Trade union opposition to extending working hours is based on the “lump-of-labor” theory. According to this view, there are no economic advantages of such a policy, because the total amount of labor in the economy is fixed.
工会反对延长工作时间的抗议建立在“劳动合成谬误”的理论之上。根据这一观点，这样的政策毫无经济利益，因为经济学中的劳力总和是固定的。因此，工作时间延长10%只会导致就业率降低10%。