Confucius

The ultimate life coach of ancient China who basically invented 'adulting.' Confucius was obsessed with proper behavior, respect for elders, and doing things the right way - basically your Asian grandparent's voice in philosophical form. He failed at politics (kept getting fired for being too moralistic), so he became a teacher instead, wandering around with his disciples. His teachings weren't written by him but by students who apparently memorized everything he said (imagine having THAT much faith in your teacher). His influence is so massive that for over 2,000 years, you couldn't get a government job in China without passing tests on HIS books. He turned 'be nice to your parents' into a civilization-shaping philosophy. That's legacy.