In reactions, a human-human reaction is a chemical reaction between two or more human molecules. There are many different types and categories of human-human reactions, all being generalized as human chemical reactions, a dominate one being the male-female reaction, a heightened example of this being those male-female reactions (or male-male reactions, in the homosexual scenario) that enter into the famed "love the chemical reaction". German polymath Johann Goethe, for instance, is said to have outlined 36 types of human-human reactions in his 1809 Elective Affinities, some of which have already been deciphered by those including: Jeremy Adler, Karl Fink, and Libb Thims.

Equivalent human molecules
In 1885, American physical science historian Henry Adams defined social chemistry as the “study of the mutual attraction of equivalent human molecules”. [1]

References
1. (a) Samuels, Ernest. (1989). Henry Adams (human molecule, pg. 115). Harvard University Press.
(b) Gooch, George P. (1913). History and Historians in the Nineteenth Century (human molecule, pg. 240). Longmans, Green, and Co.

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