are nevertheless accidents. Now, an accident is that which the quiddity (1) can exist in external reality without—such as tallness and shortness, health and illness, the redness or yellowness of colour, and the like. Some accidents are inseparable from the individual but not from the species, like his very faculty of seeing; some are slow to disappear, such as youthfulness and pain; and some pass quickly, like the blush of embarrassment or the pallor of fear.
Given this, when he states in his proof that disparate things may agree in incidental matters—citing man and other animals sharing food and movement—we answer: nourishment pertains to animals, and voluntary movement is necessary to their quiddity; indeed, it is essential to them, for an animal is “a sensing, growing body that moves by will.” How, then, can movement be called an accident, let alone a separable accident? If he retorts, “By ‘accidental’ I mean whatever is contingent, whether inseparable or not,” the very basis of his division into “necessary” and “accidental” falls apart; for what is necessary already includes both the essential and the inseparable accidental, whereas he has not divided these qualities into essential and accidental, but into necessary and separable accident—yet, by the consensus of rational people, the properties in question are not separable accidents. This is our objection to what that polemicist has advanced.
Furthermore, what undermines his discourse and that of others is your statement that the species and the genus may coincide in a property that is either necessary or accidental (2). You may choose another path to invalidate this proof, namely, the path of counter-argument: what he adduces here regarding two beings of necessary existence he wishes to parallel in the distinction between necessary and possible existence, and between what is necessary in itself and what is necessary through another—yet there is no means of establishing such a claim. There is no doubt that being exists, and no doubt that existence is either necessary; we also observe things coming into existence after having been nonexistent, so they certainly cannot be necessary in themselves, for whatever is necessary