众所周知,狗是可以拿耗子的。但狗拿耗子未必有猫专业:论看家,猫不如狗;论拿耗子,狗不如猫。通常,我们很难判断是大米贵还是黄金贵。根据政治学原理,我们知道,它们是可以实现等价交换的。当然,等价交换不是等重交换,所以一克黄金远比一斤大米值钱。可是,在饥荒时期或是战争年代,一斤大米却远 As we all know, dogs can take the mouse. However, dogs do not necessarily have to take the cat dog profession: on the housekeeping, cats better than dogs; to take the mouse, the dog as good as a cat. Often, it is hard to tell whether rice is expensive or expensive. According to the principles of politics, we know that they can be exchanged for the equivalent. Of course, equivalent exchange is not equal exchange, so one gram of gold is worth more than a pound of rice. However, in the famine or the war years, a pound of rice is far away