Episcopius on the threefold knowledge, approving the distinction as useful for teaching
First, Simon Episcopius reports with approval the threefold distinction of knowledge in God that has been standard since Molina. 'It should be noted,' he says, 'that a threefold knowledge is usually ascribed to God.
One is necessary and practical and is called the knowledge of simple intelligence. By its nature it comes before every act of the free will, and by it God understands himself and everything else that is possible.
The second is free and is called the knowledge of vision. It comes after the act of the free will, and by it God knows everything he has decreed to do or permit, in the same order in which he decreed to do it or permit it to happen.
The third is middle knowledge, by which God knows what men or angels would do in their freedom under a condition, if they were placed in these or those circumstances, in this or that state or order.
Whether this distinction of divine knowledge is correctly drawn we do not examine. That it can be drawn usefully and for the sake of teaching we do not doubt at all.' Theological Institutions, book 4, chapter 19, On the order and manner of divine knowledge.
Latin
XXIII. Et primo quidem solennem a temporibus Molinae distinctionem triplicis in Deo scientiae, ut commodam refert Simon Episcopius. Observandum venit, inquit, triplicem Deo scientiam tribui solere. Unam, quae necessaria est, & practica, atq; simplicis intelligentiae dicitur, quae ex natura sua omni voluntatis liberae actu prior est, qua Deus seipsum & alia omnia possibilia intelligit. Alteram liberam, quae Visionis dicitur, & actu Voluntatis liberae posterior est, qua Deus omnia, quae facere, aut permittere decrevit eodem ordine novit quo ea decrevit facere, aut permittere ut fiant. Tertiam Mediam, qua Deus novit quid homines, aut Angeli pro sua libertate facturi essent, sub conditione, si cum his aut illis circumstantiis, in hoc vel in illo statu, aut ordine constituerentur. An haec divinae scientiae distinctio recte fiat, nos non expendimus. Quin ea commode & doctrinae gratia fieri possit, neutiquam dubitamus. Institutionum Theologicarum libro quarto, capite 19. De ordine & modo scientiae divinae.