1) Feyerabend’s “Intelligibility” (1948) anticipates key aspects and arguments articulated in AGAINST METHOD (1976).
2) The argument against the criterion of intelligibility is a precursor to his argument against the stability thesis (so we could call it the “intelligibility thesis”).
3) He is arguing against it not only on historical grounds (historical approach) but also on methodological grounds (against conceptual conservatism).
4) The possibility to violate the requirement of “intelligibility”, in the sense of the imposed norm of a familiar model is a precursor to the possibility of incommensurability.
5) Key aspects of Feyerabend’s philosophy normally ascribed to his “Popperian” phase were developped before coming under Popper’s influence, even if the terminology is not yet the same.
6) An interesting example of this is Feyerabend’s favourable use of “positivism” in conjunction with realism, whereas in his immediately succeeding articles he opposes the two. This suggests that “Intelligibilty”‘s ideas developped under Kraftian influence, and that Feyerabend later reformulated them in Popperian terminology.
7) When Feyerabend “re-writes” his past he is speaking as a philosopher and not as a petulant or cynical or self-deluded little Oedipus. His later de-emphasising of Popper’s role in his development is first and foremost a case of reconceptualisation.
8) To consider that Feyerabend’s ideas on incommensurability were an “extension” of Popper’s ideas, one should refer to Feyerabend’s concept of an “extension”, as he found it used in a talk by Niels Bohr that he attended. This Bohrian use of “extension” is close kin to Feyerabend’s concept of incommensurability.
9) Philosophers often use “conceptual personae”, figures or persons that are not
treated empirically but as symbols of modes of thought and forms of life. Feyerabend is very clearly a philosopher of this type. I see no reason to disbelieve the late Feyerabend when he says that behind and underwriting his fascination for Popper there was the figure of Mach (amongst others), even if he was unaware of it at the time. Nietzsche and Jung (two understated but important influences for Feyerabend) describe similar processes, and they are frequent in everyone’s life. Popper (the flesh-and-blood, empirical Popper) could well have functioned as such a symbol at the time that they were frequenting each other.
10) Reconceptualisation is not “distortion” or mis-representation, but, potentially, a step closer to reality.