《淮南子·泰族训》
草木如果枝末比根本粗大，就会折断；禽兽如果尾大于腰，这尾巴就摇摆不动。
末大于本则折，尾大于要则不掉矣。
If plants and trees have larger nonessential parts than fundamental parts, they will break; if birds and beasts have tails larger than their waists, these tails will not be able to swing.