 What is the ‘good-maker’, according to objective list theorists? This depends on the theory. One, influenced by Aristotle and recently developed by Thomas Hurka (1993; see Bradford 2017), is perfectionism, according to which what makes things constituents of well-being is their perfecting human nature. (On the history of modern perfectionism, see Brink 2019.) If it is part of human nature to acquire knowledge, for example, then a perfectionist should claim that knowledge is a constituent of well-being. But there is nothing to prevent an objective list theorist’s claiming that all that the items on her list have in common is that each, in its own way, advances well-being.