Comments on: Chmess and twaddle

By: dsquared

dsquared — Thu, 01 Jul 2004 12:29:32 +0000

with a short German “a” and a steely gaze.

By: Matt Weiner

Matt Weiner — Tue, 29 Jun 2004 22:44:06 +0000

Where I’m from “twat” rhymes with “hot”, but “twater” — alike “water” — rhymes with “caught her” (rather than “got her”). Same with me, except that “caught her” and “got her” may also rhyme, especially if you say them fast.
Next question: How should you pronounce “Kant”?

By: Anders Weinstein

Anders Weinstein — Tue, 29 Jun 2004 17:00:29 +0000

I thought Land’s experiments were taken by him to support the “retinex theory”, according to which the stimulus for color is reflectance (actually, a triplet of reflectances). The point of Land’s experiments is that the stimulus for color is not intensity of light of various wavelengths alone. But the retinex theory does nevertheless give us some fairly natural physical property, one which is in fact more invariant under changing illumination, as the basis for color experience. In artificially contrived situations, illusions can of course result if the way the visual system (in effect) estimates reflectances in the normal environment under which it evolved is no longer reliable under these circumstances. I haven’t read Hardin myself, and I have also heard that the neat retinex theory itself has its problems in turn. But Land’s reflectance-based theory has been taken to support a physicalist theory of color (e.g. by Paul Churchland in, I think, Scientific Realism and the Plasticity of Mind).

By: intrigued guest

intrigued guest — Mon, 28 Jun 2004 23:40:01 +0000

O.K. – thanks Matt. So the moral is: don’t talk about surface spectral reflectance and wavelengths without reading up on the Land experiments first. Got it!

By: Matt McGrattan

Matt McGrattan — Mon, 28 Jun 2004 19:46:37 +0000

Well, it might be worth while to take a look at Land’s work. I believe the Hardin book ‘Color for Philosophers’ has a summary. The original papers are in Scientific American … I don’t have the exact citations to hand. Basically, Land carried out a range of experiments which taken together show that colour has little to do with surface spectral reflectance and is only indirectly connected to the wave length of light. [I’m probably over-simplifying here] For example, he showed how one could project an image using nothing but red and white light and yet create the impression in viewers of a full colour image. He also carried out a range of experiments using so-called colour ‘Mondrians’ in which he was able to take patches of colour and manipulate them so that a single patch’s surface spectral reflectance remains constant and yet its perceived colour alters. There’s a number of other experiments all of which taken together suggest that perceived colour is the product of a complex interplay of wavelengths across the visual field where the relative rather than absolute lengths of the wavelengths give rise to perceived colour variation. I’ve lost track of how often people appeal to things like wavelengths of light, surface spectral reflectance and so on when talking about colour. Of course they are usually hedged by ceteris paribus clauses and references to ‘standard conditions’ and so on. But they still seem then to proceed more or less as if colour was nothing more than surface spectral reflectance. [And I’m not just talking about objectivists about colour here… dispositionalists also often proceed as if the ground of the disposition was straightforwardly something like surface spectral reflectance.] Of course there’s loads of philosophical work on colour where the Land experiments aren’t strictly relevant and lots of other work that DOES take that kind of data into account. But I do often attend seminar presentations or other talks which do proceed in ignorance of Land’s work when it is relevant. [Sorry for the slightly rambling nature of this reply….]

By: intrigued guest

intrigued guest — Mon, 28 Jun 2004 02:40:29 +0000

‘Work on perception, and on colour in particular, often seems to be woefully under-informed about the science of colour perception. I’ve lost track of how often I hear people confidently pontificating away and making claims that are straightforwardly contradicted by things like Land’s experiments on vision from the 50s and 60s.’ Sorry to backtrack, but I think I might be exactly the sort of person that Matt has in mind here (I certainly know nothing of Land’s experiments, and I’m trying to write a thesis on colour perception). Could I therefore ask Matt to say, in a nutshell, what sort of pontifications he has in mind?

By: foxforce5

foxforce5 — Sun, 27 Jun 2004 01:53:58 +0000

Where I’m from “twat” rhymes with “hot”, but “twater”—alike “water”—rhymes with “caught her” (rather than “got her”).

