At one point I had the idea that I was going write a bunch of For The Record posts — position papers that attempt to be final words on a topic (at least until new considerations came into play). Other one about guns (back in 2015), I never really followed through.
In a sense, all posts, are final words (until further consideration), so all posts can be seen as FTR. The question is whether it makes any sense to mark an expressed opinion as more official or duly considered rather than off the cuff or casual. That was my thought, anyway.
So, seven years later, FTR take two: Free Will
Perhaps, as with the guns post, what justifies labeling this as FTR is the sense in my mind of the resolution of a question I’ve been pondering for a long time.
With guns, for instance, my upbringing tended towards “who needs them” semi-neutrality or focusing on the social negatives (which certainly exist). But my personal interests (fueled by friends) led me towards positive views. The upshot was years sitting on the fence thinking about it. After duly considering the matter, I picked a lane.
The issue of free will is another topic that I’ve spent years pondering (and posting about), although in this case it wasn’t trying to decide between pro or con but trying to reconcile notions of causal determination with our abiding sense of free will. If one is to take the latter seriously, one must provide a sensible mechanism for it. Or else explain that sense.
And that’s what’s FTR here. Fixing on a putative mechanism.
To be clear, it’s just a story I’ve made up, but it’s one that tries to fit physical fact, requires nothing new, and explains how we might legitimately have free will (as it certainly feels we do).
I define free will as the ability to make a genuinely arbitrary choice given all past information — to pick between possible futures. If we could rewind reality to some decision point, physics would allow a different choice. There is nothing inevitable about human choices.
The question I’ve pondered for years is: How? What is the mechanism of choice?
If brains are not deterministic, how do they escape it?
A computer presented with a given set of inputs always makes the same choices. Those choices, based on its software, can be predicted in advance. (They were predicted in advance by the software designer.) The computer has no free will.
When it comes to the human brain, people ask whether sufficiently complex software wouldn’t behave as if it had the same kind of apparent free will humans demonstrate. Can complex enough software appear to select among options based on subtle factors? Yes, absolutely, but, as far as I know, the behavior of such remains fully deterministic. Given the same inputs, we get the same outputs. The implication, of course, is that brains are the same.
So, mind models based on computers don’t seem to offer a path to free will. The perception that the brain is a computer leads to the perception that our minds must be deterministic.
But the brain obviously isn’t a computer in any traditional sense. We’d be much better at math and logic if it was. (Seeing neurons as individual computers makes some sense, though.) Brains don’t function in the stored-program-and-CPU way of computers but as vast massively parallel real-time networks. In fact, that we’re bad with math might be an important clue.
[One thing software seems missing is understanding. Some of the most recent networks are very powerful (yet often fragile). They appear capable of not just recognizing but creating images and text. But so far nothing seems to contain a hint of understanding or context about the choices or creations. They are still the “Chinese Rooms” Searle spoke of.]
From a physics point of view, either reality is fully deterministic (and therefore has no surprises in the future — our abiding sense of free will is an illusion) or it has quantum randomness (and the future is based on probabilities).
Random choices aren’t what we mean by free will, so it’s hard to see how quantum randomness helps. It’s certainly possible to amplify a quantum result, a spin measurement, for instance, and to use it to determine our actions, but that’s the same as flipping a coin — it’s not free will. (Free will would be flipping the coin and then choosing to ignore it.)
An appeal to chaos amplifying quantum randomness to classical levels still requires an explanation for how that allows us to choose among options.
That’s the question I’ve chewed on many times deciding what to have for dinner. What mechanism (free or not) is behind the choice I make? Many of our choices are driven by imperatives that constrain us, but what to have for dinner seems far less restricted. Especially when I’ve decided soup the choice of which kind seems without consequence — about as free a choice as one could make.
Yet it doesn’t feel random. I wouldn’t want to blindfold myself and pick a can randomly; I want to choose which soup to eat. There is an active life-charting process involved, but what’s the mechanism?
Well, here’s the story I’ve decided on. It works for me and (until further considerations) I’m done thinking about it.
Firstly, I accept that reality at the quantum level is random. Regardless of preferred interpretation of quantum mechanics, we experimentally live in a reality that follows the Born rule. At the fundamental level, interactions are not deterministic.
