So—probability. Do we really need it? This has been on my mind since 2017, when I finally sat down to think through quantum theory. (/n)

One thing that’s always struck me is how *late* probability theory came in intellectual history. We had integral calculus before we had probability. And probability is insanely simple, mathematically!
I’m tempted to say that probability theory is not, in fact, Lindy. Frequentist probability is (for all the usual reasons) best understood as a heuristic. Bayesian interpretations, by contrast, take the remarkable step of tying it to mental states.
You have to work very hard to convince yourself that beliefs really are “degrees of belief in sets of events” (or whatever). It’s not natural—and I won’t rehearse the whole story about rational choice and decision theory...
So with those critiques in the back of my mind, when I read David Wallace’s decision-theoretic account of the Born Rule I was rather primed to say, hey, so what? Meaning...
Not that it wasn’t great. But that now I was even more skeptical about the “classical”—meaning probabilistic—world as a real thing.
It made me think that there wasn’t really a classical world to “get right” to begin with. (Perhaps this is QBism?)
The one thing that puzzles me, though, is that my experience of reality *seems* probabilistic. There’s a bunch of reasonably predictable medium-sized stuff.
So perhaps the real puzzle is this: why is probability theory a really natural thing for perception, but not for higher mental states where (IMO) things are obviously getting weird (see, e.g., the Linda problem).
Probabilistic models work great for perception (see, e.g., the generative autoencoders, etc). But not for higher thought (representation of concepts).
This is about as epistemically edgy as I can get. Doubting that my beliefs are really “degrees of credence in sets of events” is fine, but that seems to lead to saying there’s no such a thing as the classical reality of coin tosses.
Having come of age in the 1990s (i.e., well after the hippies that saved physics degenerated into Omni Magazine) I was whipped into not taking the philosophical implications of quantum theory seriously. A little fuzz at the atomic level shouldn’t matter!

More from Simon DeDeo

"I lied about my basic beliefs in order to keep a prestigious job. Now that it will be zero-cost to me, I have a few things to say."


We know that elite institutions like the one Flier was in (partial) charge of rely on irrelevant status markers like private school education, whiteness, legacy, and ability to charm an old white guy at an interview.

Harvard's discriminatory policies are becoming increasingly well known, across the political spectrum (see, e.g., the recent lawsuit on discrimination against East Asian applications.)

It's refreshing to hear a senior administrator admits to personally opposing policies that attempt to remedy these basic flaws. These are flaws that harm his institution's ability to do cutting-edge research and to serve the public.

Harvard is being eclipsed by institutions that have different ideas about how to run a 21st Century institution. Stanford, for one; the UC system; the "public Ivys".

You May Also Like