theory

a tentative insight into the natural world; a concept that is not yet verified but that if true would explain certain facts or phenomena

“a scientific hypothesis that survives experimental testing becomes a scientific theory”

a belief that can guide behavior

“the architect has a theory that more is less”

a well-substantiated explanation of some aspect of the natural world; an organized system of accepted knowledge that applies in a variety of circumstances to explain a specific set of phenomena

“true in fact and theory”