Independent thinking ability is an essential ability for scientific research and invention. Any important scientific creation and invention in history cannot be separated from the inventor's independent and in-depth solution to the problem.

-Hua, mathematician

Imagination is more important than knowledge, because knowledge is limited, and imagination summarizes everything in the world, promotes progress and is the source of knowledge evolution. Strictly speaking, imagination is a real factor in scientific research.

-Einstein, American physicist

Being lazy in thinking, unwilling to delve into and deeply understand, complacent or content with trivial knowledge are all reasons for poor intelligence. This kind of poverty can be described in one word, and that is "stupidity".

-Gorky, writer of the former Soviet Union