state.

Ontological Argument

An argument (or set of arguments) that tries to prove the existence of God from the very concept of “God.” For example: God, by definition, is that Being with all possible perfection; existence is a perfection; therefore God exists.