Honesty is a principle. Service is a principle. Love is a principle. Hard work is a principle. Respect, gratitude, moderation, fairness, integrity, loyalty, and responsibility are principles. There are dozens and dozens more. They are not hard to identify. Just as a compass always points to true north, your heart will recognize true principles.
Sean Covey (2014). “The 7 Habits of Highly Effective Teens”, p.24, Simon and Schuster