1. only phenomena and hence knowledge confirmed by the senses can genuinely be warranted as knowledge (the principle of phenomenolism).
2. The purpose of theory is to generate hypotheses that can be tested and that will thereby allow explanations of laws to be assessed (the principle of deductivism).
3. Knowledge is arrived at through the gathering of facts that provide the basis for laws (the principle of idsuctivism).
4. Science must (and presumably can) be conducted in a way that is value free (that is, objective).
5. There is a clear distinction between scientific statements and normative statements and a belief that the former are the true domain of the scientist. This last principle is implied by the first because the truth of otherwise of normative statements cannot be confirmed by the senses.