The first part: (paragraph 1 ~ 2) quotes famous sayings of celebrities to put forward the central argument: academic research should be skeptical. The second part: (paragraphs 3 ~ 5) demonstrates the first sub-argument: doubt is a necessary step to distinguish falsehood from falsehood in negation. Part III: (Paragraph 6) Demonstrate the second argument: Doubt is the basic condition for establishing new theories and inspiring new inventions in a positive way. This answer is answered by Xia Ziyou _ Apple Reference Moon Boat Education Resource Network. I hope it will help you ~ If you are satisfied, please adopt it in time. Thank you! O(∩_∩)o I wish you progress in your studies ~