Argument147 Myth小组第六次作业

airbotsUID: 2225434

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: 471          TIME: 0:30:00          DATE: 2006-11-3



The writer asserts that the cooling in earth in the mid-sixth century was probably caused by a volcanic eruption. To prop this assertion the writer provide a series of evidences and assumptions: 1)either a huge volcanic eruption or a large meteorite colliding with Earth could have created a large dust cloud throughout Earth's atmosphere tnat would have been capable of blocking enough sunlight to lower globel temperatures significantly; 2) a large meteorite collision would probably create a sudden bright flash of light and no extant historical records of the time mention such a flash; 3)some surviving Asian historical records of the time ,mention a loud boom that would be consistent with a volcanic eruption. However, this argument contains a series of logical flaws, and is therefore not forceful as it stands.

A threshold problem with this arugment involves that the writer commits a fallacy of false dilemma, and then asserts that only two possible reasons for the dimming of the sun and cause the extremely cold temperature. Nevertheless, it is completely possible that the typhoon cause the dust fly into the air and cause the dimming of the sun.Or, perhaps the temperatures drop because the magnetic pole changed in mid-sixth century, and without the protecting of the magnetic field around the earth, the climate great changed and cause the extremely cold. Without ruling out all such factors, it is not persuasive to conclude that this assertion.

Secondly, even assuming that the foregoing assumtion is right, the writer fails to convince us that the fact no extant historical records of the time mention such a flash can exclude the possibility of meteorite collision. However,It is entirely possible that  the records of the flash have lost. Or, maybe, the meteorite hit the earth in the sea that cause no flash. Without precluding others factors, it is not suasive to assert that the cold was not caused by the meteorite collision.

In the third place, the writer confuses the correlation between the fact that a loud boom and the volcanic eruption, then asserts that the former is attribute to the later, the writer fails to exclude other possible explanations for the volcanic eruption. E.g., it is equablly possible that the loud boom was cause the by the meteorite collision or earthquake, or other possible nature activities,  Each of these or other factors may cause the loud boom, the writer can not make a convictive conclusion based on this weak correlation.

All in all, the argument is not dependable, to buttress it the writer should provide futher information about the scientific analysis of the history temperatures, and collect more edvidence to exclude the possibility of meteorite collision. We also need the information about the historical records of all other nation in mid-sixth century to confirm it is the volcanic eruption which cause the cold temperates.