philosopher makes mistake

August 31, 2007

In “How to Define Theoretical Terms” (1970), David Lewis says the following. Take a theory T that introduced a new term ‘t’. Replace ‘t’ in T with an appropriate variable to form an open sentence R`. Lewis now claims that ‘t’ is correctly defined as follow:

t = the unique x such that R`

Note the uniqueness requirement. If there are multiple realizations of R` (that is, variable assignments that satisfy R`) differing in what they assign to x, then ‘t’ is denotationless. Van Fraassen (1997) argues that, provided only that T is consistent and has an infinite model, such will always be the case. Read the rest of this entry »

the illusion of superficially contingent a priori knowledge

August 30, 2007

I suppose the fact that I think it is easier to get examples of deeply contingent a priori knowledge than of superficially contingent a priori knowledge puts me in the minority. Anyway, Hawthorne (in “Deeply Contingent A Priori Knowledge”) cites Evans’ Julius case as a paradigm example of superficially contingent a priori knowledge:

(E) ∃!x(x invented the zip) → Julius invented the zip

(E) is contingent, I presume, because there are worlds in which someone uniquely invented the zip, but it wasn’t Julius. It is, according to Hawthorne, superficially contingent because the name ‘Julius’ has been stipulated to designate the inventor of the zip, so simply understanding the meaning of (E) puts one in a position to recognize that the actual world verifies (E).

The problem is that there are two readings of (E), one on which ‘Julius’ takes narrow scope with respect to the antecedent, and one on which ‘Julius’ takes wide scope over the whole conditional. I contend that only the narrow scope reading is knowable a priori, but the narrow scope reading is necessary, not contingent.

Read the rest of this entry »

the (x) habits of highly productive philosophers…

August 17, 2007

so i’m not really sure this is a methodology question, but…

i’ve been suffering from some serious jetlag, which has got me waking up at 3am. i’ve been finding, though, that 5am to 7am is a fantastic time for me to write. however, for various reasons, i suspect this schedule will prove untenable in the long run.

this got me wondering about other people’s writing habits (both good and bad), and, more generally, any tips or advice other people might have about how to increase one’s productivity, get more writing done and increase the quality of said writing, spend less time writing random blog posts when one should be finishing papers, etc etc.

example: i’m pretty good at starting papers, but i suck at finishing them. as a result i have like ten drafts of papers that are about 70% done. but that always seems to be the point at which i decide that the original idea is junk, or untenable, or uninteresting. how can i become more of a ‘closer’?

in sum: what are your best (and maybe worst) work habits? how can a grad student, who is typically balancing teaching and coursework and more personal projects, maximize his or her productivity? what sorts of habits (besides the obvious: drinking) undermine one’s productivity?

input is greatly appreciated by me, and, i suspect, other readers of this blog.

Plantinga on Whether Belief that God Exists is Properly Basic

August 13, 2007

Alvin Plantinga argues for the following two claims (Warranted Christian Belief, 186-190):

(1) If God exists, then basic belief that God exists is probably properly basic.

(2) If God does not exists, then basic belief that God exists is probably not properly basic.

Let’s assume that he’s right about (1) and (2). However, from (1) and (2) Plantinga infers that

(3) To answer the question of whether basic belief that God exists is properly basic, we must answer the question of whether God exists.

Here is what Plantinga says when he makes the inference:

And this dependence of the question of warrant or rationality on the truth or falsehood of theism [the dependence stated in 1 and 2] leads to a very interesting conclusion. If the warrant enjoyed by belief in God is related in this way to the truth of that belief, then the question whether theistic belief has warrant is not, after all, independent of the question whether theistic belief is true. So the de jure question we have finally found [of whether basic belief that God exists is properly basic] is not, after all, really independent of the de facto question [of whether God exists]; to answer the former we must answer the latter. (191, bold added)

There seem to be two importantly different readings of (3)—and, similarly, the bolded line above. On the first reading, (3) is unimportant. On the second, the inference from (1) and (2) to (3) is fallacious. Read the rest of this entry »

personal and doxastic justification

August 3, 2007

In their “The Basic Notion of Justification” (Phil. Studies, 1989), Kvanvig and Menzel incredibly attempt to defend the equivalence (J) by appeal to the lambda calculus:

(P) S is justified in believing p

(D) S’s belief that p is justified

(J) (P) ≡ (D)

Kent Bach and my friend Clayton hold that (P) involves the notion of personal justification — roughly, the kind of justification that is a property of responsible cognitive agents — while (D) involves the notion of doxastic justification — the kind of justification that is a property of justified beliefs. According to them, these are distinct notions and so (J) is a false equivalence; there are cases where an instance of (D) is true of some person, but the relevant instance of (P) is not, and vice versa.

Kvanvig and Menzel give a counterargument which I think is wrong. They begin by assuming that the logical form of (D) is as follows:

Read the rest of this entry »