I examine Paul Boghossian's recent attempt to argue for scepticism about logical rules. I argue that certain rule-and proof-theoretic considerations can avert such scepticism. Boghossian's ‘Tonk Argument’ seeks to justify the rule of tonk-introduction by using the rule itself. The argument is subjected here to more detailed proof-theoretic scrutiny than Boghossian undertook. Its sole axiom, the so-called Meaning Postulate for tonk, is shown to be false or devoid of content. It is also shown that the rules of Disquotation and of Semantic Ascent cannot be derived for sentences with tonk dominant. These considerations deprive Boghossian's scepticism of its support.