Argument50 情大家指正!

bayern_scienceUID: 2102974

Argument 50:

From a draft textbook manuscript submitted to a publisher.

'As Earth was being formed out of the collision of space rocks, the heat from those collisions and from the increasing gravitational energy of the planet made the entire planet molten, even the surface. Any water present would have evaporated and gone off into space. As the planet approached its current size, however, its gravitation became strong enough to hold gases and water vapor around it as an atmosphere. Because comets are largely ice made up of frozen water and gases, a comet striking Earth then would have vaporized. The resulting water vapor would have been retained in the atmosphere, eventually falling as rain on the cooled and solidified surface of Earth. Therefore, the water in Earth's oceans must have originated from comets.'

Outline:

1.作者没有提供足够的信息说明当地球被撞击之后存在的水分都会蒸发并最终gone off into space。可能是聚集在地球周围，等地球恢复到一定大小的时候有被吸引回来的
2.作者也没有排除其他可能导致地球有水的原因，不一定就来自于彗星
3.其他因素：作者没有考虑到究竟有多少彗星撞击到了地球，是不是有足够多的水分产生；也没有提供什么确凿的证据，正是由彗星这样做过
                                            ---太傻GRE作文电子书

Response:

In this analysis, to substantiate the claim that the water in Earth’s oceans must have originated from comets, the arguer cites that the water present in Earth in the incipient stage has evaporated and gone off into space and that comets are largely ice made up of frozen water and gases and brought to Earth the water when they strake it. By careful scrutiny, the argument is not well-reasoned. (is unwarranted)

First of all, water that originally present in Earth might have evaporated but as the author mentions later in the argument, the gravitation of Earth might have held some. And for that has escaped, there is still possibility that it might form ice comets over time and regained by Earth when the gravitaion of Earth become stronger. Therefore, the arguer’s claim that the water present would have gone off into space and lost is not well-reasoned.

Secondly, from Chemistry we know that, water is made up of one oxygen atom and two hydrogen atoms. Under situable circumstance, the oxygen and hydrogen gases can react to produce water, which can happen in Earth when it approached the current state. Hence even if the water originally present in Earth has evaporated and escaped, water can still be produced from the oxygen and hydrogen gases held by (originating from) Earth, which might have accumulated and formed oceans. In the argument, the arguer fails to rule out this possibility. (the arguer fails to rule out this possibility in the argument)

Finally, admittedly there is some water originating from comets striking Earth. But it is still open to doubt that how much water can be brought by comets. As we know, there are many other types of objects that strikes Earth--comet being only one of them--not all of which are made up of ice. The number of comets striking Earth may be just insignificant. In addition, even in the family of comets, there are three types: one is made up of ice; another is mainly constituted by (composed of) rocks; and the third is ferrous. Thus the number of comets that strake Earth and that is made up of ice is even less. Furthermore, not all of the water (in fact not the majority) brought by ice comets can eventually fall down onto the surface as rains (+which makes the possible contribution to the water of oceans by comets even less). Thus the arguer’s claim that the water of oceans in Earth must originate (have originated) from comets is not convincing.

In conclusion, there are flaws in the reasoning of the author (the author’s reasoning), which makes his or her claim short of legitimacy.

Word Count: 406


PS: Those in parentheses are the modifications made after completion.
    限时完成，但是没有时间检查了。