Practical Reason

Aquinas on Conscience

In this course Dr Daniel De Haan (University of Oxford) explores St. Thomas Aquinas’ doctrine of conscience. In the first module we introduce Aquinas’ account of practical reason, and its relevance to the doctrine of conscience. After that, we explore Aquinas’ views on the judgment of conscience in the Summa Theologica. In the third module, we look at two further features of practical reason: synderesis and prudence, before moving on to Aquinas’ take on moral responsibility. Finally, in the fifth module, we look at the demands of conscience in everyday life, and Aquinas’ challenge to ‘moral dilemmas’.

Practical Reason

In this module, we introduce Aquinas’ account of practical reason, focusing in particular on (i) reason as an operation of the power of intellect (ii) two powers of intellect: intellectus agens, and intellectus possibilis (iii) how we use reason to deploy the intellect, and (iv) the relationship between practical reasoning and human action.