You would feel much colder if it’s windy because the cold air is hitting your body while your clothes are wet.If there is no wind then you still feel a little breeze but it’s not as cold.
#5 - The author claims that (s)he is just trying to write the truth. The effect is that people will actually believe it more(?)
Charlie notes that he had been "foolish" to "ever have thought that professors were intellectual giants." He realizes that they are simply people, who are "afraid to reveal the narrowness of their knowledge."