by Patrick Appel
The phrase has rules, as Ben Casnocha notes:
Someone who credibly says "I'm proud of you" usually has two characteristics. First, he is probably higher status / higher power. Most of the time, having pride about someone else comes from a place of superiority. Second, he must know you well. Most of the time, to be proud of someone means you know where they've been and how far they've come -- pride is a word about growth. If a homeless guy on the street (lower status) or Bill Gates (don't know him personally) tell me they're proud of me it won't have a huge positive effect.