Argument47 猛拍

qhx17UID: 142079

TOPIC: ARGUMENT47 - Scientists studying historical weather patterns have discovered that in the mid-sixth century, Earth suddenly became significantly cooler. Although few historical records survive from that time, some accounts found both in Asia and Europe mention a dimming of the sun and extremely cold temperatures. Either a huge volcanic eruption or a large meteorite colliding with Earth could have created a large dust cloud throughout Earth's atmosphere that would have been capable of blocking enough sunlight to lower global temperatures significantly. A large meteorite collision, however, would probably create a sudden bright flash of light, and no extant historical records of the time mention such a flash. Some surviving Asian historical records of the time, however, mention a loud boom that would be consistent with a volcanic eruption. Therefore, the cooling was probably caused by a volcanic eruption.
WORDS: 569          TIME: 上午 01:05:01          DATE: 2006-11-2

In this argument, the author concludes that cold temperatures were caused by a volcanic eruption. To support his assertion, the author cites evidence of history record that mentioned a dimming of the sun and extremely cold temperatures. He also points out that no extant historical records mention such a flash relevant to meteorite. However, close scrutiny of this evidence and the line of reasoning reveals that they provide little credible support to the conclusion.

A threshold problem with this argument is that the author commits a fallacy of "cum hoc, ergo propter hoc" in assuming that dim sunlight is sole reason behind the temperature decreased. However, the record mentioned is insufficient to support the claim: a mere fact that a dimming of the sun coincided with the extremely cold temperatures is insufficient to conclude that the former causes the latter. To establish a general causal relationship between a dimming of the sun and the cold temperatures, other factors that could bring about the same results should be considered and eliminated. It is entirely possible that when sunlight blocked and became dim, the global temperatures had been extremely cold for many years. And it is also possible that some change happen in glacier that made the temperatures down. The author's failure to investigate or even consider the possible explanations for the temperature decrease render the consideration based upon it highly suspect.

Even assuming that causal relationship above mentioned is established, the author commits a fallacy of false dilemma on basis that volcanic eruption and meteorite collision are mutually exclusive alternatives and there is no room for a middle ground. However, the author provides no reasons for imposing an either/or choice. The author overlooks the possibility that other factors could result in extremely cold temperatures. Or possible might be adjustment volcanic eruption and meteorite collision. If that were the case, the author's assertion would be seriously undermined.

Moreover, even assuming that an either/or choice established between volcanic eruption and meteorite collision, it is unfair to draw any conclusion that volcanic eruption is the sole reason. It is unnecessarily to indicate that no bright flash present in that time. No extant historical records of such flash which coincided with large meteorite collision is unjustifiable to deny the possible occurrence of such bright flash. It might be no literature or language written described the flash. Scientists might not found the records about the flash as well. Without considering the possibilities, the author unfairly to draw any conclusion whatsoever.

Finally, the author fails to point out that volcanic eruption is only reason on basis of some surviving Asian historical records of that time. The author ignores the possibilities that a loud boom might be consistent with other factors, such as earthquake, tsunami. Meanwhile the Asian records described the weather condition of Asian, and they are not typical of the global temperatures decrease. With such mentioned dubious evidence, the author unfairly to make such conclusion.

In sum, the argument is unconvincing as it stands. To bolster it, the author must provide clearer evidence that cold temperatures is because the block of sunlight. To better assess the argument, it would be useful to know that volcanic eruption and meteorite collision is mutually an exclusive alternatives. Also useful would be information about meteorite collision unhappened in that time, and a loud boom is just from the volcanic eruption, and Asian records would be representatives of the global.