 Ayer, Alfred Jules |  compositionality |  fictionalism |  Hume, David: moral philosophy |  metaethics |  Moore, George Edward |  Moore, George Edward: moral philosophy |  -->moral anti-realism--> |  moral motivation |  moral non-naturalism |  -->moral realism--> |  moral skepticism |  naturalism: moral |  realism |  relativism |  Stevenson, Charles Leslie |  supervenience |  truth: deflationation about 