"Value" is the first category of economics, referring to the economic value and commercial value. As a philosophical concept of value for the first probably by the 18th century British philosopher David Hume (David H ume, 1711-1776) raised. He published in 1739-1740 in "Human Nature," a book made to pay attention to "yes" and "should" difference, whether from "a" push "should," This is a problem of the need to be explained. The "yes" and what "should be" how the difference, in essence, is the difference between "fact" and "value".
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