Comments on: More Thoughts on Evidence

By: antonym

antonym — Fri, 04 Dec 2009 16:27:32 +0000

I know that George Smith accepts your B), Brian. To my knowledge he hasn't published on this topic directly (although I think he's planning to at some point in the future). He gave a series of lectures a few years ago, Turning Data into Evidence (scroll down for the text), although they are more about the role theory plays in marshaling evidence. If you're interested, you might want to contact him - I remember him saying that while he thought he had arrived at the conclusion himself the view seemed to be growing in popularity in phil-sci of late. (This George Smith, lest there be any confusion.)

By: fitelson

fitelson — Thu, 03 Dec 2009 03:47:36 +0000

Just to follow-up on Kent’s post, I should mention that I think the Bayesianism/Likelihoodism debate has been rather ill-framed (I’ve been arguing with Elliott about this for many years now). I wrote a paper on this a few years ago — I’d be curious to hear what you (and/or your students) think, Kent. Here’s a link:

http://fitelson.org/synthese.pdf

By: Brian Weatherson

Brian Weatherson — Wed, 02 Dec 2009 04:55:15 +0000

I hadn’t realised how much had been going on in the phil-sci literature recently. That’s really helpful. Thanks Kent!!

I should probably just read the Achinstein book myself to see this, but the bolding of ‘evidence for’ makes me wonder if the philosophers of science in question are following one of the following two strategies.

A) Take it as given what the evidence is, and get to work on the hard philosophical question of what evidence for a proposition is; or

B) Argue/presuppose that the interest in Williamson’s question “What is S’s evidence” rests on a kind of category mistake, and we should really be asking “What is S’s evidence for H”, for different hypotheses H.

Both A) and B) are consistent with focussing on when E is evidence for H, rather than on when S possesses E, but they have very different philosophical implications I think.

By: Kent Staley

Kent Staley — Wed, 02 Dec 2009 04:36:15 +0000

It’s interesting to me that there seems to be a divide between how epistemologists and philosophers of science think about evidence. There is a pretty rich literature on evidence in philosophy of science that (apart from the Bayesians who also do formal epistemology) seems pretty orthogonal to what epistemologists seem to be discussing.

One thing worth noting about the phil-sci debates is that, although Bayesian views are certainly influential, there is a proliferation of alternatives. For example, I’m teaching four different theories in a seminar on evidence next semester, of which Bayesianism is just one; the other three are likelihoods-only (e.g., Sober), error-statistics (Mayo), and Achinstein’s probabilistic-explanatory hybrid. All of these are theories that attempt to articulate the conditions under which data E constitute evidence for a hypothesis H.

But it is true that the epistemological content of some of these approaches is pretty underdeveloped, and that is unfortunate (I’m starting work to remedy this in the case of error-statistics, but it’s definitely under development).

I think Achinstein’s account perhaps deserves more attention than it gets from epistemologists in this regard. He proposes a classification of evidence concepts of varying strength and epistemic import, and he is pretty explicit about the relationship between evidence and reasons in a way that other evidence theorists typically are not.