It is sometimes said that there is no progress in philosophy but, although philosophical progress differs in many respects from that in other disciplines, the medieval discussion of conscience shows that the notion is not entirely inapplicable to philosophy, too. For, on the one hand, there is a clearly discernible development in the thought of the three authors whose work on conscience has been studied here while, on the other, there are aspects of the topic to which we should be sensitive today to which they were blind. At this stage, it is worth drawing up a balance-sheet itemising the credits and debits which may be assigned to them.

The first item to be recorded is the surprising lack of attention which they pay, when we consider that they were professional theologians as well as philosophers, to biblical material on conscience. Of the texts which a modern biblical scholar would discuss were he writing on this topic (cf. e.g. Davies, 1962; Pierce, 1953), very few are cited by Philip, Bonaventure or Aquinas and even fewer play more than an incidental role in their arguments. Whether we assign this to the credit or to the debit side of the account will depend upon our point of view, but it has at least the result that a great deal of their discussion is accessible to philosophers who do not share their theological beliefs.

I have argued that the distinction between synderesis and conscientia, as expounded by Philip and developed by Aquinas, belongs to the credit column.