 Other projects involve using evolutionary biology to try to undermine traditional  moral realism—the  view that moral judgments can be true (accurately representing moral facts) when construed literally, that their truth does not depend on our evaluative attitudes, and that we can know at least some of these truths. Such arguments are taken to support moral skepticism (according to which we cannot possess moral knowledge) or  moral antirealism  (for example, views that construe moral truths as functions of our evaluative attitudes, or expressivist views according to which moral judgments function to express attitudes, acceptance of norms, etc., rather than to represent moral facts, or error theoretic views according to which all moral judgments are false).