If you'll recall, one answer is causal regularity:
Causal regularity: In order to have a science of, say, photons, photons must have some specific effects they produce by their very nature. If they had a different effect every time, then experiments could never reliably be extrapolated to every photon in the universe. When we do the double slit experiment on photons, we need to be able to say "this is what ALL photons would do under similar conditions." As a result, we can then have knowledge of the nature of photons.This means that something that has an effect must have that effect by its very nature. A few experiments on an object will reveal that nature, and its effect, which can then be extrapolated to all such objects of that type, thus making knowledge possible. We don't have to examine every single object of that type to know what it does.
If this principle were false, then an experiment involving one or a few photons could never be extrapolated to all photons, since each one might have a different effect.
This also entails that an object "points to" its effect (or range of effects), even if that effect is never in fact realized. So for example a match which is never struck nonetheless "points to" fire but not ice. Or a quantum vacuum "points to" the production of virtual particles but not elephants, even if it never actually produces any virtual particles. Or a volcano "points to" the production of magma but not tulips, even if it remains forever dormant.
Note also that these things may have other "accidental" effects. The volcano may cause bird migrations and mudflows, but these are side effects. Volcanoes by their very nature point to the venting of magma as their effect. If volcanoes did not do this then they just wouldn't be volcanoes. However, it could be the case that volcanoes never cause bird migrations or mudflows, but even so they would still be volcanoes. So some effects are mere side effects, but other effects are tied to the nature of the object in question.
There is a tight two-way correlation between cause and effect:
- A is the cause of B
- B is the effect of A
And a cause "points to" its effect:
- A "points to" B, even if B is never in fact realized
I apologize, as I know this post is more than a few months old, but I just discovered your blog. For me, this point is not as straightforward as it seems. Philosophers such as Popper would vehemently disagree that causal regularity is a necessary condition of science, though it does appear that the universe is regular. He would say that an experiment involving a few photons could NOT be extrapolated to all photons, and I would tend to agree. The assumption of causal regularity might be important, but that doesn't mean it is a true assumption.
ReplyDeleteThis statement towards the end provides a good illustration:
"Volcanoes by their very nature point to the venting of magma as their effect. If volcanoes did not do this then they just wouldn't be volcanoes."
While you view this as part of the nature of volcanoes, I view it as a part of what we mean when we talk about volcanos. There are certain things we observe that vent magma and we define those as volcanos. There are certain things which are pleasing to our noses and have thorns on their stems, those we call roses. All of this is descriptive.
As another example, look at the transitions in the fossil record from australopithecus to human. Do we point to one spot and say at that point we gained the nature of humanness? Or is it more accurate to simply describe the anatomy and habits we see at various points along the spectrum.
The "nature" of an object, in my view, simply means "what we observe it to be" and not anything teleological. When certain things share enough characteristics, we classify them into a group, despite whatever other differences they might have.
Thanks for your comment, Bradley.
ReplyDeleteI'm not sure why Popper and you would say that a few experiments on photons can be extrapolated to ALL photons, when in fact that is just what we do all the time. Open any physics textbook, and you'll find that photons (meaning: all photons) display both wave and particle characteristics when shot through the double slit. We (and scientists) don't say, "Hmmm. Well, the ones we've examined do this, but that's only those; maybe the others won't do that"
To have a science of photons, we need to be able to examine a few (by few I mean a few hundred or whatever) and then discover what photons do. Otherwise, we could never have a science of photons in general, since we still wouldn't know what the ones still out there do.
>There are certain things we observe that vent magma and we define those as volcanos.
"Those". A class. A species. A category. A is an X, and Xs do Y.
Substance and final cause.
> Do we point to one spot and say at that point we gained the nature of humanness?
Of course, human beings slowly "faded in", but that doesn't refute the fact that they exist now and can be categorized and have a certain nature (being smart, bipedal, etc).
>When certain things share enough characteristics, we classify them into a group
But if it's just us doing it, and isn't really "out there", then it would be explanatorily useless. But morpholgy is extremely useful, and the differences between an elephant and a flea are real, and not just an incident of us deciding to group together quarks arbitrarily. The whole science of evolution is based on morphology.
As to your first few comments, I would really recommend reading Popper, but I can give a general outline.
ReplyDeleteWe don't want to look in a physics book to understand the philosophy of science. To give a rudimentary example, physics books still teach newtonian mechanics because it works, but we have known for almost 100 years that it is wrong.
