In science, Bridgman paradox or “Paradox of Bridgman” refers to the paradox that while a living thing, i.e. powered CHNOPS+ molecule, has an entropy, as does any body in the universe, there, apparently, is no way to calculate this entropy, being that, according to standard calculation of entropy methods, one would have to either synthesize (create) or destroy (analyze) the organism in a reversible way.

The paradox was pointed out by American physicist Percy Bridgman during the famous 1946 Harvard "what is life in terms of physics and chemistry?" debate, during the course of which Bridgman commented how he saw a fundamental difficulty in the possibility of applying the laws of thermodynamics to any system containing living organisms (chnopsological organisms).

A synopsis of Bridgman’s paradoxical objection was given in French-born American physicist Leon Brillouin’s 1949 article “Life, Thermodynamics, and Cybernetics”, wherein he referred to it as the “Paradox of Bridgman”, summarizing Bridgman’s point as follows: [1]

“How can we compute or even evaluate the entropy of a living being? In order to compute the entropy of a system, it is necessary to be able to create or to destroy it in a reversible way. We can think of no reversible process by which a living organism can be created or killed: both birth and death are irreversible processes. There is absolutely no way to define the change of entropy that takes place in an organism at the moment of death.”

Bridgman’s view on this seeming paradox can also be compared to American physical chemist Martin Goldstein's 1993 chapter subsection on the entropy of a mouse, which gives led into modern human free energy theories of human synthesis. [2]

See also
‚óŹ Bridgman formulas

1. Brillouin, Leon. (1949). “Life, Thermodynamics, and Cybernetics” (abs), American Scientist, Vol. 37, pgs. 554-68; In: Biology and Computation: a Physicist’s Choice (pgs. 37-51), by H. Gutfreudn and G. Toulouse. World Scientific, 1994; in: Maxwell’s Demon 2: Entropy, Classical and Quantum Information, Computing (pgs. 73-87), Harvey S. Leff, Andrew F. Rex. CRC Press, 2003.
2. Goldstein, Martin and Goldstein, Inge F. (1993). The Refrigerator and the Universe: Understanding the Laws of Energy (section: Entropy of a mouse, pgs. 297-99). Harvard University Press.

TDics icon ns