Philanthropy at the personal level is good. People need to interact with their city and know their neighbors and their issues. Mega donations at the national level are really just end-runs around our democracy. We need to figure it out as a society, not have a rich person come in and say 'I have money and this is how I want society to work'. Even if I agree with you, I don't really want any individual to have that much power over that many people. We need to constantly find ways as a society of encouraging individual voices and reducing the power of money as a voice.