In ancient times there was a man who was very fond of fur clothes and fine food. He asked a fox to give him its pelt, but the fox ran away. He then asked a sheep for its meat, but the sheep too ran away.
This idiom means that it is impossible to discuss with the vicious about getting profits from them.

周朝时有一个人非常喜欢穿皮衣服，还爱吃精美的饭食。他打算缝制一件价值昂贵的狐狸皮袍子，于是就与狐狸商量说：“把你们的毛皮送给我几张吧”，狐狸一听，全逃到山林里去了。他又想办一桌肥美的羊肉宴席，于是去找羊说：“请帮帮我的忙，把你们的肉割下二斤，我准备办宴席”，没等他说完，羊就吓得狂呼乱叫，互相报信，一齐钻进树林里藏了起来。这样，那人十年也没缝成一件狐狸皮袍子，五年也没办成一桌羊肉宴席。

这个故事原来叫“与狐谋皮”， 后来转化成“与虎谋皮”，比喻跟恶人商量要他牺牲自己的利益，那是绝对办不到的。

与狐谋皮 (yǔ hú móu pí)
【翻译】Borrowing the Skin from a Fox.
【释义】跟狐狸商量要它的皮。比喻跟恶人商量要他放弃自己的利益，绝对办不到。
【例句】他只会从别人那搜刮东西，你想让他掏钱，不是与狐谋皮吗？
【近义词】海中捞月、枉费心机、水中捞月
【反义词】行之有效、立竿见影