Kant and Nomological Necessity

Here are some things I said about Kant and nomological necessity (third comment).

Fixing Possible Worlds Fictionalism: The Incompleteness Worry

There is a problem in the standard formulation of possible worlds fictionalism, which goes as follows:

(*) Possibly p iff, according to the possible worlds fiction [p is true at some possible world]

Call the possible worlds fiction $\Theta$, then we can say that possibly p iff $\Theta \vDash$ `p is true at some possible world'.  What is $\Theta$?  $\Theta$ is a set of sentences closed under deduction, but what sentences are to be included in $\Theta$?  The problem for the possible worlds fictionalist, in brief, is this: unless she can specify a possible worlds fiction that for every proposition p, $\Theta \vDash$ p or $\neg$p, then bivalence will fail.  If we endorse the biconditional (*), this bivalence will bleed over into claims regarding what is possible.

Contrast this with Lewis extreme modal realism, according to which:

(**) Possibly p iff p is true at some possible world.

One can endorse (**) without having a complete theory of which possible worlds exist, because (**) leaves it up to Nature (as it were) to decide what is possible and what is not.  So that’s the incompleteness worry in brief: without a complete, Final Theory of what is possible and what is not, $\Theta$ will not settle every fact regarding what is true at some possible world, and, via (*) will entail that bivalence fails regarding modal propositions.

I think that there is a simple-minded fix for the possible worlds fictionalist.  The problem can be circumvented if the fictionalist holds instead:

(***) according to the possible worlds fiction [possibly p iff p is true at some possible world].

Here, $\Theta$ simply is this: Possibly p iff p is true at some possible world.  Stating the fiction thus doesn’t require that we know all the modal facts in advance.  The facts about what is possible are what they are (Nature decides), and, according to the fiction, to each of these modal facts corresponds a possible world.  Another, (I think) more perspicuous, way to put this, is that we should treat the claim

(**) Possibly p iff p is true at some possible world.

as being modally adequate; i.e. that (**) gets things right with respect to the modal facts (“modal facts” are not here thought of as facts about possible worlds, but facts about what is possible, necessary, impossible, and so on).  Intuitively, a claim is modally adequate when the modal facts are the way they would have to be for the claim to be true.  (The analogy here is with the empirical adequacy of Bas van Fraassen in The Scientific Image, or the nominalistic adequacy of Mary Leng in Mathematics and Reality.  There are various ways of fleshing out nominalistic adequacy, and modal adequacy, but I won’t do so here.)

Problem: if the fiction operator is placed at the beginning of the sentence, if we treat (**) as merely modally adequate, how can we ever make use of possible world fictions to come to know modal truths?  Won’t it be the case that we will only be able to make claims about what is possible, impossible or necessary according to the possible worlds fiction?  To see that this is not the case, recall that a claim is modally adequate just in case it gets things right regarding the modal facts.  As such, claims that pertain only to the modal facts which are modally adequate are, by definition, true simpliciter.  Derivations can be carried out which quantify over possible worlds.   From modally adequate premises regarding possible worlds, modally adequate conclusions regarding possible worlds can be obtained.  We can then make use of the biconditional (**) to “translate” these into modally adequate modal claims.  But, since modally adequate modal claims are true simpliciter, we can legitimately infer the truth (simpliciter) of modal claims by making use of merely modally adequate claims quantifying over possible worlds.  The trick is to treat (**) as merely modally adequate rather than true simpliciter.  Both fictionalism regarding possible worlds, and bivalence are retained.

Safety, Sensitivity and the Value of Knowledge

Epistemologists who wish to provide a modal analysis of knowledge are divided over whether the safety or the sensitivity condition offers a correct necessary condition for knowledge.  The two are usually parsed in (something like) the following way:

Safety: S’s belief p is safe iff in nearly all (if not all) nearby possible worlds w in which S forms a belief p using the same belief-forming methods as the actual world, p is true.

Sensitivity:  S’s belief p is sensitive iff in the closest possible world in which S forms her belief using the same belief-forming methods as the actual world and in which p is false, S does not believe p.

