Apart from its significance as a monumental work of scholarship in several disciplines, Mumford explicitly positioned the book as a call-to-action for the human race to consider its options in the face of the threats to its survival posed by possible ecological catastrophe or industrialised warfare.

[1] The first phase of technically civilized life (AD 1000 to 1800) begins with the clock, to Mumford the most important basis for the development of capitalism because time thereby becomes fungible (thus transferable).

"the goal of eotechnic civilization as a whole...was not more power alone but a greater intensification of life: color, perfume, images, music, sexual ecstasy, as well as daring exploits in arms and thought and exploration."

The second phase, the paleotechnic (roughly 1700 to 1900), is "an upthrust into barbarism, aided by the very forces and interests which originally had been directed toward the conquest of the environment and the perfection of human nature.

The invention of coal-fired steam powered factories and the installation of capital-intensive machinery leads to a necessarily gigantic round-the-clock scale of production supported by unskilled machine tenders.