Abstract
Alexander Pruss’s Principle of Sufficient Reason (PSR) states that every contingent true proposition has an explanation. Pruss thinks that he can plausibly maintain both his PSR and his account of libertarian free will. This is because his libertarianism has it that contingent true propositions reporting free choices are (virtually) self-explanatory. But I don’t think Pruss can plausibly maintain both his PSR and libertarianism without a rift occurring in one or the other. Similar to the old luck/randomness objection, I contend that Pruss’s libertarianism is susceptible to what I call “the inexplicability objection”, which attempts to show that agents’ free choices involve contingent brute facts. Pruss may be able to partially explain a proposition such that Jones freely chose A for reason R, but he cannot adequately explain a contrastive proposition such as that Jones freely chose A for R rather than B for R*. The result is that either PSR is too explanatorily permissive for libertarianism, or libertarianism is too explanatorily impermissive to satisfy PSR. After considering what I take to be Pruss’s best response to the inexplicability objection, I conclude that his attempt to reconcile PSR and libertarianism is unsuccessful.
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Notes
To my knowledge, Pruss never characterizes his principle as a “Goldilocks” version of PSR, but I think the name nicely captures the sort of PSR that he is after.
In his most thorough treatment of free will, Pruss proposes two accounts of libertarianism, each alleged compatible with PSR (Pruss, 2006: 126–159): a Jamesian reasonless-choice account and a reasoned-choice account. Pruss admits that the former account is explanatorily unsatisfying and implausible in certain respects, preferring the latter account himself as being more defensible and promising (Pruss, 2006: 132–134, 137, 158–159, 184–185; cf. 2009: 54–56; cf. 2011: 233–234). Thereby, I’ll be restricting myself to the more plausible, reasoned-choice account (frequently referred to in this essay as “Pruss’s account” of libertarianism). The reasoned-choice account also comes in two versions amounting to the same thing (Pruss, 2006: 158, 185), but for my purposes I’ll restrict myself for the most part to one. “For the most part” because I’ll sometimes vacillate between the two versions in order to make clearer what Pruss’s account is. No harm is done in my doing so since (as Pruss concedes) the difference between the two versions comes down to a preference of how one phrases explanations. Furthermore, Pruss’s account isn’t only concerned with human free choices, but also divine free choices. However, I’ll be restricting myself to the former, although I do think my conclusion has import for the latter.
To perhaps further appreciate the discomfort with Pruss’s account, consider what a more promising if not more familiar candidate for a self-explanatory truth might look like, say, the necessary true proposition that 1 = 1. As Pruss has remarked, “1 = 1 is not a brute fact: there is no puzzle (not even an insoluble one) as to why it is true – once you see that 1 = 1, what is there to be puzzled about?” (Pruss, 2006: 123). It seems there are no outside details which must be sought to explain that 1 = 1 when understood, and so it’s a plausible candidate for a self-explanatory proposition. But contrast this with the alleged self-explanatory contingent true proposition that Jones freely chose A for R modulo K. Indeed, the former proposition is necessary, and the latter proposition contingent. Yet, what appears to make the former a candidate for self-explanation is, at least in part, its being a necessary true proposition, one impossible to be false. That explains why it is true rather false. But this feature is of course lacking in a contingent proposition. So, it may initially seem (as it does to me) that necessary true propositions are the only self-explanatory propositions if there are any at all.
Pruss seems committed to denying the possibility of W3. Jones’s ability to choose at t, despite her alternative being just as available to her, is what apparently makes her case paradigmatic of libertarian free will. But the above ternary-outcome case indicates (when generalized) that no agent makes a free choice when their alternatives are just as available to them, and thus that there are no paradigmatic instances of libertarian free will, contrary to Pruss’s supposition.
That agents choose among competitors according to the most impressing reasons would presumably explain why a number of outlandish, imaginable alternative choices available to Jones aren’t serious competitors when she obliges Smith: namely, because the extent to which Jones is impressed by those reasons are low or non-existent. For example, that Jones could freely choose to be malicious to Smith because Smith has a ridiculous haircut isn’t a very serious option in light of Jones and Smith being good friends, not to mention that Jones values compassion. In other words, Jones has little if any reason to be malicious to Smith.
The idea of contrastive explanation here is a rough adaptation of Peter Lipton’s “difference principle” (Lipton, 1993: 217).
