Too much contemporary bioethical discourse is weak on science, lazily citing and adopting science fiction scenarios rather than science facts in the framing of analyses and policies. We challenge bioethicists to take more seriously the role of providing informed insight into and oversight over contemporary science and its implications and applications. Bioethicists must work harder to understand the fast-changing truths and limits of basic science, and they must incorporate only appropriate and authentic science into their discourse, just as they did (...) in the past when addressing the quandaries of clinical medicine. The field of bioethics is not so old and entrenched that its future is assured. Bioethicists must make themselves useful to society in order to deserve and retain the public's trust. They can best do this by ensuring that decision making and public policy are grounded in facts, not fictions and fantasies. (shrink)