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**Lecture 17**   # Trade and/or aid  Start by revisiting global egalitarianism from last lecture:  * global difference principle  * global equality of opportunity  * individualism versus culture  Mutual benefit motivates trade  * selfish  * trading parties well-informed about their own utility  Altruism motivates, to some extent, aid  * warm glow from giving  * donor not necessarily well-informed about recipient utility