What is the term for the methodical exploration of nature and the logical explanation of the observations?

Question

anonymous · Answer

Rationality?  Natural philosophy?  You can't say "science" because your prescription lacks one absolutely key ingredient, which is that those logical explanations must be verified repeatedly by empirical observation to be considered anything other than unproven speculation.

Aristotle and Ptolemy methodically explored nature and made logical explanations of their observations -- logical explanations which were, however, wrong.  For that matter, so did medieval theologians.

What distinguishes "science" from "just using your head" is the reliance on experiment, and the rejection of theories, no matter how logical or satisfying, if they are not consistent with experiment.