The View That All of Our Choices and Actions,even Those

The view that all of our choices and actions,even those that seem altruistic,are selfish,is the thesis of psychological egoism.
Write an essay explaining and criticizing this thesis,and defending the possibility of altruism.
Begin your essay with a story that apparently illustrates psychological egoism-either the Abraham Lincoln story or another story of your own-and then construct an argument for why the egoistic interpretation of this story isn't necessarily true.
Then discuss how psychological egoism differs from ethical egoism,and why ethical egoism isn't true.
You can use materials from chapter eight,but also your own ideas.