Abstract

I distinguish a priori knowledge from a priori truths or statements. A priori knowledge either is evident or is derived from evident premisses by means of correct reasoning. An a priori statement is one that reflects features of the conceptual framework within which it is placed. The statement either describes semantic relations between concepts of the framework or it characterizes the application of the framework to experience and the world. An a priori statement is not necessarily part of anyone’s a priori knowledge. I also distinguish empirical knowledge from empirical statements. Both statements and theories are empirical if they are designed to characterize features of experience and the world. Knowledge is empirical if it fits experience; thus, one must check to see whether it fits. We do not obtain knowledge of logical systems by rational insight of evident truths and careful deductions from evident truths. Adequate logical systems are developed by trial and error. Logical knowledge is empirical knowledge that is not generally a priori. It is empirical knowledge of a priori truths and principles of our conceptual systems. Logical systems are empirical theories of these truths and principles.