"As a face is reflected in water,
so the heart reflects the real person"
If the heart reflects the real person, what reveals the heart? Consider applying "the waiter test." Look at how a person treats a waiter. If a waiter spills water on him, how does he react? Does he kindly say, "It's okay, the water will dry," or does he make a big scene? If you're trying to discern someone's character, observe how he or she treats "unimportant" people, especially in moments of frustration. You'll learn a lot about that person's true heart.