World’s third richest guy proposes higher taxes… for other people

I expect better logic form a professor at Harvard. It's a classic example of attacking a person's character rather than the position.

Using Greenspun's logic overweight people should have no publicly stated opinion regarding world hunger since they don't donate all excess food they have to hungry people.

A person's hypocrisy is not a valid retort to a position they have. Great, Buffet is a hypocrite. But is he right?