A 20 manpower engine, shown in the 1670s vacuum engine experiments of German engineer Otto Guericke.
In economics, manpower, from 1862, is a loosely defined term referring to power available from or supplied by the physical effort of human beings or the total supply of persons available and fitted for service. [1]

In the late 18th century, John Smeaton equated one horsepower to 5 men or to 22,916 pounds raised on foot high in one minute. [2]

In 1932, in efforts to rid the economic system of the use of paper money, American engineer Howard Scott stated a "energy value" approximation for human power: [3]

“Technology has introduced a new methodology in the creation of physical wealth. It is now able to substitute energy for man hours on the parity basis that 1,500,000 foot-pounds equals one man's time for eight hours.

National income under the price system consists of the debt claims accruing annually from the certificates of debt already extant. Physical income within a continental area under technological control would be the net available energy in ergs, converted into use-forms and services over and above the operation and maintenance of the physical equipment and structures of the area.”

In comparing the two values, Smeaton's calculation, in the phraseology of Scott, equates to 2,200,000 foot-pounds of one man's time for eight hours.

In these sorts of efforts to equate or put a value on human effort, work output, or energy expenditures, in the attempted reduction of all human activity to the number of buckets of water a human can lift out of mine per unit time, modeled on the 1782 calculations of steam engineers Matthew Boulton and James Watt, falls into state of illogic. This becomes particularly apparent in relation to quantifications such as Forbes' annual list of the world's 100 most powerful, i.e. "world power", men and women,

See also
‚óŹ Energy slave

1. Manpower – Merriam-Webster Collegiate Dictionary, 2000.
2. Hills, Richard L. (1989). Power from Steam (pg. 89). Cambridge University Press.
3. Scott, Howard. (1933). A Thermodynamic Interpretation of Social Phenomena (notes on), Formerly titled “Integrating the Physical Sciences in Attacking Social Problems”. Archives.

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