 One might take these passages to suggest that the freedom necessary and sufficient for merit and demerit is compatible with determination of the will by psychological causes. But this misses Arnauld’s point, and is an unlikely interpretation. To begin with, Arnauld surely realized that it was not impossible for the lascivious prince or the cruel king act otherwise than in the way described; people do sometimes act out of character. Furthermore, Arnauld seems to think of infallibility, like its cousin, certainty, as a matter of degree. This is indicated by the phrase, “However infallible be the determination by which the will is determined with the attention of reason …” The certainty that the cruel king and the lascivious prince would act in the ways indicated could have been very high and yet they could have acted otherwise.