Peter Susanszky

The adoption question asks whether there are logical rules that cannot be adopted if one does not already infer in accordance with them. Several philosophers, most famously Saul Kripke and Romina Padró, agree that there are such rules. Accordingly, they agree that there is an adoption problem. However, there is disagreement over which rules are unadoptable. In particular, while most agree that if there is an adoption problem, modus ponens and universal instantiation are in its scope, many would exclude adjunction from the list. In this paper, I argue that adjunction is in the scope of the adoption problem. Then I show that the most straightforward counterargument against adjunction being in the scope of the problem, which tries to reformulate the adjunction rule into a more palatable one, does not work.