Althusser called a recent essay: ‘Is it simple to be a Marxist in philosophy?’ My title, intentionally provocative, echoes that question. Following Althusser, I shall answer it in the negative and, in so doing, shall raise a series of further questions concerning the nature of and connections between politics, science and philosophy. My lecture will keep turning on these three points, just as Althusser's own work has turned on them, ever since his first book, a monograph on Montesquieu, up to his most recent critical interventions on the role and organization of the French Communist Party in the 1970s. In an interview given in 1968, characteristically entitled ‘Philosophy as a revolutionary weapon’, Althusser linked the three points in an autobiographical comment:
In 1948, when I was thirty, I became a teacher of philosophy and joined the French Communist Party. Philosophy was an interest; I was trying to make it my profession. Politics was a passion; I was trying to become a communist militant.