Arguments for the Chomskyan thesis

A. Speed of acquisition. All mentally healthy children learn to speak the language that they are exposed to within the first few years of life. We are all familiar with how difficult it is to learn foreign languages as an adult or even as a teenager, yet children acquire those same languages flawlessly with no conscious effort. We do not work to learn our first languages—it “just happens”—despite how very complex languages are. This suggests that we are programmed for the task.

B. All humans learn to speak. In contrast to singing or athletic ability, all humans acquire the ability to speak fluently. This includes a great many who are mentally deficient in other ways. This suggests that there is a specific hardwiring for language that overrides culture or individual abilities, as for example, walking.

C. The critical-age hypothesis. Language learning ability erodes as we get older.

1. Age gradation. Small children of immigrants learn the new country’s language perfectly; people who come to a new country in their early teens often master the language almost perfectly but have slight accents; people who immigrate as full adults often never fully master the new language even with considerable effort.

2. Maturational stages in nature. This parallels a common tendency in organisms for certain genetically specified features to be programmed to appear at certain stages in the life cycle, then erode as they are no longer necessary. Just as ducklings are programmed to fixate on a large moving object as their “mother” and caterpillars are programmed to become butterflies at a certain point, we may be programmed to learn languages early. Our lesser ability later in life would trace to the fact that there is no reason connected to survival for us to be programmed to learn languages later.

3. The case of Genie. A girl named Genie was kept in isolation from human contact from the time she was a toddler until the age of 13 and beaten if she tried to talk. After her release, she never learned to speak fluently, producing such sentences as I like elephant eat peanut.

D. Poverty of the stimulus. Humans learn language without being taught, and despite the fact that the language they hear is fragmentary and full of false starts. Language as it is actually spoken is rarely as carefully planned out as it is in the artificial medium of writing. Here is a transcription of college students speaking:

A: Yeah. It doesn’t help the tree but it protects, keeps the moisture in. Uh huh. Because then it just soaks up moisture. It works by the water molecules adhere to the carbon moleh, molecules that are in the ashes. It holds it on. And the plant takes it away from there.

B: You know, you said how silly it was about my, uh, well, it’s not a theory at all. That the more pregnant you are and you see spots before your eyes it’s proven that it’s the retention of the water.

E. Specificity of language deficits. Damage to the brain produces language deficits in specific ways that seem to correspond to two very specific areas of the brain where the ability to speak seems to be located.

1. Broca’s area appears to control grammar; one person with damage to this area spoke like this:

Yes…ah…Monday…ah…Dad and Peter Hogan, and  Dad…ah…hospital…and ah…Wednesday…Wednesday nine o’clock and ah Thursday…ten o’clock ah doctors…two…two…an doctors and…ah…teeth…yah…

2. Wernicke’s area appears to control meaning and comprehension; one person with damage to this area spoke like this:

Oh sure. Go ahead, any old think you want. If I could I would. Oh. I’m taking the word the wrong way to say, all of the barbers here whenever they stop you it’s going around and around, if you know what I mean, that is tying and tying for repucer, repuceration, well, we were trying the best that we could…

3. Myrna Gopnik, a linguist at McGill University, and several geneticists have studied a multigenerational family in England in which many people speak rather slowly and often make the kinds of mistakes one would expect of a foreigner, such as The man fall off the tree and The boys eat four cookie. Their condition is termed specific language impairment. Presented with a drawing of a bird-like creature, told that it is called a wug, shown a picture of two of the creatures, and asked, “Now there are two of them; there are two…?,” the impaired members of the family will either wave away the question or answer along the lines of wugness.

4. The affected members of the family have been shown to have a defect in the gene FOXP2.

F. Apes versus humans. It has recently been discovered that chimpanzees and other apes also have the FOXP2 gene but in a slightly different form. This suggests that our version of the gene may give us the ability to use language that apes fall short of.