[Back in April I posted five articles exploring the quantum conundrum of measurement — how a quantum system on its own evolves deterministically but when interacting with another system experiences probabilistic “collapse” of the wavefunction. The point here is that these interactions occur constantly.]
Secondly, chemistry is quantum. That’s easy to forget because chemistry seems so normal to us, but atoms are quantum objects and their electrons, which are the basis of most of their interactions, especially so. Modern chemistry fully embraces its quantum nature.
Yet chemistry is generally viewed as deterministic — do the same thing, get the same result. I suspect, however, that’s more a statistical truth than an atomic one. Similar to thermodynamics and entropy, which are the statistics of gazillions of particles, chemistry is the statistics of gazillions of atoms.
I further suspect the complex chemistry of biology magnifies quantum randomness (through chaos) and is even more subject to only a statistical type of determinism, one true only in virtue of sheer numbers. The world of particles might be deterministic (except that it isn’t), but I’m dubious about complex chemistry, and I have serious doubts about biology.
Thirdly, brains depend on complex biological chemistry, and by now we’re many levels of organization above the quantum level. So much so it might seem to have averaged out any quantum effects. The brain seems to be a classical device operating according to classical physics. We’re not currently aware of any special quantum magic happening in the brain (it isn’t a quantum computer).
But the brain is an incredibly complicated classical device, both in terms of numbers (of neurons) and in terms of weighted relationships (synapses) between its numbers. No other object, natural or human-made, comes close.
All systems are subject to noise, and reality tends to be especially noisy. Low-level noise can be amplified by chaos if it isn’t damped by averaging over or some form of hysteresis. Tiny effects can “tip” a system that has energy and is poised in a metastable balance point. Such systems can react strongly to gentle nudges. Imagine a plate balanced on the edge of table so needs only a tiny shake of the table to overbalance and fall.
Brains appear to operate in a metastable equilibrium space between chaotic noise and clocklike regularity. They’re extremely active devices — very busy all the time — and small nudges can have large results. Consider how a scent, a song, or a suggestion, can send your mind to strong past memories or imagined fancies.
Fourthly, the symbols brains process are ideas, thoughts, notions, feelings, qualia. Minds are noisy at this level — thoughts relevant and irrelevant constantly sleet through them. We may focus on a task, a book, a conversation, but other thoughts always bubble up.
[There are activities, meditation or playing music for instance, when it’s possible to either completely blank the mind or to be “in the zone” — a mental state that transcends thoughts.]
Our minds also build models of reality, including and very importantly, models of future reality. We’re able to vividly imagine possible futures.
Putting it all together, minds are noisy at all levels. As a result, they are constantly roiling with thoughts. When we consider a choice, we invoke and focus on possible options and results. And all the noise and linked associations that go with them.
It’s as if we balance these possible futures like plates along the edge of the table, all poised to tip off. Or in this case, poised to be selected. We jostle the table until one falls.
The noise of our mind introduces a bit of randomness or uncertainty within the parameters of that choice. The closer the options of the choice, the more noise might affect the outcome. Yet, even when a choice seems pretty clear, we’re capable of being capricious and choosing on a whim. We might think of that as a noise spike.
Rational people typically make rational choices among possible options (except for noise spikes), but sometimes all options are reasonable, and we’re left to decide what we prefer. For instance, having picked soup, picking which type of soup. There are the various influences: What haven’t I had in a while (I like variety); What kind of day is it (cold or warm); How hungry am I; and so on. But ultimately the choice seems whimsical, and I think that’s where the mental noise is a factor.
And that noise isn’t exactly random — it’s my noise. It’s noise that arises from my mental network, and it’s heavily flavored by my gestalt. So, while there may be some degree of randomness (whimsy) here, it’s strongly biased by the mind it occurs in. Our choices always reflect us.
If one doesn’t believe reality is fully determined, then it follows that brains aren’t. If the value of brains is allowing their owner to successfully navigate unpredictable reality, then it makes sense brains would evolve to handle that with creative responses.
Evolution adds an element of surprise through mutation, and it may have stumbled on a mechanism that allows true originality in living beings. The very notion of a “random mutation” might describe original thinking. Our minds are creative because they’re noisy, sloppy, and capable of error. We’re bad at math but great at imagining new stuff. That’s the astonishing wonder of being human.
Stay noisy, my friends! Go forth and spread beauty and light.