Twin substances abuse: Pap and Kuhn against the distinction between essential and accidental proprieties of scientific kinds




In this paper I give a critical assessment of the essentialism about natural kinds using the functional theory of the a priori by Arthur Pap (1943, 1944 & 1946). In a manner similar to authors that uphold the primacy of scientific practice, reasons are given to reject the legitimacy of a distinction between essential and accidental proprieties inside of a scientific theory. We aim to show how an answer very similar to Thomas Kuhn’s to the famous Twin Earth experiment can be formulated using Pap’s functional theory. Both Kuhn and Pap give reasons to reject the causal theory of reference to the scientific lexicon. Having as basis an analysis of scientific practice from the first half of 20th century, we show how the distinction between accidental and essential proprieties is inadequate (the case of the “Twin Phosphorus”). This allows us to bring together the functional theory of the a priori and the “historical turn” in Philosophy of Science found in authors like Kuhn, showing also how this process was more continuous than originally thought.

Author Biography

Jeferson Diello Huffermann, UFRGS

Doutorando do PPG Filsofia UFRGS


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