But it must be noted that if the stronger power goes so far as to transform the contrary inclination into its own inclination there will be no longer repugnance or violence: thus if a stronger agent, by its action on a heavy body, deprives it of its downward tendency, its consequent upward tendency is not violent but natural to it.
Accordingly if some greater power prevail so far as to take away from the will or the sensitive appetite, their respective inclinations, pain or sorrow will not result therefrom; such is the result only when the contrary inclination of the appetite remains. And hence Augustine says (De Nat. Boni xx) that sorrow is caused by the will "resisting a stronger power": for were it not to resist, but to yield by consenting, the result would be not sorrow but pleasure.
Reply Obj. 1: A greater power causes sorrow, as acting not potentially but actually, i.e. by causing the actual presence of the corruptive evil.
Reply Obj. 2: Nothing hinders a power which is not simply greater, from being greater in some respect: and accordingly it is able to inflict some harm. But if it be nowise stronger, it can do no harm at all: wherefore it cannot bring about that which causes sorrow.
Reply Obj. 3: External agents can be the causes of appetitive movements, in so far as they cause the presence of the object: and it is thus that a greater power is reckoned to be the cause of sorrow. ________________________
QUESTION 37
OF THE EFFECTS OF PAIN OR SORROW
(In Four Articles)
We must now consider the effects of pain or of sorrow: under which head there are four points of inquiry:
(1) Whether pain deprives one of the power to learn?
(2) Whether the effect of sorrow or pain is to burden the soul?