In contemporary reflection on the foundations of ethics, natural law theory continues to play an important role despite opposing objections. In an approach to moral issues, paying attention to cultural differences and historical changes is appropriate, but it is also important to take a stance on the existence of basic moral common sense shared by diverse times, places, and cultures. As defined by medieval thinkers, synderesis represents the core of this moral common sense that cannot err, incline towards error, or (...) be corrupted. (shrink)