Wolfgang Schwarz

TPG Fix

Since it doesn't look I will be able to finish the new version of my Tree Proof Generator anytime soon, I've now added a rough fix for the problem with unrecognized old terms.

Break

Sorry for the recent lack of postings. I'm taking a break from typing to rest my wrists.

Backups

Not only my hands, but also my computers are now threatening to fall apart. While I unfortunately forgot to make backups of my hands, I've just copied all important data from my computers to the server. Most of it is not worth letting the googlebot know, a possible exception being two German scripts (1, 2) I wrote last year about recursiveness, representability, and Gödel's first incompleteness theorem, largely based on chapters 14 and 15 of Computability and Logic, 3rd ed. I've also uploaded some of the songs I made during the past 10 years to this directory, though as with all bad music, it's much more fun creating it than listening to it.

Fictionalism's Ontological Commitment

Fictionalism about a certain discourse is the view that statements belonging to this discourse are to be interpreted like statements in fictional discourse.

Now as Brian has observed, on the common account of fictional discourse, "Fictional(Fa)" implies "(Ex)Fictional(Fx)" (even though it normally doesn't imply "(Ex)Fx"). So one might think that on the common account, fictionalism can't do with fewer entities than realism, even though it can do with different entities. However, the common account is not committed to "Fictional(a != b)" implying "(Ex)(Ey)(x != y)". After all, it usually allows for "(Ex)(Fictional(Fx) and Fictional (not-Fx))", so why not allow for "(Ex)(Fictional(x != b) and Fictional(x = b))"? So maybe one could endorse fictionalism about mathematics and the common account of fictional discourse without being committed to an infinity of entities by claiming that all the "numbers" talked about in mathematics are in fact identical.

Realism, Reductionism, Determinatism

Allan Hazlett, in his Against Fictionalism, says that if numbers exist then "there is a fact of the matter about which sets numbers are", even if we can't find it out. I don't think realism and reductionsism about numbers implies this kind of determinatism. (Sorry, "determinism" was already taken.)

The point is general. I believe in psychological states, and I believe that psychological states are really just neurophysiological states. But I don't believe that it is possible to isolate a single brain state that realises the pain role, or the believes-that-the-meeting-starts-at-noon role. The problem is that folk psychology is probably far too unspecific to have a unique realisation. (This is not the problem of multiple realisability, or not quite. Multiple realisability is usually taken to be the problem that pain is or might be differently realised in different individuals. It would be interesting to know more about the relation between the two problems.)

Similarly, I believe in mountains, and I believe that mountains are really just mereological sums of rocks, stones, sand, etc. But I don't believe that it is possible to isolate a single sum of rocks etc. that is (determinately) Mt. Everest.

Vague Objects, Strange Properties

Assume some sentence "Fa" is neither determinately true nor determinately false. This might be due to the fact that

1) It is somewhat indeterminate exactly which object "a" denotes.

or

2) It is somewhat indeterminate exactly which property or condition "F" expresses.

If neither (1) nor (2), then "a" determinately denotes a certain object A and "F" determinately expresses a certain condition F. So whence the indeterminacy? Maybe

In Defense of the Impossibility Hypothesis

My wrists still don't feel quite fine, in particular after writing such a long piece as this one. So this will probably be the last entry for another couple of days.

I want to defend the Impossibility Hypothesis about Imaginative Resistance. The hypothesis is that when we find ourselves unwilling to accept that some statement explicitly made in a fiction is true in the fiction, this is (always) because what the statement says is in some sense conceptually impossible.

Visitors

I would like to know what is being discussed in some non-public forum on ubbforums.ubi.com, from where quite a lot of visitors have arrived within the past weeks. (From a brief glance at these forums, I don't even have a clue what they might be about.) So if you are one of these visitors, would you drop me a line and tell me?

For some reason, the two Gods puzzle also seems to have attracted some attention recently. Today, a clever reader called Ian Stern even found a new solution which, though not truthfunctional, is much more natural than my original solution: 'Would God A say that "qwer" means "yes"?'

Counterfactuals and Games of Make-Believe

In chapter 10 of The Varieties of Reference, Gareth Evans endorses a counterfactual analysis of truth in games of make-believe: When children play the mud pie game, an utterance of "Harry placed the pie in the oven" is true (in the game) iff (roughly) it would be true given that these globs of mud were pies and this metal object were an oven.

He then notices that this is a problem for the possible worlds analysis of counterfactuals because the relevant counterfactuals seem to have impossible antecedents: "there simply are no possible worlds in which these mud pats are pies" (p.355).

Semantic Properties and Bearerless Names

Linguistic expressions have all kinds of properties. In other words, they can be alike in all kinds of ways. For example, two sentences (of a particular language) can be alike in that

1. they have the same truth value
2. they attribute the same property to the same object
3. they are necessarily equivalent
4. they are a priori equivalent
5. they are such that noone who understands them could regard one as false and the other as true
6. they are cognitively processed in the same way in all speakers of the language
7. they invoke the same mental images in all speakers
8. they invoke the same mental images in some particular speaker
9. they have the same use in the community
10. they are verified by the same observations
11. they are constructed in the same way out of constituents that are alike in one way or another

and so on. All these properties are, I believe, worth investigating into, and all of them might be called "semantic".