Monday, March 19, 2007

Notes on Ludlow: Chs. 5-6

**WARNING: Technical Post**

In the beginning of Chapter 5 Ludlow says,

A first attempt at a semantical theory consistent with this [the tenseless] picture would be to give "tenseless truth conditions" for tensed sentences. That is, we want the right-hand sides to be free of A-series predicates (including 'past' and 'future' as well as temporal indexicals. (p.77)

Such a theory, as Ludlow sketches in the remainder of the chapter, would involve use of temporal language committing us to the existence of other times standing in various temporal relations (or, if we wanted to adopt more of a reductionist or relationalist picture, the existence of events standing in various temporal relations).

In the next chapter, Chapter 6, Ludlow details what he takes to be problems for the tenseless theory. The main problem is something I already addressed in my post on Chapter 3 - Ludlow thinks that the tenseless theory cannot deal with 'the indexical nature of temporal discourse'. This is just the problem with the man in the house of mirrors again. To give just one example, Ludlow claims that the following two sentences as said on March 12 express different semantical knowledge and that the tenseless theory cannot deal with this because it will have to give them the same truth conditions (in the rest of the chapter, Ludlow also, despite earlier toying with the theory, rejects token-reflexive theories for temporal language (rightly, I believe)):
(1) My fifth anniversary is (this) March 12.
(2) My fifth anniversary is today.
He also notes, with Prior, that it seems that one is not thanking goodness for any tenseless fact when one is thankful that a painful dentist visit is over with but the tenseless theory seems to require that this is what one is thankful for.

The answer here is a fairly easy one - distinguish between, on the one hand, Ludlow's "semantical" truth-conditions which are intended to mirror the speaker's perspective and way of representing things (we can call these r-mirroring truth conditions, since they are supposed to mirror our way of representing the world), and, on the other, "metaphysical" truth-conditions which are supposed to capture the metaphysical structure of the world as it matches up (or fails to do so) to our representations (we can call these m-mirroring truth conditions, since they are supposed to mirror the metaphysical structure or "joints" of reality). "'e is now' is true iff e is now" can be a correct account of the truth conditions as represented by the knower (that is, the r-mirroring truth conditions) but it can still be true that what makes 'e is now' true is the tenseless fact that e is at t (these are its m-mirroring truth-conditions). That is, it can still be true that a mental or public tokening of 'e is now' at t is true iff e is at t since at t 'e is now' and 'e is at t' express the exact same fact, just with a different representational form - the former is needed for action whereas the latter is not sufficient so that when one represents the truth conditions one needs, for action, to represent them in the latter way - in an r-mirroring rather than m-mirroring way. If they are represented as ' 'e is now' is true iff e is the time of this utterance', for instance, that will not be sufficient for action or sufficient to know that e is now since i don't know this utterance is now.

So ultimately I don't think the failure Ludlow notices in providing tenseless r-mirroring truth conditions is really relevant to whether or not we should be tenseless theorists. A tenseless theorist just isn't committed to giving r-mirroring truth conditions. Indeed, this can be seen as the characteristic difference between the Old Tenseless Theory of Russell and company and the New Tenseless Theory of Mellor and others - the Old theorists were trying to give r-mirroring truth conditions and that was shown, as Ludlow has shown once again, to be a failure. The New theorists, on the other hand, have abandoned that project as hopeless and wish instead to give us tenseless m-mirroring truth conditions while allowing that we cannot give tenseless r-mirroring truth conditions for all tensed language. I think this is where Ludlow fundamentally misunderstands what Mellor is trying to do.

This is similar to what's going on in phil mind over property dualism (the view that there are irreducibly mental properties). The phenomenal concept strategy tries to show that physical descriptions do not miss anything in the world that can be captured by phenomenal descriptions but that this is compatible with the conceptual irreducibility of the phenomenal to the physical - that is, phenomenal descriptions must be given phenomenal r-mirroring truth conditions but that's compatible with giving them physical m-mirroring truth conditions.

On the last page of the chapter, Ludlow is somewhat cryptic about why tensed truth conditions or tensed beliefs require a tensed reality:
If the world contains only B-theory resources, then precisely how do we avoid having a B-theory psychology?
The illusion of a possible way out here is fostered by thinking that there could be psychological concepts that are, as it were, disembodied - cut off from the actual world in important ways. How can a psychological property (call it foo) that bears no relation to tense in the actual world have anything to do with tense?
It is no good to say that our abstract property foo is tensed because it is grounded in our time consciousness or temporal perception. That merely keeps the question one step removed. Then we must ask what it is about time consciousness or perception that makes them tensed. Why do we call consciousness or perception tensed if it does not correspond to something tensed in the actual world?
[...]psychological states (particularly perceptual states) are individuated in part by relations to the external world. In this case, that means that if the world is not tensed then it is difficult to see how our perception of the world could be tensed. (p.96)
I'm not quite sure what the problem is here - the tenseless theorist has perfectly reasonable accounts of how our tensed psychological states hook up to the tenseless world. It is necessary for our representations in general to fed into our cognitive systems in certain forms for them to be useful to us - in order for the ordinary descriptive facts of the world to be useful for action they need to represented by us in certain special ways. Facts about time are like this too and we call our special-functioning representations tensed when they have this function with relation to time. Tense has to do with the structure of our representations, not the facts they are about. Just because our representations have particular features doesn't mean the facts they represent have to have those features. So much should be pretty darn obvious. So this plea at the end of the chapter just seems to me to be pretty lame.

Four chapter to go...

No comments: