Sartre, Nothingness, and Difference

It can be wondered why Sartre did not write a book called 'Sameness and Difference', rather than Being and Nothingness. After all, Plato demonstrates that Nothing is no more than an abstraction from Difference, the correlate of which is Sameness. However, it is unclear that Plato's passively borne idea of Difference can account for either Sartre's dynamic Nothingness or the Freedom that is one of its modes. On the other hand, Deleuze and Derrida have shown how Difference can be dynamic, and Formaterialism, here, has derived Freedom from Difference. So, Sartre's inattention to Difference, seems, at minimum, Philosophically negligent. But, perhaps a clue to justifying the exclusivity of his focus on Nothingness might be that his Marxist orientation, as a matter of biographical fact, precedes his acquaintance with Phenomenology and Existentialism. On that basis, in contrast with the common interpretation that after Being and Nothingness, he surprisingly morphs from an Existentialist to a Marxist, that work can be understood as a Marxist project, wittingly or otherwise, all along. As such, it is less surprising that one of the targets of Being and Nothingness is a traditional Marxist target, namely 'idealist' Hegelianism, in which case one of its specific targets is the Hegelian 'idealist' notion of 'Nothingness'. Being and Nothingness can thus be understood as presenting an anti-Hegelian 'materialist' theory of Nothingness, with respect to which even Platonic Difference is a peripheral issue.