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Should we also use market forces to determine scientific questions? By that reasoning, the world is 10,000 years old and evolution is a flawed theory (well, at least in the US).
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<p>We use scientific questions to determine the linguistic version of the market equilibrium.</p>
<p>I am aware of the argument you are making. "Science is not a democracy." I wholeheartedly agree. But here linguistics is basically a science of language, studying a phenomenon which is rather democratic in nature (otherwise language would have no purpose). Note that language is a medium for truth, not truth itself. You can make arguments about absolute truth in any language -- language change merely affects the customs of the medium.</p>
<p>Market forces and their analogous equivalents are pertinent when we seek what a community wants. From the perspective of evolutionary theory, the language standards of a community are established by what a community wants to use, not the other way round. I mean, arguing about absolute truth in a medium no-one would want to use is quite meaningless, right? (This is of course also why academia needs to move towards more accessible language.)</p>
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Very few people use perfect grammar constantly; making an occasional mistake is common.
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<p>However, all native speakers -- except those with disabilities -- know the grammatical rules of their language. That is the biological nature of language acquisition. Note that even orphans raised without parents learn to speak quite articulately, when no one actively taught them their native language. That is, there is no such thing as a "technical rule that most people forget to follow"; the rule then might as well not exist at all.</p>
<p>Native speakers do make mistakes, but when they do so, it is generally because of a mind burp, not out of ignorance. This usually occurs when arguing long argumentative treatises where nested clauses and nested use of noun phrases (The X of Y of Z that VP1'ed some other NP VP2'ed yet another NP...). I note that the grammatical module (so to speak) inside people's brains generally performs its rule-checking only what is in short-term working memory. By the time the mind gets to "some other NP," noun X may have slipped out of immediate working memory (having been transferred somewhere else). The grammatical module then shifts to the nearest preceding NP. Tada! Proximal concord. (Sometimes due to synesis, or in this case, a mind burp.) </p>
<p>But in the case of our two SAT questions, both our sentences fit in nicely within working memory, so it becomes far more unlikely for native speakers to make errors.</p>
<p>(Also note, that I just caught myself in several grammatical errors of my own here -- that's because I kept on re-editing my sentences halfway and forgot to change the agreement of verbs I already typed. That's another source of error. :o)</p>