Chapter 2: Realism, Reference and Possible Worlds - Section I.
I gotta say it straight out-Professor Norris' style is not accessible to the undergrad. This is not a fun type of learning-it becomes fun when I finally figure it out-but it would've been way funner, and from the start, if it had been written at my reading level. Here's what I "could" grasp (or think I did grasp, anyway) from the first section--
This section was mostly about Saul Kripke's reference-fixing (naming), in comparison with Frege and Russell's descriptivist theory (emphasis on Frege). There's background involving "problems bequeathed by Kant's great attempt-in the Critique of Pure Reason-to delimit the sphere of cognitive understanding (where sensuous intuitions must be 'brought under' adequate concepts) from that of metaphysics where reason has a license to raise such speculative issues but only on condition that it not lay claim to any kind of determinate knowledge." Whatever THAT means. There is talk of "redrawing the Kantian line" … of taking "full stock of the 'linguistic turn'" -whatever that means-of Kripke and Putnam (apparently a guy named Hilary-sorry, man) putting the case "for a strong causal-realist and objectivist approach to epistemological issues". Causal-realism is defined in section II. Here's what comes up in section I--
So basically the two theories compared are descriptivism (Frege) and naming (Kripke). You've got the name of something (gold), and then you've got a description of something (formerly: "yellow, ductile metal that dissolves in weak nitric acid"; now: "metallic element with atomic number 79"). The name, and the description, are called "referents".
Descriptivism (Frege) says that names do not always refer to the same thing if we attach conflicting descriptions to the same name, and that descriptions are more important (the "former" description of "gold" is not the same "gold" as the "now" description of "gold"-it's like they should be given different names…but consider the underlying reasoning of that). It gets weirder. "Strong descriptivists or paradigm-relativists like Thomas Kuhn [conclude] that shifts in the range of identifying criteria from one theory or classificatory system to the next can at times be so drastic as to break the referential chain of transmission." This is called "radical 'incommensurability' between paradigms". This 'desperate position' is adopted because of Frege's "sense determines reference" and an idea Frege rejected: "the sense of any given term can only be specified in relation to the entire language, discourse or received body of knowledge within which it plays a role." So, according to this position, the two things don't just need different names now-they inhabit different worlds (harkens back to Quine's "web of belief"). There is therefore no accounting for scientific progress, since you're stuck in the world-web of your preferred description.
Naming (Kripke) would say that descriptions of a thing may change and so do not always refer to what they are describing-which has a name which stays the same and refers to what is being described even if the description changes (the two descriptions of gold are describing one thing named "gold"). Kripke is saying (1) the reference of the name "gold" (to that thing to which the name "gold" refers) is "necessarily" fixed at its conception (in the mind) and (2) is preserved throughout "every shift in its associated range of descriptive criteria". If that word "necessarily" trips you up-that is explained next:
The explanation of "necessarily" has to do with modal logic - "the branch of logic having to do with possibility and necessity". Kripke "makes a case for the existence of a posteriori necessary truths…which are neither analytic, i.e., true-by-definition, nor a priori, that is to say, self-evident to reason, but which nonetheless hold necessarily in any world where their referents exist or once existed." Did that clear it up for you? Me, neither. Not even when Norris used examples. [See link in reply below on a priori / a posteriori, the water example.] Anyway, somehow that means thatnames are "truth-tracking"-they stick even when descriptions change ("sensitive to future discovery")-name-reference transcends the 'paradigm-shift'. This is called reference-fixing.
The rest of the section I couldn't quite make out, unless the example I'm about to provide (not provided by Norris) explains it well: when it comes to language translation, different languages all have different names (at least one per language) for the same thing (assuming they all have a name for that thing), so all those names refer to that one thing. How else do we know all the names refer to that one thing, but that the names all have similar descriptions? Somehow, according to some philosophers, the Kripkean approach "allows-indeed requires-some additional descriptivist component."
And I wanted to re-paste what I wrote in section IV of the Introduction:
"I think a descriptivist account says that features are not essential, that they fail to refer, that imputed properties before discovery (about some object), and imputed properties after discovery (about that object), will not be referring to the same object (if so-then how do you know what object you made a discovery about?)."
[Side-question, prob'ly stupid: Does all this discussion about referents assume all names (or even descriptions, for the descriptivist) refer to something that actually exists? For example-what about names like "unicorn" (or descriptions of them)? Probably it would only count as referring to an idea (based on lack of evidence for their corresponding to reality)?]
A helpful reply from Professor Norris to my side-question, which also explains Frege's "sense determines reference" which I didn't really get until now:
Yes, the normal assumption is that the objects or events referred to (described, specified, picked out, etc.) really do or did once exist - as per Frege's distinction between 'sense' and 'reference', where 'sense' is the range of properties or attributes that people have in mind when they talk about something and 'reference' is what the description picks out when and if it 'goes through' in the normal way. So allusions to fictive characters and events (or to imaginary objects like unicorns) have sense but not reference.
http://en.wikipedia.org/wiki/Linguistic_turn There's other turns, too.
I thank Professor Norris for the above explanation, as it was absolutely essential that I understand Frege's "sense determines essence" in order to go forward.This is cool: http://en.wikipedia.org/wiki/A_priori_and_a_posteriori#Relation_to_the_necessary.2Fcontingent
http://en.wikipedia.org/wiki/Semiotics ... think it might have something to do with this. Fascinating.