【kaleidoscope】小组第6次作业 argument53 by rjyuu

rjyuuUID: 2591508

TOPIC: ARGUMENT53 - Thirteen years ago, researchers studied a group of 25 infants who showed signs of mild distress when exposed to unfamiliar stimuli such as an unusual odor or a tape recording of an unknown voice. They discovered that these infants were more likely than other infants to have been conceived in early autumn, a time when their mothers' production of melatonin-a hormone known to affect some brain functions-would naturally increase in response to decreased daylight. In a follow-up study conducted earlier this year, more than half of these children-now teenagers-who had shown signs of distress identified themselves as shy. Clearly, increased levels of melatonin before birth cause shyness during infancy and this shyness continues into later life.


In this argument, the author claims that increased levels of melatonin before birth cause shyness during infancy and this shyness will continue into later life. To support his conclusion he cited a study conducted on 25 infants and made some reasoning. Although at first glance this argument seems to be appealing, after clearly examining, we may find it contains several logic flaws which undermines its credibility.

To start with, the author simply assumes that the shyness showed by these 25 teenagers is special compared with most people, but he provides no evidence to substantiate this crucial assumption. It is true that more than half of these teenagers showed signs of distress identified themselves as shy. But it is entirely possible that all individuals behave like this when they step into their adolescence. If the 25 teenagers are of no special, what’s the point of talking about what makes them that unusually shy?

Another problem lies in that even if these teenagers are abnormally shy, the author further assumes that this is due to the effect of increased levels of melatonin. The author fails to rule out the possibility that the decreased daylight, or any other factors changing with season, may cause other metabolism chances in human body attributing to individual’s shyness. And although melatonin is known to affect some brain functions, there is no direct proof indication that it plays a role in affecting the baby’s rather than the mother’s brain, not to mention causing shyness--in fact the contrary is entirely possible, maybe melatonin is indeed effective in making people more extroverted, yet this effect is counteracted by other chemical mechanism in human body. In sum, unless the author could provide more specific evidence showing how melatonin works, he can not convince us it is this hormone brings about the individuals' unusual shyness.

Finally, the study itself is extremely dubious. The author didn't provide us with any information concerning how the study was conducted. And obviously 25 is a sample too small to be representative. It is entirely possible the parents of these babies happened to be shy of themselves, thus we could hardly determine the features of the babies is an effect of gene or melatonin. And since the argument relies on a specious study, the reliability of the author’s conclusion is open to question.

In sum, the argument is not so convincing as it stands. The author had better take all the factors discussed above into consideration to make the argument more thorough and acceptable.