Several years ago, when Dr. Olson first published Arminian Theology and I noted his objection to the idea that Arminius held to middle knowledge1 (the idea that God knows what we would freely do under any circumstance), I wrote a brief post quoting Arminius’ use of middle knowledge. (link) At the time I thought it was a simple matter of pointing out the people that Arminius used the concept of middle knowledge. Surprisingly, this has not been the case; some Arminians are still reluctant to agree that Arminius held to middle knowledge. This, I think, is to their loss, since according to William Lane Craig, middle knowledge is one of the most fruitful theological concepts he has come across and according to Eef Dekker, Arminius introduced middle knowledge into protestant theology.
I recently went through Arminius’ response to Perkins again, which I really enjoyed. Below is a list of eleven quotes from just Arminius response to Perkins where he uses the concept of middle knowledge. Here are the quotes:
For He is the first cause, and the cause of causes, who, from the foreseen free act of rational creatures, takes occasion to make any decree, and to establish a certain order in events; which decree He would not have made, and which order He would not have established, if the free second causes had acted otherwise.
It can not be concluded from an event that God has willed something, but we may know either this fact, that He was unwilling to hinder an event which He foresaw would occur. -- Otherwise the distinction, which exists between the action and the permission of God, is destroyed.
yet the decree of God is not, therefore, dependent on the man, for He foresaw from eternity what would be in the future, and in ordaining, concerning the future, to that end, He freely arranged it according to His own choice, not compelled by any necessity as if He could not, in some other way, have secured glory to Himself from the sin of man.
God does not will this result [hardening], unless He also foreknows that future admonition will be useless through the wickedness, not through the infirmity, of those who are admonished, and unless He has already frequently invited them in vain to repentance, as in Isa. vi, 10, "Make the heart of this people fat, and make their ears heavy," &c.
But He knew that they would do this [i.e. Hezekiah and the Ninevites would repent if warned], being, indeed, assisted by grace and the divine aid, by which He had determined to co-operate with the external preaching; and so He determined to prolong the life of Hezekiah and to preserve the city of the Ninevites from destruction.
Your objection to this argument, namely, that, from it the conclusion is drawn that "such things are done, either through the ignorance or through the negligence of the Deity, is absurd; you can not defend it, even against yourself. For you have already made a distinction between "not to will" and "not to care that a thing should be done." Therefore, you can not deduce one from the other. How, also, can it be asserted that a thing is done without the knowledge of God, which is done by the permission of God, and by His will, the agent of that permission. But, it will hereafter appear, when we shall have explained, more largely, in reference to that permission, that what God permits, He does not permit without knowledge or care.
The passage in 1 Peter 3:17, is to be explained in a similar manner. "God wills that the pious should suffer evils," for their chastening and trial. He wills that they should suffer these evils from other men; but from men of what character? From those, who of their own wickedness and the instigation of Satan, already will to bring those evils upon them, which ill will God already foresaw, at the time when He predetermined that those evils should be inflicted upon the pious.
From this it is apparent that permission must be preceded by the prescience or the knowledge of the fact that both sufficient strength and an inclination to perform the act, exist in him, to whom the permission is granted. The mode of permission is the suspension of efficiency, which efficiency is also possible to the being, who permits, either according to right, or according to capability, or in both respects, and, when used, would restrain, or in fact prevent the act. We may, hence, define permission in general, thus; -- It is the act of the will by which the being, who permits, suspends any efficiency which is possible to him, which, being used, would restrain, or, in fact, prevent an act in him to whom the permission is granted, to the performance of which act the same person has an inclination and sufficient strength.
God acts, preventively, on the will by suasion, when He persuades the will by any argument, that it may not will to perform an act, to which it tends by its own inclination, and to effect which the creature has, or seems to himself to have, sufficient strength. By this, the will is acted upon preventively, not of necessity, indeed, but of certainty. But since God, in the infinity of His own wisdom, foresees that the mind of the rational creature will be persuaded by the presentation of that argument, and that, from this persuasion, a prevention of the act will result, He is under no necessity of using any other kind of prevention.
Yet it is certain, whatever that act may be, that it is efficacious for prevention, and will certainly prevent, which efficacy and certainty depends, not so much on the omnipotence of the divine action as, on the prescience of God, who knows what arguments, in any condition of things or at any time, will move the mind of man to that, to which God desires to incline him, whether on account of His mercy or of His justice.
Who has deserved that a blessing should be offered to him? Who has deserved that grace of any kind should be bestowed on him to the obtainment of that blessing? Do not all these things pertain to gratuitous divine favour? If so, is not God to be extolled, on account of them, with perpetual praises by those, who, having been made partakers of that grace, have received the blessing of God? Of what importance to this matter is it, whether he may have obtained the offered blessing by the aid of common or of peculiar grace, if the former, as well as the latter, has obtained the free assent of man, and it has been foreknown by God that it certainly would obtain it?
1 No one questions that Arminius occasionally but rarely said things that could be interpreted as Molinist. Witt is right that in general, however, the Dutch theologian rejected middle knowledge, especially as it might be used by God to predetermine decisions and actions of human persons. The logic of Arminius's account of free will steers away from determinism, but one uses of middle knowledge is to explain how the actual world is determined by God using knowledge of what free creatures would do in any given world, including the one God ultimately decided to create - this one. Arminius averred repeatedly that determined acts cannot be sinful." (Arminian Theology. 196)