 For an act to be altruistically motivated is for the benefactor—not the beneficiary—to have a certain attitude towards it. A child who acquires from a tennis instructor the skills of a good athlete and a love of the game may simply think of tennis as great fun—not as something that benefits him or as a constituent of his life going well. The child does not need to practice his skills because he believes that doing so is good for him: that is not a necessary condition of his being the beneficiary of an altruistic act. Similarly, someone might deny that physical suffering counts as something that is bad for him. (He should deny this, according to the Stoics.) But on any plausible theory of well-being, he is wrong about that; someone who aims to diminish the pain of another individual, out of a concern for that individual’s well-being, is acting altruistically. 