Proof of the Non-Existence of God in 6 Easy Steps?

0. There is no such thing as a purely selfless act.
1. Therefore all action is, at some level, “selfish”.
2. Therefore there are no good deeds or bad deeds, only action or inaction.
3. Therefore there is no morally right or wrong.
4. Therefore there cannot be a heaven or hell.
5. Ergo, God does not exist?