"We can think of the stock of knowledge, or as Teilhard de Chardin called it, the "noosphere," and consider this as an open system, losing knowledge through aging and death and gaining it through birth and education and the ordinary experience of life. ...A machine ...originated in the mind of man, and both its construction and... use involve information processes imposed... by man... The cumulation of knowledge... is the key to human development... especially economic development. ...[W]here the material capital has been destroyed by war, as in Japan and Germany... knowledge was not destroyed, and it did not take long... for most of the material capital to be reestablished..."