Friday, July 10, 2009

Truth and explanation

As some of my previous posts note, one of the contemporary debates over truth is whether truth can be explanatory. If so, then, it is argued, it is a bona fide property, a relational one according to most proponents of this. The form of arguments offered by folks like Kitcher is something like this: Success at a certain activity is best explained by the hypothesis that practitioners have true beliefs about an area of the practice; hence, having one's beliefs be true is an explanatory property. This is an argument that concludes to the property-hood of truth from truth entering into an explanans.

It seems that it might also be possible to go the other way: it seems one can conclude to the property-hood of truth from truth's entering into an explanandum. For instance: Why is it that most of our short-term predictive beliefs are true? Surely it is plausible that we can give a natural selection (either of the genetic sort, connected with belief-forming faculties, or of the mimetic sort, connected directly with particular beliefs or more general ideologies) explanation of the truth of these beliefs. Moreover, the explanation is causal in nature. Now, it is plausible that if we can give a causal explanation of the obtaining of some feature, that feature had better be a bona fide property in a broad (i.e., abundant) snese.

I don't know if this is an independent argument for the propertyhood of truth, though. For our reason to think that a natural selection explanation of the truth of these beliefs is possible is that it is plausible that the truth of these beliefs leads to (biologically or culturally) reproductive success. And this "leads to" is itself explanatory. So it seems that the status of truth as entering into explananda in the selective way is dependent on the status of truth as entering on the explanans side of explanations of fitness.

This leads to an interesting question. The person who believes in the closedness of the natural (in particular, any naturalist) is committed to the correctness in our world of the inference:

  1. F is natural; E's occurrence explains F's occurrence; therefore, E is natural.
Should she also accept the following formally similar inference?
  1. E is natural; E's occurrence explains F's occurrence; therefore, F is natural.


Peter Youngblood said...


Concerning the question about the naturalist, wouldn't she have to accept any occurring event what-so-ever as natural? I have a very difficult time separating naturalism from determinism, but some very intelligent people seem to think they can do so. What do you think?

Alexander R Pruss said...

Maybe. But some more moderate naturalists might allow that for all we know there explanatorily irrelevant non-natural facts. After all, how would we know there weren't?

Peter Youngblood said...

I suppose I'm just unsure what the naturalist could possibly mean, considering her worldview, by the term "non-natural fact". If nature is all that exists, wouldn't the predicate "non-natural" be tantamount to "non-existent"? It would surely be silly to allow for there be be non-existent facts.

Perhaps I am misunderstanding.