Van Fraassen meets Popper: Logical relations and cognitive abilities

Van Fraassen, like Popper before him, assumes that confirmation and disconfirmation relations are logical relations and thus hold only among abstract items. This raises a problem about how experience, for Popper, and observables, for van Fraassen, enter into epistemic evaluations. Each philosopher offers a drastic proposal: Popper holds that basic statements are accepted by convention; van Fraassen introduces his “pragmatic tautology.” Another alternative is to reject the claim that all evaluative relations are logical relations. Ayer proposed this option in responding to Popper, as did Sosa in a different context. I argue that this option should be pursued and propose a line of research that the option suggests.