------题目------
The following appeared as part of an article in a health and beauty magazine.
'A group of volunteers participated in a study of consumer responses to the new Luxess face cream. Every morning for a month, they washed their faces with mild soap and then applied Luxess. At the end of that month, most volunteers reported a marked improvement in the way their skin looked and felt. Thus it appears that Luxess is truly effective in improving the condition of facial skin.'
------正文------
In this argument, the arguer asserts that Luxess is very effective in improving the skin of face. To support his conclusion, the arguer illustrates a study in which volunteers' facial skin is improved in a month as the result of the usage of Luxess. Though the arguer's view seems plausible, in my opinion, it commits several logic flaws.
First of all, the arguer fails to give any information indicating it is a objective and scientific study. He doesn't tell us about how the volunteers are selected or the actual number of the volunteers. Scientists tell us that people's conditions of facial skin can be quite diverse. Perhaps the selected volunteers are all of the same kind of skin. In this case, they can't represent the real condition of all the consumers. Or maybe the selected volunteers never wash their face before, and when they do this, their face condition is greatly improved. And also, the number of the volunteers may be too small to say anything. To convince us, a more comprehensive study is needed.
Moreover, the arguer fails to exclude some other factors which may improve the volunteers' face condition. As the arguer describes, the volunteers wash their face before applying Luxess. Maybe the mild soaps are the real cause of their face conditions' improvement. Additionally, in order to convince us, the arguer should make a comparison between the volunteers who use Luxess and those who do not. only in this way, the arguer can give a telling support to his view.
Last but not least, common sense tells us that the improvement of one's skin condition is a long-term project. In some cases, after a short improvement the condition of skin deteriorates greatly. The study mentioned in the argument lasted only one month and this can't indicate Luxess will work in the next few months. So the arguer has to give a follow-up study to the tested volunteers.
In the final analysis, the arguer draws an untenable conclusion that Luxess can effectively improve the condition of facial skin. He fails to prove that the study is a objective one. Furthermore, he overlooks to exclude some would-be factors. At last, the period that Luxess can work is also neglected.