Theory

Supposition or system of ideas intended to explain something

A theory is, in general, a set of propositions or ideas about something, developed in a variety of ways through any sort of reasoning. This includes informal folk psychological theories of why someone behaves the way they do, scientific theories that attempt to explain some phenomenon, philosophical theories (for example of politics or the nature of reality), and a range of other uses. Not all theories are equal and they may, for example, be compared in terms of how well they explain a phenomenon and the strength of evidence for and against them.

From Wikipedia, under CC BY-SA. More on occurri.