equivalent to the proposition "I disapprove of theft". Having argued that his theory of ethics is noncognitive and not subjective, he accepts that his position and subjectivism are equally confronted by G. E. Moore's argument that ethical disputes are clearly genuine disputes and not just expressions of contrary feelings. Ayer's defense is that all ethical disputes are about facts regarding the proper application of a value system to a specific case, not about the value systems themselves, because any dispute about values can only be resolved by judging that one value system is superior to another, and this judgment itself presupposes a shared value system. If Moore is wrong in saying that there are actual disagreements of value, we are left with the claim that there are actual disagreements of fact, and Ayer accepts this without hesitation: C. L. Stevenson Stevenson's work has been seen both as an elaboration upon Ayer's views and as a representation of one of "two broad types of ethical emotivism." An analytic philosopher, Stevenson suggested in his 1937 essay "The Emotive Meaning of Ethical Terms" that any ethical theory should explain three things: that intelligent disagreement can occur over moral questions, that moral terms like good are "magnetic" in encouraging action, and that the scientific method is insufficient for verifying moral claims. Stevenson's own theory was fully developed in his 1944 book Ethics and Language. In it, he agrees with Ayer that ethical sentences express the speaker's feelings, but he adds that they also have an imperative component intended to change the listener's feelings and that this component is of greater importance. Where Ayer spoke of values, or fundamental psychological inclinations, Stevenson speaks of attitudes, and where Ayer spoke of disagreement of fact, or rational disputes over the application of certain values to a particular case, Stevenson speaks of differences in belief; the concepts are the same. Terminology aside, Stevenson interprets ethical statements according to two patterns of analysis. First pattern analysis Under his first pattern of analysis an ethical statement has two parts: a declaration of the speaker's attitude and an imperative to mirror it, so "'This is good' means I approve of this; do so as well." The first half of the sentence is a proposition, but the imperative half is not, so Stevenson's translation of an ethical sentence remains a noncognitive one. Imperatives cannot be proved, but they can still be supported