- "The human knowledge base is eroding as we lose languages"
- "...bilingualism strengthens the brain"
The human knowledge base is eroding as we lose languages
My primary critique of this claim is that it's just not clear what it really means. In what way does a language uniquely encode information? Harrison provides a few simple examples, mostly lexical items that show us how a particular language fore-fronted particular features to encode, and the argument is that that tells us something about that culture's perceptions of what was important to them. This is probably true to some extant, but honestly, we still do not understand language well enough to truly understand what lexical features tell us about a culture. This is hyperbole at best. But this is NOT an argument against language death per se, it's just a fact.
So what if we lose some facts about a culture's perceptions of the world? Let's assume there are 6000 language alive today. How many have already died? We don't know. For a rough estimate, let's draw an analogy and ask the question, how many humans have ever lived? A few years ago, the Population Reference Bureau did a "semi-scientific" guesstimate of this question and determined that less than 6% of all people who had ever lived, were still alive in 2002. If we assume that languages come and go at a pace that correlates with populations, then we can assume that the current 6000 living languages are about 6% of the total number of languages that ever existed. That means the total number of languages that have ever existed is around 100,000***. This means we've already lost 94,000 languages that were never documented. 94,000 language deaths. 94,000 lost knowledge bases. Oh, the horror, the horror!
Exactly how bad off should we currently be if Harrison is correct about the ill effects of language death now that we know we've lost 94,000 languages? Are we really that bad off? Clearly the answer is no, we're not that bad off. If losing 94,000 languages has not caused grave danger to humanity, why would losing another 3,000?
Yes, I agree that all languages have unique linguistic properties that are worth studying in themselves. But just because we find interesting data in every language does NOT mean we should stop language death per se. We need a broader understanding of the system of language interaction and language evolution, otherwise stopping language death may be as irresponsible as causing language death. Genetics blogger Razib Khan has made a compelling argument that "high linguistic diversity is not conducive to economic growth, social cooperation, and amity." This is just one speculative claim, but at least it's a voice on the other side of this issue.
bilingualism strengthens the brain
This is just goofy phrasing. He's referencing important neurolinguistic research, so why trivialize it by using such patently absurd language?
*I actually don't know this to be true, definitively.
**Ooooh, I'm being a little caustic there, hehe.
***This estimate is remarkably similar to the ones David Crystal discusses in his book Language Death. In that book, he says anywhere from 64,000 to 140,000 is a reasonable guesstimate. My 100,000 splits that damn near down the middle.