Through this it becomes evident how much fantasy and error slip into discussions of this kind. This, however, is only after they have first agreed to label both the subject and the attribute as each other’s cause; otherwise such terminology is repugnant to sound instinct. For the subject—in our example, the silver coin—is merely the locus for this accident, just as every body is the locus for its own accidents. Hence anyone who claims that this particular form is not an accident like all other accidents is mistaken, and the same mistake is made by those who treat the attribute as a cause.

Had they said instead that the two are causes of the composite, the correct account would be that the craftsman is the one who effects that composition, for it is he who fashions the silver into a coin or a ring. As for making one of the two the cause of the other, all it really means is that an attribute cannot exist without a subject, and that the subject, precisely inasmuch as it is a subject, cannot exist without an attribute. This rule applies to every pair of attributes and subjects that accompanies every substance together with its accident.

When, moreover, they draw a distinction between substance and accident on the one side and matter and form on the other—as they in fact do—they define substance as the locus that can exist without what inheres in it, calling it the “substratum,” and they define matter as the locus that cannot dispense with what inheres in it. This distinction is unfounded. If by the independence of the locus they mean that it can exist stripped of the accident, that would also be true of the attribute itself; and if they mean that it is not independent because, considered as a composite, it is constituted by forms, that is the case with every accident.

The same reasoning holds for those forms that are natural accidents, such as the heat in fire and the coldness in water. When they say that heat is the form of fire, the “form” here is an accident inhering in a body, for heat inheres in the hot object and coldness inheres in the cold one.

As for those forms they regard as substances—when, for example, they say that the very body that subsists of itself is a form inhering in matter—even here the matter is not a self-subsisting substance. Rather, when they claim that connection and separation befall a body, and that the locus of connection and separation is other than the connected and the separated, then upon closer examination this too is