价值是凝结在商品中的人类无差别的劳动,价值的源泉是劳动。这是马克思主义劳动价值理论的常识。显然,价值不能离开商品而孤立地存在,而商品不仅具有价值,又具有使用价值,这样,商品的生产就不仅要有劳动力的投入,而且还要有土地、资本、技术、管理等各种要素参与其中。马克思说过:“劳动不是一切财富的源泉,自然界同劳动一样也是使用价值(而财富就是由使用价值构成的)的源泉,劳动本身不过是一种自然力即人的劳动能力的表现。” Value is the undifferentiated work of humanity condensed in commodities, the source of which is labor. This is the common sense of Marxist labor value theory. Obviously, the value can not exist in isolation from the commodity, and the commodity has not only the value but also the use value so that the production of the commodity not only requires labor input, but also has various elements such as land, capital, technology and management participate. Marx said: “Labor is not the source of all wealth. Nature, like labor, is also the source of value (and wealth is made up of use value). Labor itself is merely a manifestation of human nature, that is, the ability of man to work.”