This chapter discusses the fact-value problem in metaethics and different theories that have attempted to address it. It introduces Hume's view that one cannot derive ought from is, Moore's naturalistic fallacy that you cannot define goodness in natural terms, and Ayer's emotivism which holds that moral statements express attitudes rather than having truth values. It also covers prescriptivism proposed by Hare which sees moral judgments as having both descriptive and prescriptive elements.

4. The Fallacy of Deriving Ought from Is Hume: In every system of morality which I have hitherto met with, I have always remarked, that the author proceeds for some time in the ordinary way of reasoning, and establishes the being of a God, or makes observations concerning human affairs; when of a sudden I am surprised to find, that instead of the usual copulations of propositions, is, and is not, I meet with no proposition that is not connected with an ought, or an ought not.

9. Verification Principle A statement is meaningful if and only if it is either tautological or empirically verifiable

16. Criticisms of Prescriptivism 1. It is too broad and allows for conduct that we typically deem immoral 2. It permits trivial judgments to count as moral ones 3. It allows the moral substance in life to slip away from ethical theory 4. There are no constraints on altering one's principles

17. Naturalism Links moral terms with some kind of natural property. Natural in that they are found in the natural world, specifically the natural realms of human psychology and human society

18. Naturalism and the Open-Ended Argument Moore's theory regards the idea of goodness as though it were a thing, the fallacy of hypostatization It's a category mistake to treat a functional term as though it were a thing