Mr. Greenburg falls, as many do, for the too simplistic meaning of Rand's "rational self interest". Thinking on a deeper level it can be in my rational self interest to be an honorable, decent, caring and sharing person. Being selfish and greedy will on work in a society for a short time before "what goes around comes around. Under her philosophy I can and should pursue my interests and what makes me happy, not based on what other people or the state want me to do. So if I chose to be charitable, kind and helpful, then I am right to do it for my own happiness.