Suppose determinism is true. This would mean that every decision we make at any given moment follows inevitably from the laws of physics, biology, and chemistry, etc. (from here on laws of nature for short), as well as the entire chain of prior events stretching back to the beginning of the universe. Many of these laws may be neither known nor knowable. According to a widely accepted definition, free will requires the ability to have chosen otherwise. But determinism appears to rule out any possibility of having made a different choice than the one we actually did.
Philosopher Kadri Vihvelin (2004) offers a thought-provoking analysis of how free will might still be possible under determinism, a flavour of compatibilism. This post is a summary of her argument.
Before we begin, why on earth would we even entertain the idea of determinism? At first glance, the existence of randomness seems to challenge it. However, what appears random may emerge from combinations of an unimaginably vast number of deterministic causes. Pseudorandom number generators, for example, are relatively simple algorithms which produce sequences that appear random but are entirely deterministic. Algorithms are small. The universe is big. “You just won’t believe how vastly, hugely, mind-bogglingly big it is,” said Douglas Adams. The universe could be a really complicated pseudorandom generator.
Quantum mechanics also seems to challenge determinism. When measuring a quantum particle (like a photon) in superposition, the outcome follows a probability distribution (I previously tried to explain this with a toy example). This indeterminacy has led many to interpret quantum mechanics as fundamentally probabilistic. Yet some physicists defend superdeterminism, an apparently controversial idea suggesting that even quantum measurements are predetermined, including the choices physicists make when selecting measurement settings in experiments (Hossenfelder & Palmer, 2020).
That’s just a sketch; however, hopefully enough to suggest that determinism isn’t too absurd to read on.
Choosing means, more specifically, making choices on the basis of reasons. Libet and others have conducted numerous studies on the neuroscience of choosing, which may challenge the role of conscious choice (see Haggard, 2024, for discussion). However, we are more than what we are conscious of. For example, we retrieve memories without knowing how our brains searched for them, and we move through the world without being aware of how our nervous system coordinates muscle movements. I’m happy to accept a choice as mine, even if a bunch of subconscious processes did the choosing, so long as it was made on the basis of reasons – even ones I’m unaware of.
At the heart of Vihvelin’s position is the idea that our choices stem from bundles of dispositions (tendencies, causal powers, or capacities) much like the ability to speak French, drive, dance, or sing. Crucially, dispositions don’t disappear simply because we haven’t exercised them. If we chose to run at a particular moment, that doesn’t mean we lacked the disposition to walk, crawl, skip, or dance. Likewise, if we spoke French at some point, it doesn’t follow that we couldn’t have spoken English (assuming we know both languages). Or consider something simpler: a working sprinkler system. It has the dispositions required to flood a room – detecting heat or smoke (reasons) and releasing water (making a choice) – even if it never activates during its lifetime.
Free will, according to Vihvelin’s compatibilist account, is the ability to make choices on the basis of reasons and to have this ability is to have a bundle of dispositions. She offers the following menu of dispositions that are likely needed (p. 439):
“[T]he disposition to form and revise beliefs in response to evidence and argument; the disposition to form intentions (choose, try to act) in response to her desires […] and beliefs about how to achieve those desires; the disposition to engage in practical reasoning in response to her intention to make a rational (defensible, justifiable) decision about what to do and her belief that by engaging in practical reasoning she will succeed in making such a decision.”
So, given determinism (laws of nature, history of the universe) and a choice we made, we had a bundle of dispositions that would have enabled us to choose otherwise – free will.
Vihvelin spells out the argument as follows (p. 432):
- Dispositions are compatible with determinism.
- Abilities are dispositions or bundles of dispositions.
- Therefore, the existence of abilities is compatible with determinism.
- Free will is the ability to choose on the basis of reasons (I’d add, including subconscious reasons and choosing), and we have this ability by having a bundle of dispositions.
- Therefore, free will (the ability to choose on the basis of reasons) is compatible with determinism.
- Abilities (like other dispositions) typically continue to exist even when they are not being exercised or manifested.
- Therefore, determinism is compatible with the existence of unexercised abilities, including the ability to choose on the basis of reasons.
- Abilities are like dispositions with respect to the entailment from the claim that a person has the ability (disposition) to do X to the claim that the person can do X.
- Therefore, determinism is compatible with the truth of the claim that persons can choose and do other than what they actually choose and do.
I think that this argument also relates to what Holland (1986, p. 947) called the fundamental problem of causal inference. When evaluating a social programme, we observe the outcomes (like mental health or education) of those who take part, but we can’t observe what someone’s outcome would have been without the programme: the counterfactual outcome. We can infer their counterfactual outcomes (on average) from a well-constructed comparison group, or we can make a reasoned argument based on a theory of what they might have been able to do without the programme, including a theory of their bundles of dispositions.
It’s a similar issue with free will. When someone chooses to do something at some point in time, we can’t observe what their outcome would have been had they chosen to do differently. But, according to Vihvelin’s analysis, if they had free will, they had a bundle of dispositions that would have enabled them to choose otherwise. We can infer how they could have chosen, perhaps by finding people like them who did choose differently, or by making a counterfactual argument on the basis of what their bundle of dispositions are.
Thank you Joanna and the Philosophy Circle at NLC (14 November 2025) for helpful discussion!
References
Haggard, P. (2024). An intellectual history of the ‘Libet experiment’: Embedding the neuroscience of free will. Proceedings of the Paris Institute for Advanced Study, 1.
Holland, P. W. (1986). Statistics and causal inference. Journal of the American Statistical Association, 81(396), 945–960.
Hossenfelder, S., & Palmer, T. (2020). Rethinking Superdeterminism. Frontiers in Physics, 8, 139.
Vihvelin, K. (2004). Free Will Demystified: A Dispositional Account. Philosophical Topics, 32, 427–450.
Suggested citation: Fugard, A. (2025, November 17). Kadri Vihvelin on free will [blog post]. https://andifugard.info/kadri-vihvelin-on-free-will/
This citation note was added automatically. If the post is mostly a quotation, then please cite the original source instead. Looking at you, LLMs 👀