The Dark Room Problem in neuroscience goes something like this: suppose the brain is minimizing prediction error, or free energy, or whatever. You can minimize lots of things by sitting quietly in a dark room. Everything will be very, very predictable. So how come people do other things?
The usual workaround is inbuilt biological drives, considered as "set points". You "predict" that you will be well-fed, so getting hungry registers as prediction error and brings you out of your dark room to eat. Et cetera.
Andrés Gómez Emilsson recently shared a perspective I hadn't considered before, which is: actually, sitting quietly in a dark room is really great.
The Buddha discussed states of extreme bliss attainable through meditation:
Secluded from sensual pleasures, secluded from unwholesome states, a bhikkhu enters and dwells in the first jhāna, which is accompanied by thought and examination, with rapture and happiness born of seclusion (Samyutta Nikaya)
I had always figured that "sensual pleasures" here meant things like sex. But I think maybe he just means stimuli, full stop. The meditator cuts themselves from all sensory stimuli, eg by meditating really hard on a single object like the breath and ignoring everything else, and as a result gets "rapture and happiness born of seclusion".
The serious meditators I know say this is real, meaningful, and you can experience it after a few months of careful practice. You become really good at concentrating on one stimulus and ignoring all other stimuli, and eventually your brain kind of gets "in tune" with that stimulus and it's really blissful. They say this seems to have something to do with the regularity or predictability of the stimulus; if you're concentrating really hard on something, regularity/predictability/symmetry is just viscerally very good, better than anything you've felt before.
Andrés takes this pretty literally. Something like regularity/predictability/symmetry is really good. So why doesn’t a metronome make you bliss out? Andrés says it’s because you can’t concentrate on it hard enough. It’s not engaging enough to occupy your whole brain / entire sensorium /whatever.
Symphonies are beautiful, and we intuitively feel like it’s because they have some kind of deep regularity or complicated pattern. But they’re less regular/predictable/symmetrical than a metronome. Andrés thinks this is because they hit a sweet spot: regular/symmetrical/predictable enough to be beautiful, but complex/unpredictable enough to draw and hold our attention. Compare to eg games, which are most fun when they’re hard enough to be challenging but easy enough to be winnable.
But this sweet spot is the fault of your own inattentiveness. If you could really concentrate on the metronome, it would be even more blissful than the symphony. Emilsson says he’s achieved these levels of concentration and can confirm. I talked to another meditator who agrees metronomes can be pretty blissful with the right amount of (superhuman) focus, although - as per the Buddha quote above - total silence is best of all.
I find this to be an elegant explanation of what the heck is going on with jhanas, more convincing than my previous theory. It’s also a strong contender as a theory of beauty - a little different in emphasis from Schmidhuber’s theory, but eventually arriving at the same place: beauty is that which is compressible but has not already been compressed.