The Role of Negative Thinking in Charity

In order to harm, you must leave someone worse off. You can't harm somebody by making them better off overall. I think the problem is that the world as a whole is very, very low in terms of what we give or what we regard as an acceptable amount to give to charity. How hard should I be on myself when I'm giving a substantial portion of my income to effective charities, but not to be as much as I really ought to be? That's kind of...