Philosophy Phridays – Medieval Theories of Conscience

Philosophy Phridays is a series where each Friday, I go to the Stanford Encyclopedia of Philosophy, click on “random entry,” and then write about whatever comes up. This week’s random entry is Medieval Theories of Conscience.

When most people think of conscience, they think of that little voice in their heads telling them right from wrong. Or they think of Jiminy Cricket in Pinocchio. The idea of conscience has been around for a long time, but it has changed throughout the years. This article discusses conscience as described by Bonaventure, Aquinas, Duns Scotus, and William of Ockham. At the time, they all dealt with conscience in relation to synderesis. Synderesis is basically an innate moral consciousness (I hate using the word conscious in a piece about conscience. They’re just too similar.).

Bonaventure says that conscience is part of the rational part of people and that synderesis is part of the affective part (feelings). Conscience is then divided into two parts. The first knows general principles, like “obey God,” and is unerring. The second part applies those principles to specific situations. While the first part is unerring, the second can make mistakes, either mistakes of reasoning or mistakes of apprehension. Bonaventure considers synderesis to be a desire to do good. In that sense, it acts like the spark that gets conscience going.

Aquinas defines conscience as the, “application of knowledge to activity.” He says that the relevant knowledge comes from synderesis. Basically, synderesis give a person general principles, like “do good,” and the conscience applies that general principle to specific situations. Aquinas says that failure to follow the general principles comes from passion. A passionate desire to do something makes us see the action as the wrong type of activity and apply the wrong general principle to it.

Scotus sees conscience as related to the virtues. As it appears in the article, “one must perform appropriate virtuous actions to develop the habit of the virtue and to know the relevant right dictates.” Unfortunately, this is circular. You have to perform the virtues to learn the virtues, but you have to learn the virtues to perform the virtues. He uses conscience as the way into the circle. For him, the conscience determines what is to be done in a given circumstance. Performance of the conscience actions can be the basis for learning the virtues and allows the circle to get started.

Ockham had similar views to Scotus. The main difference is that he believed that there was more nuance that Scotus admitted. There are degrees of virtues that must be accounted for.

So, why is this important? It’s not, really. It’s interesting from a history of ideas perspective. And it can be interesting to contrast the medieval, rational conscience with the modern notion that conscience is a faculty. But that’s about it. I think I’ve mentioned before that medieval philosophy isn’t my favorite. It’s just what randomly came up today.

Langston, Douglas, “Medieval Theories of Conscience”, The Stanford Encyclopedia of Philosophy (Fall 2015 Edition), Edward N. Zalta (ed.), URL = <>.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.