The wise son, the suspect neighbor: When bias builds walls

There was once a rich man in the state of Song. After a downpour of rain his wall began to crumble.

“If you don’t mend that wall,” warned his son, “a thief will get in.”
An old neighbour gave the same advice.

That night, indeed, a great deal of money was stolen. Then the rich man commended his son’s intelligence, but suspected his old neighbour of being the thief.

Allegorical Meaning

The Anatomy of Cognitive Bias

Identical Input, Opposite Judgments:

Son’s warning = “foresight”
Neighbor’s warning = “proof of guilt”

Psychological Mechanism:

In-group Favoritism: Blood ties distort perception (“my child is brilliant”).
Out-group Distrust: Social distance breeds suspicion (“the outsider must be guilty”).

Han Feizi exposes a universal flaw: We judge ideas not by merit, but by their source.

The Social Physics of Suspicion

The Wall as Symbol:

Physical wall = shattered security.
Mental wall = rich man’s prejudice separating “us” (family) from “them” (neighbor).

Weaponized Coincidence:

The neighbor’s accurate prediction—a rational observation—becomes retroactive “evidence” of guilt.

The Silent Thief: Self-Deception

The real “thief” is the rich man’s bias:

• He loses property to literal thieves.
• He loses wisdom to cognitive thieves: arrogance and tribalism.

Suspicion stole his reason long before thieves stole his gold.