Wednesday, October 1, 2008

Eddington's Two Tables

As far back into my childhood as I remember thinking about such things, I thought of the physical objects around me as made up of particles. I learned last night, in talking to various philosophers, that this attitude in childhood is not universal. In fact, apparently, many educated people have Aristotelian intuitions that material objects are solid and continuous through and through, and while they can think the particle hypothesis, it does not come naturally to them.

This is an interesting case of how theory-laden the "intuitive" can be. To me, it is entirely intuitive to see an object as a bunch of particles, though I wouldn't say that I have a positive intuition that it is so—just a pervasive belief. At the same time, this is a belief I need to think myself out of (and into a suspension of judgment) because I do not think current physics gives one good reason to think there are particles.

This little case study is kind of scary to me. For instance, right now it seems entirely intuitive that space-time be a four-dimensional manifold, with time being ontologically on par with other dimensions. In fact, I've gotten to the point where a philosophical statement that says something like "substance S has accident A at time t" seems clearly incomplete: I want to know which reference frame this is in, and how the accident is spread out in a space-like hypersurface.

But since these intuitions are highly dependent on a physics that might turn out to be wrong (quantum theory and relativity theory are not both true, since they are incompatible), I need to be more open to three-dimensionalist ideas, which I find kind of scary. Three-dimensionalist ideas induce a kind of conceptual vertigo in me—the thought that I am this three-dimensional object in some kind of flow of time is weird, though I do of course think such metaphors sometimes.


Mike Almeida said...

Something interesting here. It is perfectly possible that your particle intuition is correct, but that gunk theory is true. It might be that your intuition is not that objects are ultimately composed of particles that are simples. In fact, I doubt that you were thinking there were ultimately simples in the world. It is more likely that your intuition was that there were smaller items--particles--into which physical objects can be decomposed whether or not those particles themselves could be decomposed. If that's what the intuition was about, it was perfectly reliable, even if ultimately everything is gunky.

Anonymous said...

"At the same time, this is a belief I need to think myself out of (and into a suspension of judgment) because I do not think current physics gives one good reason to think there are particles."

Would you mind explaining what you mean here? The first response that comes to mind is that our current theories have a lot of explanatory power. While usefullness does not imply truth necessarily, it seems like a good inductive argument towards the conclusion.

Alexander R Pruss said...

I don't think it's correct at this stage of the game to say that the best physics theories we have says that there are particles. It is at this point quite possible that a field theory that has no room for particles will win out. So I am not expressing a general scepticism about physics. I am simply saying that it is no longer true to say things like "physics tells us that there are particles."

Enigman said...

yeah, logic tells us there are individuals

Anonymous said...

Dr. Pruss,

Gotcha. Being ignorant of such matters, I didn't realize there was so much diversity in the theories of modern science. Thanks for the information.

Heath White said...

Man, Alex, you are wierd. :-)

Enigman said...

On particles, there's a lot of evidence for the atomic theory of matter, which may be all that Eddington's two tables requires. Although on that theory the table would seem to be continuous stuff because its physical chemical properties come from its electron shells, and they are all blurred together by the chemical bonds that hold the table together being composed of uncollapsed electrons.

On 3-dimensionalism, your 'conceptual vertigo' is presumably not that you, for example, derive some psychological security from Fatalism. Is it that spacetime is simpler than a temporal space? If so it may be akin to what materialists must feel when they contemplate substantial dualism. The things is, physics is substantially dualistic anyway, with its space-time and its mass-energy. (Maybe the only way to avoid such verigo is to be a Buddhist!)