This is a three-pronged question: What is The FreeThinking Argument? What are the premises of the argument? And what reasons are there to believe that the premises are true?
Please lay out a defense of all of the argument’s steps.
Thank you for the question, Evan.
Before I explain and defend the FreeThinking Argument, it is vital to define a term that the argument hinges upon: Libertarian Freedom (libertarian free will/libertarianism).
Technical Definition of Libertarianism:
Libertarianism is the view that (1) free will is incompatible with determinism, and (2) that some of our actions are free.
Some maintain that an agent is free in a libertarian sense, only if they possess the freedom to think or act otherwise. It seems, however, that if an agent is ever uncaused — and is simply the source of his or her thought or action (even if the agent cannot think or act otherwise for some weird reason) — then they still are free in a libertarian sense.
We can distinguish between the Principle of Alternative Possibilities (PAP)/the “ability to do otherwise” version of libertarian freedom and the source version. Both appear true. But, while the PAP is sufficient for libertarian free will (LFW), I do not claim that it is always necessary. The source version of LFW, on the other hand, is necessary.
Be that as it may, I typically defend a specific definition of libertarian freedom that seems to entail both versions:
Libertarian Freedom: The ability to choose between or among a range of alternative options each of which is compatible with one’s nature.
With the concept of libertarian freedom clarified, dig into the FreeThinking Argument. Begin with the first version of the argument I crafted and then we will expand it to the FreeThinking Argument Against Naturalism.
The “Core” of the FreeThinking Argument is not against naturalism. It is simply for libertarian freedom. It says nothing about God, Christianity, Calvinism, Molinism, Arminianism, Open Theism, atheism, naturalism, or any other “ism.” Consider the “Core”:
- If humans are not free (in the libertarian sense), they cannot either rationally infer or rationally affirm claims of knowledge.
- Humans can rationally infer and rationally affirm claims of knowledge.
- Therefore, humans are free (in the libertarian sense).
I then added two additional premises which simultaneously added two deductive conclusions and one abductive conclusion (the wording of the “core” below is changed but equivalent to the syllogism above):
- If naturalism is true, the immaterial human soul does not exist.
- If the soul does not exist, libertarian freedom does not exist.
- If libertarian freedom does not exist, then it is impossible to either rationally infer or rationally affirm knowledge claims.
- It is possible to rationally infer and rationally affirm knowledge claims.
- Therefore, libertarian freedom exists.
- Therefore, the soul exists.
- Therefore, naturalism is false.
- The best explanation for the existence of libertarian freedom and the soul is [the biblical view of] God.
I typically and briefly defend each premise in the following manner:
Basically, premise (1) is synonymous with “if naturalism is true, nature is all that exists.” That is straightforward. Premise (2) is tantamount to “if all that exists is nature, then all that exists (including everything about humanity) is causally determined via the laws of nature, the initial conditions of the big bang, quantum mechanics, and things outside of human control.”
Premise (3) is equivalent with “if all things are causally determined, then that includes all thoughts and beliefs.”
If our thoughts and beliefs are forced upon us, and we could not have chosen better thoughts and beliefs, then we are simply left assuming that our determined thoughts and beliefs are good (let alone that our beliefs are true). Therefore, we could never rationally affirm that our beliefs really are the inference to the best explanation – we could only assume it [and that assumption would not be up to us either, it is something completely out of one’s control].
Regarding this issue, Craig and Moreland (2017:66) write:
“If one is to have justified beliefs…then one must be free to obey or disobey epistemic rules. Otherwise, one could not be held responsible for his intellectual behavior.”
Here is the significant problem for the atheistic naturalist: it logically follows that if naturalism is true, then atheists — or anyone else for that matter — cannot possess justification for their beliefs (which is typically minimally required for knowledge). One can happen to have true beliefs; however, if they do not possess justification for a specific belief, their belief does not qualify as a knowledge claim. With this in mind, if one cannot freely infer the best explanation, then one has no justification that their belief really IS the best explanation. Without justification for a belief, any claim of knowledge regarding said belief goes down the drain. All we are left with is question-begging assumptions (a logical fallacy).
Obviously humans possess the ability to rationally affirm claims of knowledge. To argue against this would affirm it as one would have to offer claims of knowledge to the contrary. Moreover, if one rejects the ability to rationally affirm knowledge claims, why should anyone listen to them? Therefore, libertarian freedom and the soul (or some immaterial aspect of humanity) exists, and therefore, naturalism is false.
A short, but important, thought experiment clarifies:
Suppose a mad scientist exhaustively controls (causally determines) all of your thoughts and beliefs all the time. This includes exactly what you think of and about and exactly how you think of and about it. All of your thoughts about your beliefs and all of your beliefs about your thoughts are caused and determined by the mad scientist. This also includes the next words that will come out of your mouth.
Question: How can YOU (not the mad scientist) rationally affirm the current beliefs in your head as good, bad, better, the best, true, or probably true (note the range of options from which to choose) without begging the question?
Good luck with that… it is impossible!
Replace the mad scientist with “physics and chemistry,” “God,” or anything else and one has the exact same rationality problems but for different reasons. However, since humanity does possess the ability to rationally infer and affirm knowledge claims (to argue otherwise is to affirm it), we know that we possess the libertarian freedom to think and take certain steps while deciding what we ought to affirm and believe. And since libertarian freedom seems to be metaphysically impossible if humanity is nothing but physical stuff, we can rationally infer that humanity is more than merely the physical.
Stay reasonable (Isaiah 1:18),
 Evan Minton originally asked me this question in a previously recorded interview on the Cerebral Faith Podcast. I encourage all to listen to the interview in its entirety (click here).
 The FTA has been worded in several manners while each premise (and conclusion) remains functionally equivalent, sometimes different wording is offered for clarification. Here is another iteration, for example:
1- If humans are not free (in a libertarian sense), they cannot possess reason-based knowledge.
2- Humans can possess reason-based knowledge.
3- Therefore, humans are free (in a libertarian sense).
 Justification is often recognized as an essential ingredient if one is to possess propositional knowledge. Many affirm that although justification is required for knowledge, sometimes more is also required. However, if one is willing to bite the bullet and reject the idea that justification is required for this kind of knowledge, then the vital premise of the FTA can be amended to the following (or something similar) and still possess force:
1*- If humans do not possess libertarian freedom, then humans do not possess rational justification for their beliefs.
A good discussion regarding epistemology and related issues (What is knowledge?, What is justification?, Internalism vs. externalism, etc.), can be found here: https://plato.stanford.edu/entries/epistemology/ (accessed 10-1-19)
 Replacing the mad scientist with “physics and chemistry” is problematic since the forces of nature are non-rational. If non-rational forces are causally determining all the thoughts and beliefs in your head, including the thoughts and beliefs about your current thoughts and beliefs, then you (the thing you call “I”), stand in no position to rationally affirm your current thoughts and beliefs as good (option #1), better (option #2), the best, (option #3), or true (option #4).
If God is the one who is causally determining all the thoughts and beliefs of all people all the time, then, since all humanity holds some false beliefs — and some false beliefs have horrible eternal consequences, a version of the Omni Argument is waiting around the corner for the one who affirms exhaustive divine determinism (EDD). Thus, the EDD advocate will (at least tacitly) deny the maximal greatness of God. If this is the case, then there is not much difference between “god” (note the little “g”) and the mad scientist. If one affirms that God (note the big “G”) is a maximally great being, as I do, then they must reject EDD.