Disquotational principle
The disquotational principle is a philosophical principle which holds that a rational speaker will accept "p" if and only if they believe p. The quotes indicate that the statement p is being treated as a sentence, and not as a proposition. This principle is presupposed by claims that hold that substitution fails in certain intensional contexts. Overview Consider the following argument: (1) Sally accepts the assertion that "Cicero was a famous orator" while dissenting from the assertion that "Tully was a famous orator". (2) Cicero is Tully Therefore, (3) Sally believes that Tully was a famous orator. To derive (3), we have to assume that when Sally accepts that "Cicero was a famous orator", she believes that Cicero was a famous orator. Then we can exchange Cicero for Tully, and derive (3). Bertrand Russell thought that this demonstrated the failure of substitutivity of identicals in intensional contexts. In "A Puzzle about Belief," Saul Kripke argues that the application of the disquotational theorem can yield a paradox on its own, without appeal to the substitution principle, and that this may show that the problem lies with the former, and not the latter. There are various formulations of this argument. Suppose that,