The Wealth of Nations
Book I: Of the Causes of Improvement in the productive Powers of Labour

Of the Wages of Labour: In this section, Smith describes how the wages of labour are dictated primarily by the competition among labourers and masters. When labourers bid against one another for limited employment opportunities, the wages of labour collectively fall, whereas when employers compete against one another for limited supplies of labour, the wages of labour collectively rise. However, this process of competition is often circumvented by combinations among labourers and among masters. When labourers combine and no longer bid against one another, their wages rise, whereas when masters combine, wages fall. In Smith's day, organised labour was dealt with very harshly by the law.
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