In moral theory the view that we are receptive to moral facts, and able to know them in a way analogous to that in which we know some other class of facts. Naturalism will compare moral knowledge to natural empirical ways of knowing things about the world, while rationalism may make the analogy with mathematical or logical knowledge. Intuitionism unfortunately leaves the comparison class obscure, as well as being notably silent about why we have any interest in the facts that it posits See also expressivism, quasi-realism.