Is it full?

Master Wude (947–1024 CE), also known as Master Shan Zhao, was a prominent Chan (Zen) master of the Song Dynasty and a key figure in the Lingji (Rinzai) lineage. Born in Taiyuan, Shanxi Province, he became a disciple of Master Shoushan Xingnian and played a crucial role in shaping Chinese Chan Buddhism during the Song era.

A student told Master Wu De: “I’ve learned enough under you. I wish to travel now.”
Wu De: “What is ‘enough’?”
Student: “Enough means full — no room for more.”
Wu De: “Before leaving, fill a basin with stones.”

The student brought a basin heaped with stones.
Wu De: “Is it full?”
Student: “Full.”
Wu De scooped sand into the basin — it settled between stones.
“Full now?”
“Full!”

Wu De sprinkled lime over the mix — no overflow.
“Full?”
“Full!”

Wu De poured in water — absorbed without spilling.
“Full?” he asked once more.

Cultural & Philosophical Notes

The Illusion of “Full”:

The student’s “full mind” symbolizes spiritual complacency. Wu De’s demonstration reveals:

Stones = Basic knowledge >> Sand = Refined understanding

Lime = Subtle wisdom >> Water = Fluid insight
True learning never “fills” — it expands.

Humility as Receptivity:

Each addition without overflow mirrors how emptying the “self” creates infinite capacity for wisdom.

Wu De’s Final Question:

The unanswered “Full?” becomes a sword cutting through:

Student’s attachment to “completion”

All notions of hierarchical knowledge

Enlightenment is realizing the question itself is the answer:
The mind is a bottomless basin.