WHY MODELS RATHER THAN RULES GIVE A BETTER ACCOUNT OF PROPOSITIONAL REASONING - REPLY

O'Brien, Braine, and Yang argue that the mental model theory of propos itional reasoning is easy to refute, and they report 3 experiments tha t they believe falsify the theory. In contrast, Bonatti argues that th e model theory is too flexible to be falsified. We show that O'Brien e t al.'s experiments do not refute the model theory and that Bonatti's claims are ill founded. Formal rule theories of propositional reasonin g have 3 major weaknesses in comparison with the model theory: (a) The y have no decision procedure; (b) they lack predictive power, providin g no account of several robust phenomena (e.g., erroneous conclusions tend to be consistent with the premises); and (c) as a class of theori es, they are difficult to refute experimentally.