Abstract

Knowledge is distinguished between knowledge about the relations of ideas, like mathematical truths and logic, and knowledge of matters of fact or empirical knowledge of the world, which is derived from “sense experience.” Observational sentences are based on sense experience and can sometimes be judged to be true or false. Thus, the possibility of errors in observational judgment must be allowed. We can acknowledge the existence of observational error in general, and even be unable to specify any particular observation statement that is certain, and yet be able to accept most observation statements on the basis of the corresponding reports and to reject others.