Ockhamist Modernity

Suppose you’re walking to church to worship God. Along the way, your motive changes from piety to vainglory. You continue walking to church, but now you’re walking to church to be seen by others to be walking to church.

What happened to the action of walking to church when your will changed?

Thomas Osborne’s dense Human Act in Thomas Aquinas, John Duns Scotus & William of Ockham shows that different medieval accounts of action gave different answers to that question. For Thomas, “the walking to church with a good intention has as an exterior act the exercise of the powers of local movement used in walking, but merely insofar as these powers are moved by the interior act of willing a good end. Once the interior act of walking changes, there is a new exterior act even though the physical act of walking remains exactly the same” (188). The walking is “one according to the species of nature” but the change in motive produces “two exterior acts” (177).

Ockham thinks about this differently: “there is only one exterior act of walking and the two interior acts. He makes no distinction between the exterior act and the act according to the species of nature. Consequently, in such a case the numerically identical exterior act of walking is first good and then bad.” For Ockham, “the interior act carries all the moral weight” (177-8). Exterior acts have no moral worth. Nothing is good or bad but the willing makes it so.

A slight, almost imperceptible change, we might think, but Osborne sees in this shift in accounts of human action the stirrings of a new epoch. Ockham “severs the exterior or commanded act from the act of the will. Ockham’s focus is almost entirely on interior will acts,” and this “foreshadows some elements in modern moral philosophy” (xxv).