"In the first stages of the industrial revolution, animals were used as machines. As also were children. Later, in the so-called post-industrial societies, they are treated as raw material. Animals required for food are processed like manufactured commodities. ... This reduction of the animal ... is part of the same process as that by which men have been reduced to isolated productive and consuming units. Indeed, during this period an approach to animals often prefigured an approach to man. The mechanical view of the animal's work capacity was later applied to that of workers."