With the exception of Nietzsche, no other madman has contributed so much to human sanity as has Louis Althusser. He is mentioned twice in the Encyclopaedia Britannica merely as a teacher. Yet for two important decades (the 1960s and the 1970s), Althusser was at the eye of all the important cultural storms. He fathered quite a few of them.
Althusser observed that society consists of practices: economic, political and ideological. He defines a practice as: