Author Archive

Articles

Quick question on Zach’s Paper

In Uncategorized on April 19, 2010 by Leo

Since I think we’ll be talking mostly about Yasha’s paper tomorrow, here’s a quick question I had on Zach’s paper:

Zach’s paper distinguishes between two game-theoretic approaches: the static approach and the dynamic approach. The static approach focuses on characteristics of the strategy itself. The dynamic approach focuses on how players settle on a particular strategy. However, it is unclear to me whether or not these are actually two distinct approaches. Is it not the case that the dynamic approach merely specifies which of the equilibria already picked out by the static approach that players will actually converge on? That is, does the dynamic approach actually subsume the static approach, by first identifying all the possible equilibria, and then improve upon it by identifying a subset of those equilibria which will end up being chosen by the players given certain initial conditions?

Articles

Another basic confusion

In Uncategorized on March 23, 2010 by Leo

Like Jenny I also have a basic question that I hope can be resolved fairly easily.

Lewis says that causal “dependence consists in the truth of two counterfactuals: O(c) [] -> O(e) and ~O(c) [] -> ~O(e).” (563) Here the O(c) and O(e) refer to families of events. Lewis then goes on say that if we refer not to families but individual events c and e and if we assume further that the individual events c and e are actual, then the first counterfactual in the quote above is automatically true and that this leaves us only with the second counterfactual to deal with. “But if c and e are actual events, then it is the first counterfactual that is automatically true. Then e depends causally on c iff, if c had not been, e never had existed.” (563)

Maybe its just my intuitions but it feels like there’s a jump between positing the first counterfactual requirement in terms of individual events: “e would have occurred if c had occurred” and fulfilling that counterfactual requirement by merely stipulating that in this particular world both e and c have occurred, especially if we’re making claims about causality. Just because e and c have occurred doesn’t seem to mean the same thing as “if c had occurred then e would have occured”. I’ve talked with Josh about this and I think he shares this intuition as well. Does this seem to anyone else to be a bit shifty?

Articles

Connection between Pincock and Weisberg?

In Uncategorized on March 16, 2010 by Leo

Part of Pincock’s article struck me as quite similar to Weisberg’s robustness analysis and I wanted to see if people thought these similarities are actual, relevant, or important.

Pincock argues that even his revised indispensability argument falls short of allowing us to accept the conclusion that scientific practice gives us good reason to believe the truth of some mathematical claims. This is because the argument is question begging. The only way to avoid this question begging is to justify the mathematical claims independently from their indispensable explanatory role in science. “I want to argue that our justification for a given mathematical claim cannot depend entirely on its contribution to a scientific explanation. This is because the claim must be independently justified for it to make this contribution to the explanation… explanatory contributions can only provide additional boosts in justification for a belief that was already substantially justified.” (9)

This sounds a bit like Weisberg in “Robustness Analysis” when he defends RA against O&S’s claim that RA is a form of non-empirical confirmation. He argues that RA is not non-empirical confirmation because the models which are used to identify robust theorems are themselves already low-level confirmed. That is, the models used in RA already have low-level confirmation and as such the resulting robust theorem is also confirmed. By low-level confirmation, Weisberg means that theorists’ confidence in models was “minimally established by demonstrating that the relevant mathematics could be deployed to make correct predictions. It may have been investigated explicitly by mathematicians.” (740)

It seems that in both cases the truth of the mathematical claim or the confirmation of the model is first necessary to support a scientific explanation or confirmed robust theorem. Pointing to a scientific explanation or robust theorem to prove the truth the mathematical claim or low-level confirmation of a model is to put the cart before the horse. Pincock and Weisberg then seem to be working with a similar structure here but at maybe opposite ends. Does this sound right,  am I confounding these two arguments, or is this just trivial?

Articles

Help Needed on Analytic/Numerical Solutions

In Uncategorized on March 8, 2010 by Leo

I need a little help clarifying what the difference is between analytic and numerical solutions as discussed in Weisberg’s “Forty Years…” article. He discusses this in talking about the limitations of brute-force models insofar as they may be incapable of either analytic solutions, numerical solutions, or both.

Numerical solutions seem to be something like being able to use the model, given some input, to achieve a numerical output. As such, it seems that the numerical solubility of a model is related to the complexity of the model and the current available computing power.

Analytic solutions seem to be some sort of “explicit description of how the parts of the model depend on one another and the magnitude of these dependencies.” (630) Is Weisberg here saying that analytic solutions are some sort of generalization of numerical data?

Regarding analytic solubility, Weisberg seems to say that there can be some models which admit of no analytical solutions regardless of simplicity. “Take a simple physical system that admits of no analytical solution, such as a three mass system with gravitation attraction between the masses… this type of system will admit of no analytic solution in closed form.” (631) Why is it the case that this model, or any other model, can never (he seems to imply) have an analytic solution? Is it some conceptual limitation characteristic of humans?

Articles

Question on Weisberg’s Conception of Explanatorily Priviledged Causal Factors

In Uncategorized on February 25, 2010 by Leo

I was wondering if someone could help me out with a question I had on Weisberg’s characterization of Minimalist Idealization (MI) which may be entirely due to my lack of knowledge on causality.

Weisberg defines MI as “the practice of constructing and studying theoretical models that include only the core causal factors which give rise to the phenomenon…. a minimalist model contains only those factors that make a difference to the occurrence and essential character of the phenomenon in question.” (642) He goes on to characterize the purpose of MI as being distinct from the purpose of Galilean Idealization (GI). While GI is done for entirely pragmatic reasons, MI is done insofar as it “aid(s) in scientific explanation” by identifying “a special set of explanatorily privileged causal factors.” (645)

What exactly is this special set of explanatorily privileged causal factors? On one level it seems pretty intuitive. The explanatorily privileged causal factors are those factors without which the phenomenon would not occur. Remove A and B will not obtain (~A ﬤ ~ B). A here could be an explanatorily privileged causal factor of phenomenon B (though I’m sure a lot more work needs to go show that A is in fact causal).

This though gets a lot more complicated when trying to determine the privileged causal factors of real world phenomenon. During our informal discussion today, Lynn had a wonderful example involving chickens. Apparently chicken eggs don’t hatch in zero gravity (who knew?!). Is gravity (to whatever degree) then an explanatorily privileged causal factor of chicken eggs hatching? Of course this could go on and on including other factors such as temperature, humidity, etc… If we include all these factors, doesn’t it seem that this model is no longer minimal? If we don’t include such factors, why is it that they are not among the privileged set? Also would you have to include negative causes as well? That is that one of the explanatorily privileged causal factors is that it is not the case that (fill in the blank).

Josh suggested (I think but correct me if I misinterpreted) that it may be the case that what causal factors are explanatorily privileged depends on the context in which we are asking the question. That is if we are concerned with chicken eggs on earth then we need not be concerned with cases of zero gravity. However if we were to raise chickens in space (a fantastic idea in my opinion), then it could be an explanatorily privileged causal factor. This though seems to suggest that MI is pragmatic but Weisberg explicitly denies this. “[U]nlike Galilean idealization, minimalist idealization is not at all pragmatic and we should not expect it to abate with the progress of science” (645)

Perhaps though the focus should be on the “explanatorily” part of explanatorily privileged causal factors. That is that MI includes only those causal factors which best explain the phenomenon. This though does seem to make MI context dependent on why we are trying to explain the phenomenon or even who the audience of the explanation is. If that is the case, then MI will not abate with the progress of science, but will vary depending on the context of explanation. This I guess could be fine? Even if this is the case though, MI does still seem a bit pragmatic, if only pedagogically pragmatic.

Articles

Philosophy of Science Seminar will be held in Strickland 429 Today

In Uncategorized on February 16, 2010 by Leo