Leibniz on Scotus and Aquinas

The following quotation is from Leibniz's Theodicy.  It is a section in which Leibniz discusses the idea of equipoise in the will, the Buridan's ass scenario in which the ass is confronted by two equally enticing piles of hay on each side of the road and is unable to choose between them.  Eventually, the Molinist controversy comes up, the immediate context of what follows.

Leibniz, Theodicy, tr. Huggard, p 324.

330. If the Scotists and the Molinists appear to favour vague indifference (appear, I say, for I doubt whether they do so in reality, once they have learnt to know it), the Thomists and the disciples of Augustine are for predetermination. For one must have either the one or the other. Thomas Aquinas is a writer who is accustomed to reason on sound principles, and the subtle Scotus, seeking to contradict him, often obscures matters instead of throwing light upon them. The Thomists as a general rule follow their master, and do not admit that the soul makes its resolve without the existence of some predetermination which contributes thereto. But the predetermination of the new Thomists is not perhaps exactly that which one needs. Durand de Saint-Pourcain, who often enough formed a party of his own, and who opposed the idea of the special co-operation of God, was nevertheless in favour of a certain predetermination. He believed that God saw in the state of the soul, and of its surroundings, the reason for his determinations.

331. The ancient Stoics were in that almost of the same opinion as the Thomists. They were at the same time in favour of determination and against necessity, although they have been accused of attaching necessity to everything. Ciecero says in his book De Fato that Democritus, Heraclitus, Empedocles and Aristotle believed that fate implied necessity; that others were opposed to that (he means perhaps Epicurus and the Academicians); and that Chrysippus sought a middle course. I think that Cicero is mistaken as regards Aristotle, who fully recognized contingency and freedom, and went even too far, saying (inadvertently, as I think) that propositions on contingent futurities had no determinate truth; on which point he was justifiably abandoned by most of the Schoolmen. Even Cleanthes, the teacher of Chrysippus, although he upheld the determinate truth of future events, denied their necessity. Had the Schoolmen, so fully convinced of this determination of contingent futurities (as were for instance the Fathers of Coimbra, authors of a famous Course of Philosophy), seen the connexion between things in the form wherein the System of General Harmony proclaims it, they would have judged that one cannot admit preliminary certainty, or determination of futurition, without admitting a predetermination of the thing in its causes and in its reasons.