Principle
Part of speech: noun
Definition: A fundamental assumption. A rule used to choose among solutions to a problem. Moral rule or aspect. A rule or law of nature, or the basic idea on how the laws of nature are applied. A fundamental essence, particularly one producing a given quality. A beginning.
Example sentence: The strongest principle of growth lies in the human choice.
Precept
Part of speech: noun
Definition: A rule or principle, especially one governing personal conduct.
Example sentence: There is no moral precept that does not have something inconvenient about it.