Q: What’s the difference between Derrida and his critics?
A: Derrida says there is nothing outside the text. His critics say there is nothing inside his texts either.

Q: What’s the difference between Heidegger and Carnap?
A: Heidegger believed that his writings contain thoughts about Nothing, whereas Carnap believed that they contain thoughts about nothing.

Q: What’s the difference between Heidegger, Sartre and Foucault?
A: It’s just narcissism of small differences. All of them extolled the value of freedom (in theory), but in practice they all fell in love with various forms of totalitarianism. Heidegger supported Hitler, Sartre supported Stalin, and Foucault supported Khomeini.