31.8

Reply to Objection 2. Pleasure, in the emotions of the soul, is likened to natural repose in bodies: because its object is something suitable and connatural, so to speak. But sadness is like a violent repose; because its object is disagreeable to the animal appetite, just as the place of violent repose is disagreeable to the natural appetite. Now natural repose is contrary both to violent repose of the same body, and to the natural repose of another, as stated in Phys. v, 6. Wherefore pleasure is contrary to both to another pleasure and to sadness.