2. The industry is good at diligence, and it is barren of play; What is done in thinking is destroyed in following-Han Yu

3. Learning without thinking is useless, thinking without learning is dangerous-Confucius

4. Knowing is not as good as being good, and being good is not as good as being happy-Confucius.

A threesome requires a teacher. Choose good and follow it, change evil and follow it-Confucius.