And sort of whimsically they said, " Let's call the object houses." And let's suppose everyone has a house and people have preferences over houses and they can trade houses, but they can't use money.

他们有点异想天开地说：“我们把这些物体称为房屋吧。”假设每个人都有房子，人们对房子有偏好，他们可以交易房子，但不能使用金钱。