女巫的超前思維
親愛的經濟學家：
Dear Economist,
有一個關於古羅馬末代君王塔爾坎(Tarquin)的傳說。一位老女巫走到塔爾坎面前，提出以高昂的價格賣給他9本預言書。塔爾坎對這一提議不以爲然。女巫燒燬了其中的3本書，然後提出以原價賣給他剩下的6本。塔爾坎再次拒絕了。
There is a legend about the last king of the Romans, Tarquin. An old witch came to Tarquin, and offered to sell him nine books of prophecy at an exorbitant price. Tarquin laughed at the offer. The witch burned three of the books, and then offered to sell him the remaining six for the original price. Tarquin refused again.
女巫又燒燬了3本，然後同樣以最初9本的價格向塔爾坎出售剩下的3本。這一次，塔爾坎擔心自己可能會錯失一些寶貴的東西，於是以女巫索要的價格買下了剩餘3本書。這反映了什麼樣的需求曲線呢?
The witch burned three more books and offered to sell Tarquin the three books that were left for the original price that she had demanded for nine. This time Tarquin was scared that he might be losing something precious, and bought the remaining three books for the price that the witch asked. What sort of demand curve is that?
克里斯·麥克馬洪(Chris McMahon)通過電子郵件發送
Chris McMahon, by e-mail
親愛的麥克馬洪：
Dear Mr McMahon,