Of God and His Creatures

By way of illustrating the importance of physical science to the theologian, I note two propositions of St Thomas in the fourth argument, here omitted:

(a) "No corporeal thing acts otherwise than through being in motion." So Aristotle, Physics, VIII, v.

(b) "It is impossible for the motion of anything to continue, when the motor action of the moving cause ceases to be."

The first proposition has not been reconciled with the laws of gravitation and of electric and magnetic attraction: the second is a denial of the inertia of matter. St Thomas took them both from Aristotle.

Of God and His Creatures: 3.65