The dangers of non-empirical confirmation (2016) | Hacker News Reader

The dangers of non-empirical confirmation (2016)

arxiv.org

42 pointskergonath13 comments

Remember how medieval scholars would argue how many angels could dance on the head of a pin and craft beautiful logical arguments relying on their view of cosmology?

These weren’t dumb people. These were likely the smartest and best educated.

Tying theories to empirical science is what keeps logic grounded in reality.

I think you over-simplify the point a bit:purely intellectual considerations are still useful, be it Occam’s razor or a bias towards simplicity. I think I agree with the author in that non-empirical factors are useless for verification. You’d think that this should be obvious, but apparently not (this article is part of some continuous intellectual guerilla warfare around string theory*). OTOH, they are still useful when building or adjusting a theory.

This is really obvious when reading Einstein: relativity was verified a posteriori, but before then there were other aspects that made it seem right (simplicity, elegance, the ability to combine several apparently incompatible theories, etc). It certainly was not verified in 1905, when the paper on special relativity was published.

To take your example, arguing is fine, but the whole angel discussion should be proven empirically to be of any use. When we realise that it could not be proven, then it stops being science.

* with the author Carlo Rovelli arguing against string theory, being one of the authors of the quantum loop gravitation theory which also aims at unifying quantum mechanics and gravitation. He is a great scientific vulgarisation writer as well.

One detail:

When the special theory of relativity was published the problem of the aether, or rather that the speed of light was the same in all directions, was very well-known. This problem was very much based on empirical evidence.

Special relativity provided a mathematical framework within which that could be true, and included some further testable hypotheses, which were then still unproven. (Time slowing down for fast travellers etc.)

But I think it's fair to say that special relativity was developed due to empirical necessity.

I agree that special relativity was born out of a empirical question.

However, that a theory explains a certain known phenomenon does not really increase how trustworthy it is. It is trivial to construct a theory that explains a certain phenomenon, the it is slightly less trivial (that's a bit of an understatement) to construct one which does not contradict any other known phenomena. However to empirically "confirm" a theory requires that the theory predicts a phenomenon which has not been observed and is empirically observed.

I definitely agree. But we cannot really use (only) already-known facts to validate a theory. A theory built around such a fact will explain it by design and won’t have as much explanatory power as if the fact were verified after the theory is established. Of course if a theory cannot explain an already-known empirical fact, then it’d better provide a good explanation, like a different domain of validity.

Because of this, I would not consider relativity to have been validated until things like the Kennedy–Thorndike experiment. Even if it could already reconcile the principle of relativity and a constant speed of light, which was a significant intellectual achievement. Explaining the Michelson-Morley experiment was great, even a posteriori.

The conclusion that the types of things that can be arrived at empirically is preferrable to the conclusions of other means of reasoning, ironically enough, would not be possible to arrive at through empiricism alone, by virtue of is-ought.

I take your point, and now I am trying to decide if the effectiveness of empirical verification, in developing a robust consensus for conclusions so verified, is itself empirical evidence for preferring such conclusions, in domains where such verification is possible?

All else being equal, isn’t a theory clearly more valuable if its empirical validation is more accessible?

Stated inversely and ad absurdum, what use is a theory you can never prove?

This just moves the problem to empirically proving that that which is useful is preferable to that which is not.

You might say, "Ah, but you can empirically prove that you can do more with that which is useful", which is again true, but then you need to empirically prove that being able to do more is preferable.

After several more tedious steps, you end up at a position like "but I prefer this outcome over that", which may absolutely be true, but this is not something you've arrived at through experiments and observation, but is an experience in itself. In the end, the crux is that I can't construct an experiment that proves or disproves what it's like to be you (which is really a re-formulation of the hard problem of consciousness).

This line of argument also applies to any preference for an unverifiable theory, including unverifiable theories where a verifiable one exists.

What you are saying here seems to be the hard problem of philosophy, or at least analytic philosophy: how do you determine your axioms?

None of the medievals would have been dumb enough to ask how many pure spirits could dance on a head of a pin. Like much other folklore about the Middle Ages, this is almost certainly early modern propaganda.

> The libel about angels on the heads of pins seems to be of comparatively recent invention. I have not been able to find it in any author before Erasmus Darwin (who was late enough to have written, in his Visit of Hope to Sydney Cove, on the prospects for the spread of civilisation to New South Wales), though one might suspect the Encyclopedists or Rabelais as more likely originators of the idea. [Update] No medieval writer has been exhibited who engaged in such a dispute, for the good reason that there was none.

https://web.maths.unsw.edu.au/~jim/renaissance.html

to be fair, the arguing over imagined minutae isn't confined to metaphysical considerations. early astronomers with telescopes also argued about how many martiopogenic canals were on Mars and had mapped and named something like 300 of them

Not really related to Physics, but more relevant for anything less direct than the hard sciences: don't forget about the evil twin: the dangers of false empirical confirmation.

People, organizations, or just inherent bias will juke the stats. In terms of human impact, it's probably far more detrimental.

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