Engels begins by stating that labour is not only the fundamental source of wealth and value, but that it represents the “basic condition for all human existence,” in the sense that the human mind and body have been produced by the historical process of labour. He suggests that “labour begins with the making of tools,” and therefore the first essential moment in this history was the development of bipedalism, which freed the hominids’ hands to become more dexterous and capable of crafting rudimentary implements. Thus he emphasizes that “the hand is not only the organ of labour, it is also the product of labour.”