Contradictory original poem

The original contradictory poem: "Chu people have shields and spears, and they have a reputation: our shields are strong and cannot be trapped." He also praised his spear, saying: all the advantages of my spear are trapped in things. Or, if a child's spear is trapped in a child's shield, how should one respond? An invincible shield and a trapped spear cannot stand in the same world. "

There was a man of Chu who sold both spears and shields, saying that his shield was strong and could not pierce any spear, and that his spear was sharp and could pierce any shield. A bystander asked, "What would happen if you stabbed your own shield with your own spear?" The man didn't answer. Later, because of the inconsistency in describing something. It also refers to a disjointed character or mood. Later, because the metaphor of human language action conflicts before and after, it does not correspond.