Tuesday, March 20, 2007

Notes on Ludlow: Chs. 7-9

**WARNING: Technical Post**

In Chapter 7, Ludlow begins to construct an alternative, tensed semantics. Parts of this have a strongly antirealist, idealist, or verificationist sort of feel about them. In fact, Ludlow seems to agree with uberantirealist Michael Dummet, stating, 'As Dummet (1969) has argued,a semantic theory that accounts for an agent's semantic knowledge must show how portions of the language are learned from the evidence available to the language learner' (p.99). I'm not sure that this is really correct as it pushes us towards an untenable kind of antirealism about practically everything. And I'm not sure whether Ludlow wants to be committed to such a view. Then again, he seems to flirt with idealism throughout the book, so maybe I shouldn't be so surprised. To continue the quote,

But now consider how we learn to use past-tense expressions such as (4).
Dinosaurs roamed the Earth.
We do not evaluate this sentence by imagining some time earlier than now and determining whether at that time (4) is true. Rather, we evaluate (4) by right now conducting the sort of investigation that is appropriate for past-tense statements like (4). (For example, we might study fossil records.) Likewise for any past-tense statement. We have certain procedures for determining whether a past-tense proposition is true, and these procedures do not involve the evaluation of a proposition at some time past; rather, we simply evaluate the proposition in a particular way - a way which is independent of how we evaluate present-tense and future-tense propositions.
Consider the future-tense proposition (5).
The economy will recover in the third quarter.
Clearly we do not evaluate such a proposition by picking some time in the third quarter and determining whether it is true at that time that the economy is recovering. Rather, we evaluate it by studying the currently available economic data. Crucially, our evaluation of (5) can proceed without our ever attending to a corresponding present-tense proposition at some future time index.

It's not quite clear to me how any of this is relevant to the debate over tense. After all, the tenseless theorist can simply grant that Ludlow is correct that we look at present evidence to determine the truth of past or future tense statements. The mistake is to infer from this that when we determine the truth or falsity of past or future statements we are not thereby determining whether a certain tenseless fact holds. Using present evidence and not attending de dicto to any present-tense proposition at some future time index is perfectly compatible with this. The only way one could think otherwise would be to assume that tensed r-mirroring truth-conditions must also be m-mirroring truth-conditions. And that, as I've been arguing is clearly a mistake. After all, the same sorts of things Ludlow says about tensed statements could be said about first-person or 'here' sentences as well.

But he continues,

If this picture of the underlying robust theory is correct, then it immediately leads to a second advantage for the A-theory [tensed] proposal under discussion - in fact, a striking epistemological advantage. The B-theorist is in the untenable position of asserting that there is actually reference to past and future times and/or events. However, this flies in the face of everything we know about reference. We are in neither a perceptual relation nor a causal relation with future events, and our causal connection with most past events is tenuous at best. In regard to times, the idea that there could be reference to such abstract objects surely requires major adjustments to current epistemological thinking.

This argument or set of arguments here seems to be a non-starter. I'm not sure how anything Ludlow says makes reference to or quantification over future or past events or times at all problematic. That our causal relation to past things is tenuous seems irrelevant since all that is needed for causal theories of reference is causation - not "super duper not-so-tenuous causation". And if we have a causal theory of reference, then it is reference to present things that is problematic since causation is a cross-temporal relation. That we do not have any causal relation with future things is, I think, not as clear as Ludlow seems to think, but let's give him that for the moment (I tend to think it's false, actually). But quantification or reference do not necessarily require causal relations - one can fix the reference of a name, for instance, by introducing it via an identifying description without having any clear causal contact whatsoever with the object satisfying the description. And quantification over certain entities does not seem to require being causally related to all of them and there's no clear reason why we would need to be. In addition, on most theories of time, times are not abstract but rather concrete objects. In any case, they are treated the same sort of way as places or parts of space. We seem to be able to refer to or quantify over space or regions thereof, so why not times? There seems to be no difference here. All of Ludlow's criticisms here could just as well be thrown against the view that other persons or object outside of myself exist and that we quantify or refer to them. If Ludlow were correct, his views would be pushing us towards a dangerous ontological solipsism where only I exist or an epistemic or semantic solipsism where only I can be referred to or quantified over by myself.

Ludlow ultimately comes to think that his semantics leaves presentism as one of the only plausible, consistent accounts of time. But if we accept presentism for time based on the problems outlined in the book, it seems that similar problems for first-person sentences or 'here' sentences are going to force us into the ontological solipsism mentioned above. After all, if presentism is a main way to get out of McTaggart's Paradox for time, solipsism will be an analogous way to get out similar paradoxes for persons.

Indeed, Ludlow's tensed semantics could be transformed into an analogous first person or 'here' semantics. Ludlow claims in Chapter 8, for instance, that apparent reference to times like 'June 24, 1972' can be paraphrased away as 'when standard calendars read "June 24, 1972"' and that normal tensed sentences will actually be decomposed as complex sentences composed of two tensed sentences joined by 'when', 'after' or 'before'. But we can do the same sorts of things with apparent reference to places and decompose 'here' sentences as complex sentences composed of two 'here' sentences joined by 'where', etc. So 'Paris' becomes something like 'where standard tracking systems read "Paris"'. If we do want reference to times, we can build times up as collections of when-clauses, according to Ludlow. But then if we want reference to places, we can build them up as collections of where-clauses. Perhaps we can do this sort of thing with persons as well - only I exist, but I can refer to other persons as collections of who-clauses (?).

At the end of Chapter 8, Ludlow shows that his theory can apparently get him out of one formulation of McTaggart's Paradox. But it's far from clear that it can escape a reformulation to match Ludlow's theory. Heather Dyke's formulation, suitably adjusted to face Ludlow, seems, for instance, like it would cause Ludlow particular trouble.

Chapter 9 consists in listing some psychological considerations that may or may not help the tensed theorist. I think they do not - the tenseless theorist should be at ease with all the data discussed. In fact, that's just the sort of data one would expect if the New Tenseless Theory were true - people think tensedly. In fact, some have argued that the data actually favors the tenseless theory. In addition, not all of the discussion is clear or very clearly well-motivated. Some of the discussion of and quotes from Merleau-Ponty, for instance, is metaphorical and opaque at best and of unclear relevance to the topic or the use Ludlow seems to want to put it to. So I think chapter 9 is inconclusive at best.
The last-ish notes are soon to com.

No comments: