Whether charity is the form of the virtues?

Objections

Objection 1 : It would seem that charity is not the true form of the virtues. Because the form of a thing is either exemplar or essential. Now charity is not the exemplar form of the other virtues, since it would follow that the other virtues are of the same species as charity: nor is it the essential form of the other virtues, since then it would not be distinct from them. Therefore it is in no way the form of the virtues.
Objection 2 : Further, charity is compared to the other virtues as their root and foundation, according to Eph. 3:17: "Rooted and founded in charity." Now a root or foundation is not the form, but rather the matter of a thing, since it is the first part in the making. Therefore charity is not the form of the virtues.
Objection 3 : Further, formal, final, and efficient causes do not coincide with one another (Phys. ii, 7). Now charity is called the end and the mother of the virtues. Therefore it should not be called their form.