n.
1.
Origin, source, cause, original cause, spring, mainspring, fountain, groundwork, prime mover, fountain-head.
2.
Element, substratum, fundamental or primordial substance.
3.
Postulate, axiom, maxim, law, elementary proposition, fundamental truth.
4.
Doctrine, tenet, dogma, opinion, rule of action, law of conduct.
5.
Ground, motive, reason.
6.
Integrity, uprightness, rectitude, probity, honesty, virtue, righteousness, incorruptibility, goodness, trustworthiness, trustiness, worth, honor.
7.
Faculty, power, endowment of the soul.