Feyerabend and Badiou agree on many fundamental ideas. For example, for both knowledge and method belong to the domain of representation, although “truth” in Badiou’s sense does not. Truth is knowledge in the making, and there is no method there, only fidelity (what Feyerabend calls “tenacity”).
Feyerabend and Badiou are both pluralists, espousing an ontology of multiplicities. They are pluralists without being relativists. Feyerabend says “each particular culture is potentially all cultures”, enouncing all the universality and eternity that Badiou needs. Badiou tells us explicitly that “truth is universal”, but that this is not the universality of the universal quantifier. Universal means reactivable in other contexts, and this is what Feyerabend has always argued for.
Badiou’s conception of the difference between truth and knowledge can viewed through the spectacles of the distinction between science in the making and science made, or or that of the context of discovery and the context of justification. Feyerabend partially accepts this distinction, and privileges the context of discovery, but then deconstructs it by means of the notion of exchange and encounter, what one may call the context of participation, or the “context of immanence”.