No one has ever come up with such a criterion
There are a number of useful terms for which no one has ever come up with a precisely stated and clearly defensible criterion. Beautiful, good, conscious, etc. This surely does indicate that there's something unsatisfactory about those terms, but I don't think the right way to deal with it is to declare that nothing is beautiful, good, or conscious.
Having said which, I think I can give a not-too-hopeless criterion distinguishing agents we might reasonably want to say have free will from those we don't. X has free will in regard to action Y if and only if every good explanation for why X did Y goes via X's preference for Y or decision to do Y or something of the kind.
So, if you do something purely "on autopilot" without any actual wish to do it, that condition fails and you didn't do it freely; if you do it because a mad neuroscientist genius has reprogrammed your brain so that you would inevitably have done Y, we can go straight from that fact to your doing Y (but if she did it by making you want to do Y then arguably the best explanation still makes use of that fact, so this is a borderline case, which is exactly as it should be); if you do it because someone who is determined that you should do Y is threatening to torture your children to death if you don't, more or less the same considerations apply as for the mad neuroscientist genius (and again this is good, because it's a borderline case -- we might want to say that you have free will but aren't acting freely).
What does this criterion say about "normal" decisions, if your brain is in fact implemented on top of deterministic physics? Well, an analysis of the causes of your action would need to go via what happened in your brain when you made the decision; there would be an "explanation" that just follows the trajectories of the elementary particles involved (or something of the kind; depends on exactly what deterministic physics) but I claim that wouldn't be a good explanation -- in the same way as it wouldn't be a good explanation for why a computer chess player played the move it did just to analyse the particle trajectories, because doing so doesn't engage at all with the tree-searching and position-evaluating the computer did.
One unsatisfactory feature of this criterion is that it appeals to the notions of preference and decision, which aren't necessarily any easier to define clearly than "free will" itself. Would we want to say that that computer chess player had free will? After all, I've just observed that any good explanation of the move it played would have to go via the process of searching and evaluation it did. Well, I would actually say that a chess-playing computer does something rather like deciding, and I might even claim it has a little bit of free will! (Free will, like everything else, comes in degrees). Still, "clearly" not very much, so what's different? One thing that's different, though how different depends on details of the program in ways I don't like, is that there may be an explanation along the following lines. "It played the move it did because that move maximizes the merit of the position as measured by a 12-ply search with such-and-such a way of scoring the positions at the leaves of the search tree." It seems fair to say that that really is "why" the computer chose the move it did; this seems like just as good an explanation as one that gets into more details of the dynamics of the search process; but it appeals to a universal fact about the position and not to the actual process the computer went through.
You could (still assuming determinism) do something similar for the choices made by the human brain, but you'd get a much worse explanation -- because a human brain (unlike the computer) isn't just optimizing some fairly simply defined function. An explanation along these lines would end up amounting to a complete analysis of particle trajectories, or maybe something one level up from that (activation levels in some sophisticated neural-network model, perhaps) and wouldn't provide the sort of insight we seek from a good explanation.
In so far as your argument works, I think it also proves that the incompatibilists are wrong. I've never seen a really convincing incompatibilist definition of "free will" either. Certainly not one that's any less awful than the compatibilist one I gave above. It sounds as if you're proposing something like "not being reliably predictable", but surely that won't do; do you want to say a (quantum) random number generator has free will? Or a mechanical randomizing device that works by magnifying small differences and is therefore not reliably predictable from any actually-feasible observations even in a deterministic (say, Newtonian) universe?
I don't think the right way to deal with it is to declare that nothing is beautiful, good, or conscious.
Yes, obviously. But it is also a waste of time trying to get everyone to agree on what is beautiful, so too it is a waste of time trying to get everyone to agree on what is free will. Like I said, it's really quibbling over terminology, which is almost always a waste of time.
...Having said which, I think I can give a not-too-hopeless criterion distinguishing agents we might reasonably want to say have free will from those we don't. X has free will in
[Originally published at Intentional Insights in response to Religious and Rational]
Spirituality and rationality seem completely opposed. But are they really?
To get at this question, let's start with a little thought experiment. Consider the following two questions:
1. If you were given a choice between reading a physical book (or an e-book) or listening to an audiobook, which would you prefer?