Sosa suggested the following scenario, which has been influential in encouraging philosophers to favour safety over sensitivity:

On my way to the elevator I release a trash bag down the chute from my high rise condo.  Presumably I know my bag will soon be in the basement. But what if, having been released, it still (incredibly) were not to arrive there? That presumably would be because it had been snagged somehow in the chute on the way down (an incredibly rare occurrence), or some such happenstance. But none such could affect my predictive belief as I release it, so I would still predict that the bag would soon arrive in the basement. My belief seems not to be sensitive, therefore, but constitutes knowledge anyhow, and can correctly be said to do so. [‘How to Defeat Opposition to Moore’: 145-6]

Now, I’m not convinced that the condo owner really has knowledge in this case—as opposed to a true, justified belief, or knowledge of some closely related proposition, such as that it is highly probable that the bag is in the basement—and I also think that examples with the same structure as Sosa’s offer some evidence against the safety condition and in favour of sensitivity.

For instance, I once went to meet my supervisor on the fifth floor of our building, only to discover that his office was not there: he had moved to the sixth floor.  Two things strike me about this.  Firstly, it seems to me perfectly reasonable to hold that I didn’t have knowledge that he was on the fifth floor, even when this was true and I was justified (and safe) in believing it.  I was not properly connected to the facts: when the justified, true (and safe) belief became a justified, false belief, I was oblivious to the change.  Secondly, and relatedly, it is often thought that we value knowledge resides (at least in part) to its connection to felicitous action.  A mere true belief is, all things being equal, less valuable than knowledge because the vagaries of the world ensure that it has a tendency to turn into a false belief.  Known propositions are the sort that allow us to successfully navigate our environment, and false beliefs will (in ordinary circumstances) lead us to behave infelicitously (e.g. by going to the fifth rather than the sixth floor).  The thought here is that there are many scenarios akin to the one above, and, hence, sensitivity seems to be a necessary condition for the sort of belief that allows a person to successfully navigate her environment.

Nazi Philosophers

This article appeared in the Telegraph a few days ago chronicling the rise of Nazi philosophers in Hitler's Germany:

‘[Most academics in Germany] did not merely reconcile themselves to Hitler. They enthusiastically espoused Nazi ideology, and came up with all sorts of elaborate reasons to justify the purging of Jews, the persecution of dissidents, and the conquest and oppression of other nations. They went out of their way to flaunt their loyalty to the Nazi cause.’

The diagnosis of why this happened that caught my eye:

‘Their deluded enthusiasm for the debased ideology of the Nazis is an instance of the fact that people who spend their lives debating abstract issues can become so distanced from the quotidian world that they can no longer see the obvious.’

This is a thought that I’m not wholly hostile to (although it's not clear it explains the uptake of Nazism amongst academics: plenty of people who occupied the "quotidian world" were Nazis too), but Palmer continues:

‘Philosophers are particularly vulnerable to this form of idiocy, because there is so little content to their subject.  It does not consist in the discovery of new facts, and philosophical theories are only seldom decisively refuted by anything.  Fashion is often the most important factor in explaining which doctrines come to be accepted by any group of academic philosophers.’

I think there is a more charitable explanation to be had.  Philosophy involves teasing out the consequences of various commitments.  This involves three responsibilities, one critical, one ampliative and one justificatory. [I'm drawing on Brandom's Reason in Philosophy here.]  The critical responsibility is to rectify mutually incompatible commitments, it is to ensure that one's system of beliefs is consistent.  If one maintains P, $\neg$Q and P $\rightarrow$ Q, then at least one of these commitments must be jettisoned.  The ampliative responsibility is to become aware of the material consequences of one's current commitments.  Acknowledged commitments give rise to further commitments that one may not yet be aware of.  The responsibility to make oneself aware of these further commitments and to integrate them appropriately into the whole is a responsibility that aims at completeness.  Whereas the ampliative responsibility looks inferentially downstream, the justificatory responsibility looks inferentially upstream.  Agents are responsible for offering reasons for their commitments, by claiming commitments that entitle them to their current commitments.  The justificatory responsibility is directed at ensuring that one's network of commitments is warranted.  Philosophy is aimed at acquiring a certain kind of understanding, an integration of our beliefs into a coherent whole.  Unearthing our inferential commitments however can only take us so far; it can tell us that P, $\neg$Q and P $\rightarrow$ Q are not compossible, but it does not tell us what thereby to so; whether to reject our belief P, our belief $\neg$Q, or whether to reconsider the conditional itself.  As the saying goes, one man’s modus ponens is another man’s modus tollens.

