8 The exchange of folk ideas and formal ideas, especially those with broad social significance, cannot be simply understood as one-way. When researchers of the history of ideas find that some great ideas from great minds have a humble origin, sometimes they may feel that Embarrassment. If we allow any relatively stable society or culture as a whole, we will find that it is very difficult to draw a clear line between formal ideas and their corresponding folk ideas. The most accurate summary of the main point of this text is:. ['The exchange of folk and formal ideas is complex.', 'Some great thinkers are often influenced by folk thought.', 'Researchers in the history of thought need to change their views on folk thought.', 'Folk thought and formal thought together form a stable social culture.']