Cases that one might take to show the limits of contrastive explanation as I’ve characterized it include, for example, the widely discussed syphilis-paresis case in the philosophy of science (cf. Liption 1993: 211, 224) or indeterministic interpretations of quantum theory (cf. Pruss, 2006: 160–170; and 2009: 58–59). It also wouldn’t be arbitrary to say that contrastive explanations don’t apply to such cases while applying to cases of libertarian choice. For at least one important difference between them is that the syphilis-paresis case or quantum indeterminacy need not appeal to intentional explanations, whereas libertarian choice does.
The point is worth highlighting because it avoids a cumbersome set of complications with contrasts (cf. Lipton, 1993) as well as a potential rebuttal from Pruss (2009: 59; cf. 2006: 148–155) to the effect that he is not committed via PSR to saying that every proposition is (implicitly) contrastive or that every sufficient explanation is contrastive (which may or may not be right).
Not to belabor the point, but the bruteness of Jones’s free choice might be made even more salient if we dispense with the idea that prior to her choice she is impressed by R and R* to an equal degree and rather suppose that Jones is impressed by R to a lesser degree than R* and yet chooses for R. Then mutatis mutandis, there’s a difference in the histories of W1 and W2, but surely not one that clears up our puzzlement over why it is the case that W1 rather than W2 is the actual world. Indeed, our puzzlement only deepens, and Jones’s choice looks as inexplicable as ever. Is this scenario consistent with Pruss’s libertarianism (cf. end of Section 3)? If so, then Jones’s choice to A is brute. If not, then my diagnosis from Section 7 appears to be further confirmed, which also served to motivate the idea that Jones’s choice to A is brute.
Even assuming Jones’s free will is a relevant difference from the bizarro Archimedean case, perhaps the disanalogy could be amended by supposing that God, say, bestows a relevantly similar libertarian-like power upon Archimedes’s scale.
References
Alexander, D. (2008). The Recent Revival of Cosmological Arguments. Philosophy Compass, 3(3), 541–550.
Bennett, J. (1984). A study of Spinoza’s ethics. Hackett Publishing Company.
Clarke, R. (1995). Indeterminism and control. American Philosophical Quarterly, 32, 125–138.
Della Rocca, M. (2003). A rationalist manifesto: Spinoza and the principle of sufficient reason. Philosophical Topics 31(1&2), 75–93.
Della Rocca, M. (2010). PSR. Philosopher’s Imprint 10(7), 1–13.
Della Rocca, M. (2008). Spinoza. Routledge.
Griffin, M.V. (2008). Necessitarianism in Spinoza and Leibniz.In Charles Huenemann (Ed.), Interpreting Spinoza: Critical essays (pp. 71–93). Cambridge University Press.
Kane, R. H. (1996). The significance of free will. Oxford University Press.
Kane, R.H. (2007). Libertarianism. In Fischer, M., Kane, R., Pereboom, D., Vargas, M. (Eds.), Four views on free will (pp. 5–43). Blackwell Publishing, Ltd.
Leibniz, G.W. (1989). Philosophical essays. Ariew, R., Garber, D. (Trans., Eds.). Hackett Publishing Company.
Lin, M. (2012). Rationalism and Necessitarianism. Nous, 46(3), 418–448.
Lin, M. (2018). The principle of sufficient reason in Spinoza. In Michael Della Rocca (Ed.) The Oxford Handbook of Spinoza (pp. 133–154). Oxford University Press.
Lipton, P. (1993). Contrastive explanation. In David-Hillel Ruben (Ed.), Explanation (pp. 207–227). Oxford University Press.
O’Connor, T. (2008). Theism and ultimate explanation: The necessary shape of contingency. Blackwell Publishing Ltd.
Pruss, A. (2011). Actuality, possibility, and worlds. The Continuum International Publishing Group.
Pruss, A. (2009). The Leibnizian cosmological argument. In Craig, W.L., Moreland, J.P., The Blackwell companion to natural theology (pp. 24–100). Blackwell Publishing, Ltd.
Pruss, A. (2006). The principle of sufficient reason: A reassessment. Cambridge University Press.
Van Inwagen, P. (1983). An essay on free will. Oxford University Press.
Acknowledgements
I’m very grateful to Michael Bergmann, Samuel Kahn, Vince Jacobson, Josh Folk, and the audience members of the Spring 2015 meeting of the Indiana Philosophical Association for their helpful comments on earlier versions of this paper.
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Rdzak, B. The Principle of Sufficient Reason and Libertarianism: A Critique of Pruss. Philosophia 50, 201–216 (2022). https://doi.org/10.1007/s11406-021-00364-0
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DOI: https://doi.org/10.1007/s11406-021-00364-0