In a forthcoming paper entitled Does the Purpose Theory of the Meaning of Life Entail an Irrational God, I defend the Purpose Theory (PT) of the meaning of human life. PT is the position that God’s telic creation of human beings is a necessary condition for human life to be objectively meaningful. My defense of PT suggests a new argument for Molinism. The argument is implicit throughout the paper, although it is somewhat more explicit in my response to the final objection to my defense of PT. The argument can be formally expressed as a reductio ad absurdum, which I have labeled below as the Practical Rationality Argument (PRA).
Assumption (A): PT
Assumption (B): Human life is objectively meaningful.
Assumption (C): Human beings have libertarian free will.
- God lacks middle knowledge. (Assumption for RAA)
- If God lacks middle knowledge, then God is practically irrational.
- Thus, God is practically irrational. (1, 2 MP)
- God is not practically irrational.
- Thus, God is practically irrational and God is not practically irrational. (3, 4 CONJ)
- Thus, God does not lack middle knowledge. (1-5, RAA)
- Thus, God possesses middle knowledge. (6, DN)
Support for (C)
(A) and (B) are relatively uncontroversial for Christian theists. However, (C) is debated among Christian philosophers and theologians. As such, it is fitting to provide a word of support for (C). Consider Tim Stratton’s Free-Thinking Argument (FTA).
- If humans do not possess libertarian freedom, then humans do not possess the ability to gain knowledge via the process of rationality.
- Humans do possess the ability to gain knowledge via the process of rationality.
- Therefore, humans possess libertarian freedom. 
Support for (2)
Practical rationality requires intending the necessary means to one’s intended end. In other words, if one intends an end which requires certain means, then one wills those means. Hence, if one does not will the means, rationality requires that he not pursue the end. It is practically irrational to pursue an end without the necessary means. Consider John Broome: “It is commonly recognized that rationality requires you to intend what you believe is a necessary means to an end that you intend.” R. Jay Wallace puts the point as follows: “Instrumental rationality, in its most basic form, instructs agents to take those means that are necessary in relation to their given ends. In the modern era, this form of rationality has widely been viewed as the single unproblematic requirement of practical reason.”
Moreover, practically irrational behavior can be reckless and can endanger the well-being of human persons. For example, if I intend to squat 400 pounds but lack and never intend the means to do so, such as exercising and eating appropriately and patiently increasing my leg strength over time, then I am practically irrational regarding my goal. My practically irrational effort to squat 400 pounds would likely bring harm to human persons, namely, myself and anyone who needs me to be healthy, such as my family, my students, and my employers.
Now, if God lacks MK, then logically prior to creation God intended an end (namely, a world with a sufficient number of libertarianly free humans who freely choose to know and love him forever) but lacked the means (MK) to plan out the accomplishment of this end. Such practically irrational behavior could lead to serious and everlasting harm to human persons. Suppose, for example, that in the actual world every libertarianly free human person freely chooses to reject God’s purpose. If God lacks MK, then logically prior to creating the actual world he was unable to know that this universal and free rejection would happen. In the logically prior state, God knew it could happen. But he needs MK to know that it would happen and to plan accordingly. Arguably, without MK, God’s decision to create is practically irrational and reckless, which is absurd.
One might be inclined to object to (2). Why think that MK is necessary for God to plan his telic creation of a world with libetarianly free human beings? To answer this objection, consider the possible explanations for how God planned the world logically prior to his decree to create: (i) MK; (ii) causal determinism (hard or soft); (iii) simple foreknowledge; (iv) an open theistic explanation. (ii) is ruled out, given (C). Regarding (iii), without MK, it is hard to explain how God has foreknowledge. Logically prior to creation, how could God foreknow the contingent free choices of creatures if he lacks MK? The creatures do not yet exist. Arguably, time does not yet exist, either. Thus, there are no human beings to foreknow and there is no time to serve as the temporal domain into which God can project his foreknowledge. Concerning open theism, how could God be certain to avoid creating a world in which all (or at least too many) libertarianly free human persons freely choose to reject his purpose? In the logically prior state, God knew such a world could be. But, as noted earlier, he needs MK to know which world, if any, would be that way and to plan accordingly. As Thomas Flint writes:
“For the Molinist God, thanks to middle knowledge, is not a risk taker. He never has to deal with acting in situations where he knows only what probably would result from his actions. Rather, he knows precisely how his free creatures would react to any action on his part. If he were to put Libby in situation A, she would freely do X; if he were to put her in situation B, she would do Y; and so on. God can then decide which situation to put her in (say, A or B) depending on which result (X or Y) can more readily be woven into a world that satisfies his creative intentions. God need not worry about things heading off in an unintended direction—about his being surprised by unexpected actions on the part of his creatures. With middle knowledge, he truly does know what he is about. By exercising his providential control through the free actions of his creatures, he (and we) are assured that the world that results will fully manifest his wisdom and love.”
Elsewhere, Flint writes: “The answer to these questions is evident: providence can be exercised, free knowledge can be present, only if God knows how his free creatures would freely act if placed in various different situations.” Flint continues: “Finally, middle knowledge makes it possible for the Molinist to explain just how it is that God’s good plan for his world can be achieved with certainty.” God’s MK enables him to guarantee the success of his plan for the world. In short, unless one is inclined to appeal to mystery, MK best explains how in the logically prior state God planned his creation of the world.
Support for (4)
God is the greatest conceivable being. Therefore, God possesses every perfection and has no imperfection. Practical rationality is a perfection. Practical irrationality is an imperfection. Hence, God is practically rational and not practically irrational in any way.
In this short essay, I have presented a new argument in support of Molinism. The argument can be summarized as follows. If God lacks middle knowledge, then God is practically irrational. But it is absurd to hold that God is practically irrational. Thus, God does not lack middle knowledge. Thus, God possesses middle knowledge.
 I am not aware that this argument has been published elsewhere.
 See Stratton’s Free Thinking Ministries website at https://freethinkingministries.com/ for more information on the FreeThinking Argument (FTA). To support the FTA, consider the phenomenological experience of free will. Arguably, we are directly aware of our libertarianly free choices. This awareness justifies the belief that we have libertarian free will.
 John Broome, “Rationality,” in A Companion to the Philosophy of Action, ed. Timothy
O’Connor and Constantine Sandis (Oxford: Wiley-Blackwell, 2010), 289.
 R. Jay Wallace, Practical Reason, Stanford Encyclopedia of Philosophy, ed. Edward N.
Zalta, accessible at https://plato.stanford.edu/entries/practical-reason/#InsStrRat.
 Thomas Flint, Molinism, Oxford Handbooks Online, accessible at http://www.oxfordhandbooks.com/view/10.1093/oxfordhb/9780199935314.001.0001/oxfordhb-9780199935314-e-29.
 Thomas Flint, “Two Accounts of Providence,” in Oxford Readings in Philosophical Theology, ed. Michael Rea (Oxford: Wiley-Blackwell, 2010), 22.
 Ibid., 27.
 I believe that an appeal to mystery is justified, but only after one has exhausted all explanatory resources.