The Enlightenment idea that reason creates fixed moral rules that specify "the right thing to do" is mistaken, according to Johnson, because it misses the ways in which human conceptual systems are grounded in bodily experience, and it ignores the expansive and constructive nature of our best moral thinking. Since new findings in cognitive science explain reasoning in terms of prototypes, frame semantics, metaphor, and basic-level experience, Johnson contends that we must revise our views of ethics and adopt an alternative conception of moral reflection - one that is thoroughly imaginative.