Abstract

Conscience is the psychological faculty by which we aware of and respond to the moral character of our own actions. It is most commonly thought of as the source of pains we suffer as a result of doing what we believe is wrong --- the pains of guilt, or “pangs of conscience.” It may also be seen, more controversially, as the source of our knowledge of what is right and wrong, or as a motive for moral conduct. Thus a person who is motivated to act on principle is said to act “conscientiously.” These terms come from the Latin “conscientia,” a direct translation of the Greek “syneidesis.” This ranges in meaning from being aware of something to “knowing something in common with” someone. Knowing something in common with someone can mean sharing his secret, and this puts you in a position to serve as a witness against him. Thus the term came to have a judicial use, to describe one who could bear witness. In certain contexts, “syneidesis” came to mean a state of knowing in common with oneself, and so of bearing witness against oneself. Although these terms appear in Stoic and Epicurean works, conscience did not receive extensive philosophical treatment until the Medieval period, when treatises on conscience became standard. Medieval philosophers distinguished two aspects of conscience, “conscientia” and “synderesis.” Roughly, “synderesis” refers to the ineradicable and infallible basis of conscience in human nature, while “conscientia” refers to the more particular judgments we make about our actions. There are various ways of specifying the two ideas further. In Thomas Aquinas’s account, which became standard, synderesis grasps the basic moral principles which are the first premises of practical reasoning, while conscientia is the conclusion, the act of judging that one ought to perform a particular action.