Grue on a Tuesday

Tue 26 Jan 2010 09:47 AM

My copy of Philosophy of Science* arrived today, and I've just read Ingemar Nordin's "Technology and Goodman's Paradox." The central claim of the article is that the problem of induction is primarily an issue about whether or not to believe theories and so does not arise for reliance on techniques. Nordin ultimately suggests that - given the choice between two techniques - we should rely on the one that has the longest track record of working for us in the past.

I'm going to suggest: Either (A) Nordin's solution works for theories, too; or (B) the solution doesn't work for techniques. In either case, the problem of induction is as much a problem for technology as it is for theory.

A. Nordin's suggestion that we should rely on our most longstanding techniques is a lot like Goodman's own suggestion about predicates. Goodman suggests we generalize using 'green' rather than 'grue' because the former is entrenched. Of course, this doesn't justify our use of 'green' in any transcendent sense. If our forebears had used gruesome vocabulary, then 'grue' would be the entrenched predicate.**

But Nordin wants to say that relying on an entrenched technique is rational, whereas generalizing using an entrenched predicate is not. This requires a distinction between theories (which are confirmed) and techniques (which are relied upon). Indeed, Nordin tells us that a theory "is of course a linguistic entity that is capable of having a truth value" (p. 347). This presumes what used to be called the Received View of theories, that they are linguistic entities which have truth values. It is no longer received, not a consensus, and arguably only the minority view now. But it does yield a sharp distinction between theories (which are for believing) and techniques (which are for using).

Suppose instead that a theory is a set of resources for building models. In a paper, I call this the 'toolbox theory' concept. On this view, theories are not distinct from techniques. Instead, theories just are techniques of a particular kind. Nordin ultimately advocates something similar, writing "that from a technological point of view scientific theories should be treated as tools; as instruments for construction of techniques" [p. 352].*** If we adopt the toolbox theory concept, then any principled reason to use entrenched techniques should also be a reason to use entrenched predicates.

B. Nordin only forms grue-like alternatives to theories understood as statements. So, regarding some technique T, he opposes claims like "T works" to grue-like rivals like "T works before January 2011, but does not work afterwards." (Typing that, it makes me think that the warranty on T must run out at the end of 2010.) But we can consider gruesome techniques, too.

Suppose that I have consistently used the technique hit it with a hammer and that this has worked out for me so far. Nordin would suggest that it would be rational for me to keep hitting it with a hammer in future cases. However, how I am I supposed to know that my technique in those previous instances was to hit it with a hammer rather than to hit it with a hammer if before January 2011, but stab it with a screwdriver afterwards?

Either I have a description of my technique in mind or I do not. If I do, then we are back in with predicates. I am thinking of this as a 'hammer' rather than a 'hamdriver', and it is green vs. grue all over again. If I do not, it's not clear what distinguishes future applications of this technique from applications of different techniques. I carry on doing what I'm doing, whatever that is.

To sum up: There isn't any fault along which to separate the theoretical problem of induction from the practical problem of induction. If it's a problem, then it's a problem on both sides of the line. Theories are techniques, but techniques are also theoretical.

* v 76, n 3, July 2009. Is the journal still this far behind, or am I just getting it late?

** Note that relying on entrenched techniques leads down the same road as relying on entrenched predicates; cf. p. 353. If our forebears had long used odd techniques, then they would now be entrenched. In fact, our forebears did use lots of odd techniques. Somebody did something quirky and things went well, the quirky thing became common practice, and it became the thing that people had always done. We call these superstitions.

*** Nordin's suggestion is different than the toolbox view in two respects. First, he says it only holds "from a technological point of view." Second, he sees theories as tools for constructing techniques rather than for constructing models.


from: Greg

Tue 26 Jan 2010 01:18 PM

Hi PD --

Where can I purchase a 'hamdriver'?

re:* I don't think you're getting it late.

Your response to Nordin here sounds like Kripkenstein (adding can perhaps be thought of as a technique; and there's nothing in the world that can differentiate between adding and quadding.)

p.s. -- do _New Waves_ contributors get a copy of the new book? Or perhaps at least all of your co-authors in the volume get one?

from: Administrator (P.D. Magnus)

Tue 26 Jan 2010 08:34 PM

Greg, replying in order:

I don't know.

That's good to hear.

Yeah. I hadn't noticed the connection before, but Kripkenstein just poses the new riddle for practical life.

I think so, but I'll check.

from: P.D.

Thu 28 Jan 2010 12:11 PM

I should have realized this before, but I do know where you can buy a hamdriver - at a hardware store, although they'll insist you buy it in a two-pack with a screwmer.