Tenet
Tenet , noun
[Latin tenet he holds, from tenere to hold. See Tenable.]
Any opinion, principle, dogma, belief, or doctrine, which a person holds or maintains as true; as, the tenets of Plato or of Cicero.
That al animals of the land are in their kind in the sea,... is a tenet very questionable.
The religious tenets of his family he had early renounced with contempt.