Popper states that Science advances through error elimination... we become less wrong as we go along.
He starts with a reformulating of Hume's problem of induction and concludes that no amount of testing will ever confirm that a theory is objectively true. The more severe testing a theory is able to withstand, the "better" the theory is, but there are plenty of examples in the past of "good" theories being wrong. and it only takes one legitimate counter example to invalidate a theory (see my comment on Newton above.)
We can't say that we know what ALL photons do, because we don't. We have a theory of photons that has withstood a large battery of tests, and based on that we accept that photons we encounter in the future will act the same way, until we observe otherwise.
>There are certain things we observe that vent magma and we define those as volcanos.
"Those". A class. A species. A category. A is an X, and Xs do Y.
Substance and final cause.
Let's switch from volcanos to something more germane. "Brunettes by their very nature grow brown hair as their effect. If brunettes didn't do that they just wouldn't be brunettes." Nature, in this instance, is an incredibly circular concept. I would certainly not say that the "final cause" of brown hair is that it is in the nature of brunettes to grow brown hair. That doesn't really explain anything.
I do think this boils down to the problem of universals. Are abstract objects "real"? I would be inclined to say that there is no ideal volcano above and beyond the individual volcanos that are / have been around. We understand what we mean when we say "volcano," but that is an observation on our knowledge, not volcanos.
> Do we point to one spot and say at that point we gained the nature of humanness?
Of course, human beings slowly "faded in", but that doesn't refute the fact that they exist now and can be categorized and have a certain nature (being smart, bipedal, etc).
I still don't see how this "nature" exists apart from the beings that instantiate it. Of course we can say that humans are smart bipeds, but why does that give them a "nature" beyond that of being, well, smart bipeds. We can classify people according to hair color, and there are REAL differences in hair color, but it doesn't seem to say anything profound about the universe.
>When certain things share enough characteristics, we classify them into a group
But if it's just us doing it, and isn't really "out there", then it would be explanatorily useless. But morpholgy is extremely useful, and the differences between an elephant and a flea are real, and not just an incident of us deciding to group together quarks arbitrarily. The whole science of evolution is based on morphology.
This reminds me of Plato's Statesman (maybe the Sophist, they are really similar). They go through a whole process of splitting things into groups, and the man from Elea discusses how important it is to split things along the proper lines. This might be a part of the job of science. Our groupings are of course not arbitrary, why would they be. We can make observations about the world, and those lead us to classify things in a certain way that is useful, and makes sense given what we are observing. I just don't see the need to invoke a "nature" beyond what we observe.
>based on that we accept that photons we encounter in the future will act the same way, until we observe otherwise.
ReplyDeleteSure. But THAT things have natures (final causes) does not entail that we can always KNOW those final causes 100%. Perhaps we will discover something new about photons, or how we were wrong. But even in that case, we would still be able to do a few experiments and then say "we were mistaken before, but now we think that THIS is what photons do." Again, science requires there to be classes, not just individuals. Even if the precise nature of the class can never be known.
>I would certainly not say that the "final cause" of brown hair is that it is in the nature of brunettes to grow brown hair. That doesn't really explain anything.
Indeed. The reason Descartes wanted to drop final causes altogether. However, just because they are explanatorily impotent does not meant that they are not real. It could be argued that they are unavoidable, because the only way to get rid of them is to say that they are not really out there but rather are just "projected by our minds", but then "projection by mind" is itself an example final causality, and so it ends up just moving them around without really getting rid of them. That is, at least, an argument that could be made.
> I would be inclined to say that there is no ideal volcano above and beyond the individual volcanos that are / have been around.
Implicitly, this series of articles is a mixture of neo-Platonism and Aristotelianism. So certainly the articles could agree with you that there is no "ideal volcano" over and above individual volcanoes, and simply hold to the moderate realism of Aristotle: the form "volcano" is IN each volcano, but does not exist over and above them.
>We can classify people according to hair color, and there are REAL differences in hair colo
The difference is accidental vs essential. Hair color is accidental: no matter what color hair they have, they would still be human. Just like what is essential to a triangle is to have three sides that add up to 180, but what color the triangle is is accidental. Doesn't affect what it is.
>Our groupings are of course not arbitrary, why would they be
If they are not arbitrary and they really do reflect some objective reality, then there really is structure out there above "the physical": plants, animals, boulders, etc. Not just clumps of quarks and electrons.