There is a widely shared story about Plato and Socrates finding wheat in a field, and using it as a metaphor, generally for love. Examples: Actorsfit.com, David Ding and Love, Marriage, Happiness, Affair, and Life:
One day, Plato asked Socrates What love is. Socrates said: I ask you to go across this rice field, pick up and bring back the biggest and best ear of wheat, but remember one thing, you cannot go back, and you just have one chance. [...]
A Chinese version of the story, titled The Largest Ear of Wheat, appears in a primary school textbook. It uses it as a metaphor for seizing opportunity.
I have always doubted that dialogue actually happened. I read just a little of the Socratic dialogues, so I can't say for sure.
So does this really appear in one of Plato's dialogues?
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I try to translate the Chinese version here:
Socrates asked his disciples to pick up the biggest ear of wheat along their way on one condition, they can NOT go back to pick wheat they have already passed.
The disciples walked through the field, looking at an ear of wheat and shaking their heads; looking at another and shaking their heads again. Some disciples did try to pick a few ears, but they were not satisfied and threw them away. They thought that the biggest one was still lying ahead, as they believed there were still many opportunities, so there was absolutely no need to make decisions prematurely.
In the end, they walked out of the field with empty hands. Socrates then said seizing opportunity in life is like walking in the wheat field while looking for the biggest ear of wheat. Some people saw a full-grained one and picked it up without overthinking if this was the biggest one; some people looked around and missed the opportunity again and again.