in almost all cases, you only ever have one theory on offer. In the case of gravity,

there literally is only one theory on offer at the moment. There's general relativity. Previously,

we did have two theories. We had Newtonian gravity and we had general relativity, but we did

a crucial experiment. This idea of crucial experiment is the cherry on top of science. You've got

these two competing theories and you have a particular experiment that if it goes one way,

one theory is ruled out, but the other theory is not. In which case, you keep that theory

for so long as no problems are right in. This vision of knowledge enables us to have an open

ended quest for progress, which is completely unlike any other idea about knowledge. The

overall majority of physicists are still Bayesian. The reason they're still Bayesian is because this

is typically what's taught in universities and this is what passes for an intellectually

rigorous way of understanding the world. But all it is is what I would call a species of

scientism, because they have a formula behind them based theorem, which is a perfectly

acceptable statistical formula. People use it all the time in perfectly legitimate ways.

It's just that it's not an epistemology. It's not a way of guaranteeing or even being confident

that your theory is actually true. My favourite example of this is prior to 1919, approximately.

Every single experiment that was done on gravity showed that it was consistent with Newton's

theory of gravity. What does a Bayesian say in that situation? What a Bayesian has to say is getting

more and more confident in Newton's theory. How does that make sense? How do you square that

circle of the day before it was shown to be false? Was the day when you were most confident in it?

Now, a paperian doesn't have this problem. A paperian just says, at no point was Newton's theory

actually true. It contains some truth, but that truth isn't a thing that we can measure. I say

it contains some truth, because it's certainly got more direct connection to reality than some

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