The Constitutive A Priori and the Structure of Physical Knowledge

Paul L. Franco, University of Pennsylvania


My dissertation aims to answer two questions: first, what does it mean for certain elements of knowledge to be constitutive of the possibility of physical knowledge and how is it connected to a priority? Second, given that constitutive elements can be abandoned and new ones adopted in response to logical, mathematical, and physical findings, what distinguishes them from mere empirical statements? In answering these questions, I claim that physical knowledge is made possible by certain a priori elements of knowledge that provide the criteria for making well-formed, precise, and determinate empirical statements about objects, their behavior, and their relationships in space and time. Without the framework provided by constitutive a priori elements, meaningful, scientific knowledge of the physical world is impossible.

The main claim, guiding questions, and methodology of my dissertation have deep historical roots. After identifying in chapter one Kant’s major methodological contribution to the study of the structure of physical knowledge, chapters two and three show how Hans Reichenbach and C.I. Lewis modify Kant’s account in direct response to the developments in relativity theory, mathematics, and logic. Next, I consider objections to these accounts raised by W.V. Quine.

In chapters four and five I show how Quine’s objections can be answered. First, I show that Rudolf Carnap – the ostensible target of Quine’s criticisms – offers an account of the distinction between the a priori and the empirical that is not grounded in a commitment to the analytic/synthetic distinction. Second, I show the ways in which Michael Friedman’s contemporary account challenges Quine’s claim that his account better captures the structure of physical knowledge. I also highlight certain problems with Friedman’s semantic account of constitutivity.

Finally, in the last chapter, I synthesize the past insights of the Neo-Kantian theories of the structure of physical knowledge to arrive at an account of the objectivity of physical knowledge. I explain the importance of the pragmatic and epistemological – rather than merely semantic – roles of the a priori in relation to the objects of physical knowledge and suggest that objectivity is tied directly to the satisfaction of pragmatic criteria.