This goes some way to explaining why philosophers aren’t inoculated from evil political ideologies.  An ability to reason is not, by itself, sufficient to steer away from such things.  In fact, an ability to reason can aid dogmatism, as it makes it easier to defend a view, any view, from counterarguments.  The lesson I think ought to be drawn from the sad prevalence of Nazi philosophers isn’t that philosophy “lacks content” (however that view is parsed), but that rational nous alone isn’t enough to get at the truth; we also require the intellectual virtues of open-mindedness, independence of thought, intellectual honesty and humility, and self-awareness.  Reason, in this sense, is rather like courage: whether it is used for good or ill depends on the other character traits of those who employ it.

An Argument for Libertarian Free Will From Cognition

Here's an argument that human persons have libertarian free will:

1. Cognition is (distinguished as) that which is properly subject to certain kinds of normative assessment.  (The "mark of the mental" is that it is subject to certain kinds of normative assessment.)
2. If cognizers did not have libertarian free will then cognition would not be properly subject to those kinds of normative assessment. 
3. Cognizers have libertarian free will.
4. Human persons are cognizers.
5. Therefore, human persons have libertarian free will.

The idea behind the 1 is that persons are responsible for their beliefs.  If someone believes that P, that if P then Q, and that not Q, then that person has transgressed in some sense.  Cognition is bound by rules, not in a nomic sense (these rules can be violated), but in a normative sense (one ought not to violate these rules).  Sapients are distinguished from non-sapients in precisely this way: one ought not to criticize a system on the grounds that its entropy is increasing, but one can criticize a person on the grounds that his beliefs are inconsistent.

The motivation for 2 runs along the same lines that are usually given for holding that moral responsibility requires libertarian free will: namely that if determinism is true then one's acts are consequences of laws of nature and past events, but (i) we are not responsible for what laws of nature and past events obtain, and hence (ii) we are not responsible for the consequences of what laws of nature and past events obtain (including the subset of those consequences that contains our actions).

Van Inwagen famously argues for libertarian free will on the grounds that we have moral responsibilities, but it seems to me that the argument from cognition has a dialectical advantage over the moral one.  Philosophers are largely willing to reject the existence of moral truths if they take this to be incompatible with their metaphysical commitments.  I doubt that philosophers generally would be as willing to give up cognition on those grounds.

I take it that 2 is the controversial premise here, but it seems prima facie plausible to me.

Languages Don't Exist

Here's an argument that we ought not to postulate the existence of languages.  The argument isn't formally valid, but it could easily be made formally valid, and I think that it would then be sound:

1. What a philosophy of language needs to account for is communication.  Once we have explained communication there are no further facts about language that need to be explained.
2. In order to account for both communication failure (the many occasions in which we talk past each other) and special cases of communicative success (when the meaning of our utterance is more than, less than, or has no overlap with what we intend to convey—as in, e.g., certain cases of definite description use, and metaphor), we must reject decoding accounts of communication and adopt relevance accounts of communication.
3. Relevance accounts of communication explain communication in terms of ampliative inferences as to a speaker’s communicative intentions.
4. An account of ampliative inference as to a speaker’s communicative intentions need not involve languages, only particular facts about individual speakers.
5. We can explain all the facts about language-use without positing the existence of languages.
6. (In practicing philosophy of language ) we should only postulate those entities required to explain the facts about language.
7. Hence, we should not postulate the existence of languages.

Perhaps some doubt could be cast on 1, but I'm sceptical that any other facts a philosophy of language ought to account for would require postulating the existence of languages.

One last post on understanding

1. Both intuitionistic logic and classical logic are understood.
2. It is not the case that both intuitionistic logic and classical logic are sound.
3. Hence, there is something that is understood which is not true.