Apologeticae sive Theologiae Fundamentalis, Tomus I: Demonstratio Christiana

Both the historical truth and the philosophical truth of prophecy are knowable. As regards the historical truth, it is evident. A prophecy is historically true if it is established that a certain and determinate prediction of a future event was made and fulfilled. But this can be established in the same way in which the truth of any historical testimony and fact is established.

We know the philosophical truth of prophecy if it is established that the prediction, to which the event corresponded, is to be attributed neither to blind chance, nor to human conjecture, nor to diabolical knowledge. For if these three things are established, the cause of the prophecy is either God alone or at least a good angel. But for the most part it is established that the fulfilled prediction is not to be attributed:

Blind chance (Zufall, hasard). It can indeed happen that someone quite rashly predicts an event to which the outcome corresponds by chance, as when someone declares at his own pleasure: In ten years a great war will come, and this actually comes to pass. Nevertheless, a rash prediction is certainly excluded from being fulfilled by chance, if the predicted thing cannot be brought about by natural means (e. g. the prediction of a virginal birth or of the resurrection of a dead man), or if many things are predicted, or one thing indeed, but with diverse and minute circumstances (e. g. the messianic prophecies of the Old Testament). And the loftier the things, and the more numerous and more determinate the things that are predicted, the less can they be affirmed rashly and be fulfilled by chance, since chance is not constant.¹

Human conjecture. By conjectural knowledge (Vermutung, conjecture) man can indeed predict the effects of the physical world which follow necessarily from known causes, but by no means those events whose causes are wholly and entirely hidden. Likewise, by psychological experience we can conjecture by probable judgment certain future actions of men; but in a certain and determinate way we cannot predict what a man or men will freely do after a long time. Finally, the free decrees of God wholly escape human conjecture.

Diabolical knowledge. Demons indeed excel in reason and hence also in the most penetrating conjectural knowledge. Therefore they can foretell many physical effects that are inaccessible to us, and can presume many human actions with some probability. Nevertheless, not only the free decrees of God, but also the altogether free actions of men are inaccessible to them. For those objects are present neither in themselves nor in their causes, and therefore they cannot affect and determine any created intellect. But even in predicting the events of physical nature the demons are limited by divine providence, which does not permit men who use right reason to be led into error by evil spirits. For the rest, diabolical prophecies are distinguished from divine prophecies by the same criteria as diabolical miracles.²