a. Opinion of Henry of Ghent

27. As to the first matter, one assertion is [Henry of Ghent, Quodlibet 11 q.8] that “the first root of pain is an alteration in a fitting natural disposition that offends and corrupts it; the second and proximate root of pain is apprehension of this alteration.” The second root is not sufficient without the first, since otherwise the blessed could feel pain after the resurrection; for if one of the blessed were in fire he would apprehend the supreme heat perfectly but would not be harmed by it, and so, if mere apprehension without an alteration first were sufficient, someone blessed could be in pain while in a fire that was afflicting him.

28. But a distinction is made about apprehension, that apprehension is one thing and perception another; for sense apprehension has the sensible thing itself for object (as the apprehension of sight has color for object and the apprehension of hearing has sound for object), but the perception annexed to apprehension has an agreeable or harmful sense condition for object. This perception of what is agreeable or harmful has the power to move us to the experiencing of it that the thing itself has, as is plain from De Motu Animalium 7.701b16-32, that “phantasms sometimes, like things, move us to being warmed and cooled, and a small change in the heart causes a big one in the body; for just as a small change in the ship’s wheel causes a big change in the prow, so these sense intentions, possessing the power of the object, can move us to passions in the soul, namely pain; and they also accompany the body’s changes in its natural undergoings of hot and cold.”

29. In this way, then, apprehension is said to be only a cause sine qua non, as being the second root of pain; but perception, as the first root, is cause as to why there is pain. Because there is in a sense-intention of something agreeable and harmful the idea of being able to be moved to some passion in the soul (as being the object that the intention concerns), so the idea of moving power exists also in perception as to causing in the body the real undergoing that the perception in the soul accompanies.