True knowledge and insights first come from thinking and doubting.
——Rockwell
Spending time on thinking is the most time-saving thing.
——Cousins
Thinking is the self-talk of the soul.
——Plato
Those who are not determined to cultivate the habit of thinking will lose the greatest joy in life.
——Edison
The development of the thinking world, in a sense, is the continuous getting rid of surprise.
——Einstein
Doubts grow with knowledge.
——Goethe
Greatness is not only earth-shattering in his career, he often thinks deeply and quietly.
——Krylov
It is embarrassing to fight against one's own heart, but this kind of victory is a sign of a thoughtful person.
——Democritus
1. Trenching operation.
Ride on the two tracks of the excavator in the middle of the ditch and walk backwards. The upp