Doing good for the world: Sam was consistently vegan in the time I lived with him, because he wanted to reduce farm animals' suffering. He was happy to discuss this (but not pushy, unlike stereotypical vegans), and by 2014 had converted about half of ET to vegetarianism or veganism. I did not become vegetarian or vegan, but I respected his efforts. Sam also took action on causes other than reducing animal suffering: he ran an event in which he gave MIT students $1 to donate to one of three charities (the Against Malaria Foundation, the Make-A-Wish Foundation, and a third I don't remember) with descriptions of what they could accomplish with how much money, hoping to get MIT students to think about effectively doing good for the world.
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