第一， 世界上有多少水，多少钻石

第二， 水是什么物品，钻石是什么物品

第三， 钻石和水的成本的比较

和编辑效应没有什么太大关系

It is the water-diamond paradox set forth by John Law(1704)
Many people usually assert, such as Adam Smith, water is useful to human, while diamond seems to be useless, thus it is a unbelievable phenomenon that diamond has a much higher value.

Some explanations:
According to the classical school: Although diamond is useless, it is desired by human. Therefore, it has utility.in the short run, scarcity plays an important role, the scarcity of diamond make it expensive. In the long run, we can resort to either "cost-of-production solution" or "a long-run demond and supply mechanism.

From the point of view of Neoclassical economists (or Marginlists), the solution can be the marginal utility, or especially, the diminishing marginal utility.