Some Limits of Logical Predictivism

Abstract

In the traditional epistemology of logic, there is a consensus that the justification of logical principles differs from the justification of other fields of inquiry. In this sense, logical evidence possesses a basic and a priori character, which makes it exceptional. In contrast to this position, a view in the philosophy of logic, designated as anti-exceptionalism about logic (AEL), claims that logic isn’t exceptional, it doesn’t have a special epistemic or methodological status in relation to other sciences. According to AEL, logic could borrow methods of theory choice from the sciences. According to AEL, logic could borrow methods of theory selection from science. In this regard, the anti-exceptionalist view of logical predictivism will be presented. This position indicates that logical theories are justified based on their predictive success and explanatory power. In this paper, it will be argued that logical predictivism faces some limitations: 1) by adopting a priori evidence, logical predictivism not only breaks with one of the central theses of the anti-exceptionalist approach - which proposes a rapprochement between the epistemology of logic and the empirical sciences - but also fails to offer a new epistemological alternative for logic; 2) the deduction of theorems is not equivalent to making predictions; and 3) in logical predictivism, there is an interdependence between the metaphysical and epistemological varieties of AEL.