Is Psychological Egoism True Why Or Why Not?

Is Psychological Egoism True Why Or Why Not? Sometimes people benefit from helping others (e.g. experience pleasure). Sometimes such benefit presupposes a desire for what generated it (e.g. food), not for the resulting benefit. So sometimes people desire things other than self-interest. Therefore: Psychological egoism is false. Why psychological egoism is true? Psychological egoism is