For Bonaventure, then, light is a substantial form, but only the partial perfection of any given physical substance, whether celestial or terrestrial.
From this viewpoint, according to which the passive intellect has to be considered a substantial form, it is evident that it has a beginning in time, but certainly not an end, and that, like any other material substantial form, it is multiplied according to the multiplication of bodies (In Metaph., book XII, tr. 1, chap. 3, fol. 427ra b).
Considered as a substantial form of a material body, the soul exists in a living being as the substantial form of an animal.
To form a substance, or something that can exist by itself, prime matter must be "informed" by a substantial form (a form that renders something into a substance).
He outlined a number of reasons why they were jointly opposed to describing the human mind as a substantial form.
If a thing is not unified by a substantial form, then that thing has a lesser kind of unity.
Since it is an essence, a substantial form is what is denoted by the definiens of a definition.
Most fundamental among his many arguments against them is his conviction that a substantial form confers substantial being upon a composite substance.
In substantial generation or destruction, a substantial form is gained or lost; in mere accidental change, the form gained or lost is itself accidental.
He asserts that the substantial nature of the physical world is the unknown structure of atomic parts, not a substantial form which reflects our usual concepts.
