Linguistic Determinism, Sign Language, and Teeth

They were the most dangerous animals on the Planet. Their coastal heritage left them a smooth, almost hairless hide incredibly efficient at dissipating waste heat. They had the ability to remorselessly pursue their quarry at a relentless pace, regardless of the mid-day sun. Not quickly, but at a steady amble that could and did last for hours at a stretch. Binocular vision and a keen sense of smell made them the ultimate predator, for they hunted in packs, communicating silently to co-ordinate their attack. A Nightmare come true.

The estimable Norm of Normblog has an intriguing article about Linguistic Determinism.

In any case, it continues to perplex me that anyone at all does subscribe to the hypothesis of linguistic determinism. Unless one makes the hypothesis true in a merely tautological sense, so that we don't allow as counting for 'thought' anything which can't be formulated in words, it seems evident that there are both pre- and sub-linguistic forms of perception, awareness, consciousness and so forth. Think about how you know - exactly - where to place your hand in catching a ball; or, more to the point, how you discriminate between the elementary sounds of which spoken words are made up, so that you can tell what words are being uttered, and thereby gain access to language and the concepts which language makes available to you.
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So I'm puzzled by those (linguists, postmodernists, discourse theorists, etc.) who argue that everything, for us, is through language. I spoke of this puzzlement once before here, in a more frivolous way than I'm doing now. Is there anyone out there who's properly versed in this area of philosophy (as I myself am not), and could help to clear up my puzzlement?

I share his puzzlement. If Linguistic Determinism is true, how come the word Aphasia exists?

Everyone now and then has had the experience of having a word "on the tip of their tongue". The concept is clearly defined within the mind, we're even consciously aware of it (unlike the ability to walk, or the exact muiscle movements required when driving a car), yet the word for it is (temporarily) misplaced, or rather, the hyperlink to the speech centre is lost.

People who have suffered Brain damage (as I have) can sometimes have rather greater than normal difficulty with this. In some extreme cases, the ability to speak is lost completely.

Jared Diamond's excellent book, "The Rise and Fall of the Third Chimpanzee" has a large section devoted to Linguistic Determinism, and the effect that the evolution of the Voicebox, and thus the Brain's Speech centre, had on our ability to think.

I had a discussion with Mr Diamond when he visited Canberra quite a few years ago. I pointed out the well-documented ability of Chimpanzees to "speak" and understand American Standard Sign Language, Ameslan. I also pointed out the various Battle Sign Languages taught in the military, and that we have a suspiciously easy time learning them. Or inventing them for new applications, even ones involving abstract concepts such as "dangerous". Our brains are hard-wired for the ability to communicate hunting signals silently, and even to convey abstract thoughts. Basically, Language came a long time before speech, thought-construct concepts before words as such. To find out when this happened in archealogical time, just look at a hominid's dentition: if it ate meat regularly, odds are it communicated.

As one of these Nightmarish creatures stood up to spook the prey, others lay in wait, then suddenly a dozen rocks thudded into their victim. Ribs splintered, breath bloodied, the quarry ran, but slower and slower as Homo Erectus implacably followed...

And people wonder why we have Wars...