Basic beliefs of positivist philosophy include: 1. Scientific knowledge must be based on empirically testable data. Thus, any scientific claim must be empirically verifiable. If any claim is not empirically verifiable, then it must be non-scientific, or even meaningless. 2. Empirical observations must be generalized and expressed as universal laws. Thus, observations must be reformulated as mathematical expressions, most often in statistical formulations. 3. There must be a unity of method across all sciences. Thus, there is no significant difference between the natural sciences and the social sciences. The correct answer is E.