It is said that one should put others before oneself, but isn't this impossible? Consider two people, Mr A and Miss B. If A succeeds in putting B before himself, B can't put A before herself. Hasn't B been forced into being selfcentred by A?

There can be a paradox here: imagine Mr. A vows he will not go through a door unless Miss B goes first, and Miss B vows she will not go through the door unless Mr. B goes first. Sadly, they may be in a fix, unless the two of them fall prey to optical illusions or somehow wrongly come to believe that the other has slipped through the door first and the way is clear for them. But in your case of A and B altruism, I am not sure the problem is arresting: imagine that A gives primacy to B and so goes and prepares lunch for her, whereas B gives primacy to A and prepares lunch for him. In this case, perhaps they both enjoy lunch (especially if they both believe it would be showing respect to the other to eat together --Mr. A might enjoy his lunch out of consideration for Miss B, while Miss. B would enjoy her lunch for the sake of Mr. A).

I wonder whether your case might raise a question about the alternatives you have set up. You seem to give us two choices: either put another person first or be self-centered. But maybe you can treat yourself and others without thinking that any one of us is "number one" but we are each one among others? And when I do "look out for myself," am I (ipso facto) being self-centered? Maybe I am looking out for myself, so others do not need to look out for me. Perhaps I do not want to be a burden on others. As a colleague likes to say, one reason for learning how to brush your teeth (and actually doing so) is so that others do not have to brush your teeth for you.

Your case of when a kind of altruism might lead to being self-centered brings to mind that philosophers have spent time working on paradoxes of when following some principle (might) lead to its denial. For example, some utilitarians have wondered what to do if there were good reasons to believe that people would promote the greatest utility (or happiness) if they denied the truth of utilitarianism. Or imagine that a person truly believes God exists and should be obeyed and yet has a religious experience in which God appears to command that the believer deny that God exists.

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