 Arnauld’s point is not that the actions of the prince and the king are causally determined by psychological states antecedent to their volitions. In both cases he says that the action is free because the person could have willed not to perform the action, or again, because the person’s will was a potestas ad opposita. Arnauld’s point is that our certainty that the prince and the king will act in the ways described does not lessen our certainty that they will act freely. The same, he says, is true of our certainty that a meritorious act will be carried out as a result of efficacious grace, that is, as a result of God’s merciful will moving a person to that act. Arnauld claims that our certainty about the freedom of the act produced by efficacious grace, like our certainty about the freedom of the actions of the prince and the king, is well grounded because in all of these cases, the person had the power to refrain from the act in question; in all of these cases, the person’s will is a facultas ad  opposita.[43]