2. If you were given a choice between listening to music, or looking at the grooves of a phonograph record through a microscope, which would you prefer?
But I am more interested in the answer to a third question:
3. For which of the first two questions do you have a stronger preference between the two options?
Most people will have a stronger preference in the second case than the first. But why? Both situations are in some sense the same: there is information being fed into your brain, in one case through your ears and in the other through your eyes. So why should people's preference for ears be so much stronger in the case of music than books?
There is something in the essence of music that is lost in the translation between an audio and a visual rendering. The same loss happens for words too, but to a much lesser extent. Subtle shades of emphasis and tone of voice can convey essential information in spoken language. This is one of the reasons that email is so notorious for amplifying misunderstandings. But the loss in much greater in the case of music.
The same is true for other senses. Color is one example. A blind person can abstractly understand what light is, and that color is a byproduct of the wavelength of light, and that light is a form of electromagnetic radiation... yet there is no way for a blind person to experience subjectively the difference between red and blue and green. But just because some people can't see colors doesn't mean that colors aren't real.
The same is true for spiritual experiences.
Now, before I expand that thought, I want to give you my bona fides. I am a committed rationalist, and an atheist (though I don't like to self-identify as an atheist because I'd rather focus on what I *do* believe in rather than what I don't). So I am not trying to convince you that God exists. What I want to say is rather that certain kinds of spiritual experiences *might* be more than mere fantasies made up out of whole cloth. If we ignore this possibility we risk shutting ourselves off from a vital part of the human experience.
I grew up in the deep south (Kentucky and Tennessee) in a secular Jewish family. When I was 12 my parents sent me to a Christian summer camp (there were no other kinds in Kentucky back in those days). After a week of being relentlessly proselytized (read: teased and ostracized), I decided I was tired of being the camp punching bag and so I relented and gave my heart to Jesus. I prayed, confessed my sins, and just like that I was a member of the club.
I experienced a euphoria that I cannot render into words, in exactly the same way that one cannot render into words the subjective experience of listening to music or seeing colors or eating chocolate or having sex. If you have not experienced these things for yourself, no amount of description can fill the gap. Of course, you can come to an *intellectual* understanding that "feeling the presence of the holy spirit" has nothing to do with any holy spirit. You can intellectually grasp that it is an internal mental process resulting from (probably) some kind of neurotransmitter released in response to social and internal mental stimulus. But that won't allow you to understand *what it is like* any more than understanding physics will let you understand what colors look like or what music sounds like.
Happily, there are ways to stimulate the subjective experience that I'm describing other than accepting Jesus as your Lord and Savior. Meditation, for example, can produce similar results. It can be a very powerful experience. It can even become addictive, almost like a drug.
I am not necessarily advocating that you go try to get yourself a hit of religious euphoria (though I wouldn’t discourage you either -- the experience can give you some interesting and useful perspective on life). Instead, I simply want to convince you to entertain the possibility that people might profess to believe in God for reasons other than indoctrination or stupidity. Religious texts and rituals might be attempts to share real subjective experiences that, in the absence of a detailed modern understanding of neuroscience, can appear to originate from mysterious, subtle external sources.
The reason I want to convince you to entertain this notion is that an awful lot of energy gets wasted by arguing against religious beliefs on logical grounds, pointing out contradictions in the Bible and whatnot. Such arguments tend to be ineffective, which can be very frustrating for those who advance them. The antidote for this frustration is to realize that spirituality is not about logic. It's about subjective experiences that not everyone is privy to. Logic is about looking at the grooves. Spirituality is about hearing the music.
The good news is that adopting science and reason doesn’t mean you have to give up on spirituality any more than you have to give up on music. There are myriad paths to spiritual experience, to a sense of awe and wonder at the grand tapestry of creation, to the essential existential mysteries of life and consciousness, to what religious people call “God.” Walking in the woods. Seeing the moons of Jupiter through a telescope. Gathering with friends to listen to music, or to sing, or simply to share the experience of being alive. Meditation. Any of these can be spiritual experiences if you allow them to be. In this sense, God is everywhere.