By: Matt McGrattan

Matt McGrattan — Sat, 26 Jun 2004 23:35:51 +0000

Well, they aren’t pronounced the same in my accent. Twater is pronounced like ‘water’ only with a ‘t’ at the start. Same vowel sound as ‘caught’. i.e. backwards-c in IPA notation. The obscenity is pronounced with the same vowel sound as ‘cat’. i.e. /a/ in IPA notation. This might vary slightly from accent to accent. Some ‘traditional’/rural Scots accents, to my certain knowledge, would pronounce them the same. There may be others.

By: Michael Kremer

Michael Kremer — Sat, 26 Jun 2004 23:28:02 +0000

Warning: off-topic remark. I once heard Alasdair McIntyre say something like this: “if it’s worth doing, it’s worth doing poorly.” I like that as much as I do Hebb’s (or maybe more).

By: Matt Weiner

Matt Weiner — Sat, 26 Jun 2004 21:46:19 +0000

Oh, is “twater” not pronounced like the obscenity in Britspeak? I pronounce them the same, when I pronounce them at all. (Modulo the “er” of course.)

By: Matt McGrattan

Matt McGrattan — Sat, 26 Jun 2004 18:41:00 +0000

Re: ‘twater’ – yeah, for Brits like myself that’s particularly amusing. Although more so on the written page… I’ve been trying to think of ‘chmess’ ~~like areas of philosophy and apart from pretty much the whole of post~~Kantian ‘continental’ philosophy :-) I’m finding it hard to come up with one. Work on perception, and on colour in particular, often seems to be woefully under-informed about the science of colour perception. I’ve lost track of how often I hear people confidently pontificating away and making claims that are straightforwardly contradicted by things like Land’s experiments on vision from the 50s and 60s. Similarly, I do sometimes get frustrated by the general trend (post-’linguistic turn’) to make substantive inferences from language about metaphysical claims. [Of which the Twin Earth cases are one type of example] It’s irritating to sometimes hear such claims made on the basis of things that are local to the particular grammar and/or semantics of English, for example.

By: Matt Weiner

Matt Weiner — Sat, 26 Jun 2004 17:35:26 +0000

I think the twin-earth examples also helped inspire the philosophers like Dretske, Fodor, and Millikan who began to give analyses of concepts such as (very roughly) “The concept of X is the thing in the brain that is ceterus paribus caused by X.” This analysis has the consequence that it’s not always transparent what our beliefs are—we can’t always tell whether a belief expressed using the word X and a belief expressed using the word Y actually incorporate the same concept—which is a very interesting result. I’m not an expert in this sort of stuff, though, so don’t take me that seriously.
What I really want to say is—I wish they would stop calling it ‘twater’.

By: Matt McGrattan

Matt McGrattan — Sat, 26 Jun 2004 17:32:16 +0000

I think the Twin Earth thought experiments are useful but find myself convinced by Alan Sidelle's work [see Necessity, Essence, and Individuation (1989)]* which argues that what's really going on in these experiments is a teasing out of certain linguistic (and therefore analytic) principles of individuation. An important consequence of his work is that the necessity and the a posteriority in Twin Earth cases separate out. The necessity on Sidelle's account comes from the fact that in scientifically-informed English-usage being the same chemical substance as x simply means having the same chemical structure as x. There's nothing metaphysically wierd about this necessity --- it's just common or garden analyticity. The a posteriority comes from the fact that we need to head off and do some empirical investigation to find out what that structure is. On the 'Sidelle'-type account of what's going on in these cases no substantive metaphysical conclusions fall out of these thought experiments. Nevertheless, as a way of exploring or drawing attention to certain relationships between concepts they can be pretty handy. * Sidelle's book builds quite heavily on Nathan Salmon's 'Reference and Essence'.

By: Chris Bertram

Chris Bertram — Sat, 26 Jun 2004 16:25:38 +0000

Daniel, thanks ever so much for responding with such an enlightening comment! I guess I’m less bugged by the original Putnam piece than I am by the amazingly intensive cottage industry that has grown up around this particular thought experiment. But I think you’ve said enough that next time I’ll attend more rather than thinking “oh God, not another paper on TE….”

By: DonBoy

DonBoy — Sat, 26 Jun 2004 15:53:54 +0000

If you read Dennett’s piece and substitute the word “blog” for “philosophy”, much of it still applies.