In this first episode of a two part installment, I look at the work of David Hume and his ideas that justify that famous quote of his “Reason is, and ought only to be the slave of the passions.” This quote has always troubled me. As politico-moral beings, many don't want to classify a horrific act as merely bad. There is also an urge to classify that horrific act as irrational. Does reason really tell us nothing about morality? Is reason just a way of determining efficient means to an end? Was Hitler evil and rational, or, just evil? What work can a concept of rationality do to condemn an evil act? In this episode, I look at the work of Peter Railton, a Hume scholar, who argues that people often interpret Hume's quote incorrectly. According to Railton, Hume believed that rationality does have a robust role to play in determining which acts are moral or immoral. Hume's point was rather that rationality in isolation could not tell us much about morality but working in conjunction with our sentiments, rationality could help determine for us which acts are moral or immoral.