A men crosses a deep and large river by a piece of wood. It is seen there that the man takes the piece of wood to the other side, and the piece of wood also takes the man to the other side.
कश्चित् तरति काष्ठेन सुगम्भीरां महानदीम्। स तारयति तत् काष्ठं स च काष्ठेन तार्यते॥