The story happened in a bumper wheat field. There are two farmers, A and B, who both want to find the biggest ear of wheat. They stood at both ends of the wheat field and began to look for it.
Farmer a's strategy is to walk in a straight line first, walk from one end to the other, and pick out the biggest ear of wheat along the way. Then, he went back and picked out what he thought was the biggest ear of wheat. Finally, he compared the two selected ears of wheat and chose the largest one as the final result.
Farmer B's strategy is to carefully observe some ears of wheat in the wheat field and choose the one he thinks is the biggest. Then, he observed another part of the ear of wheat and picked out the biggest one he thought. Finally, he compared two ears of wheat and chose the biggest one as the final result.
After some efforts, both farmers found what they thought was the largest ear of wheat. However, when they compared the ears of wheat together, they found that the ears of wheat found by farmer B were much larger than those found by farmer A.
This story tells us that when making decisions, we should try to avoid blindly moving from one extreme to the other, but make the best choice through observation, analysis and comparison. This is the famous Pythagorean paradox and one of the foundations of modern optimization theory.