Origin and history of humankind

mid-15c., humain, humaigne, "human," from Old French humain, umain (adj.) "of or belonging to man" (12c.), from Latin humanus "of man, human," also "humane, philanthropic, kind, gentle, polite; learned, refined, civilized." This is in part from PIE *(dh)ghomon-, literally "earthling, earthly being," as opposed to the gods (from root *dhghem- "earth"), but there is no settled explanation of the sound changes involved. Compare Hebrew adam "man," from adamah "ground." Cognate with Old Lithuanian žmuo (accusative žmuni) "man, male person."

Human interest is from 1779. Human rights is attested by 1650s; human being by 1670s.

"Curst with hereditary love of pelf,

"I hate all human beings but myself ;

"Cross and perplex my wife, because she prov'd,

"Poor girl !—not rich enough to be belov'd."

["The Diaboliad, A Poem Dedicated to the Worst Man in His Majesty's Dominions," 1677] 

Human comedy "sum of human activities" translates French comédie humaine (Balzac); see comedy. Human relations is from 1640s as "interaction and connection among persons;" by 1916 as a department in a modern corporation; the phrase had been used from about 1912 in discussions of modern industry.

More than ever, perhaps, the successful manager must be a close student of men and their psychological processes. With the steady rise in intelligence, the increasing complexity of personal relations and the growing tendency of the public to interest themselves in industrial matters, the human element in factory management looms up with increasing importance; and no system of management can be successful that does not take this factor into account. [Dexter S. Kimball, "Principles of Industrial Organization," N.Y., 1913]

 Human resources is attested by 1907, American English, apparently originally among social Christians and based on natural resources. As a personnel management department in a government or corporation by 1977.

"class, sort, variety," from Old English gecynd "kind, nature, race," related to cynn "family" (see kin), from Proto-Germanic *kundjaz "family, race," from PIE root *gene- "give birth, beget," with derivatives referring to procreation and familial and tribal groups.

Ælfric's rendition of "the Book of Genesis" into Old English came out gecyndboc. The prefix disappeared 1150-1250. No exact cognates beyond English, but it corresponds to adjective endings such as Goth -kunds, Old High German -kund. Also in English as a suffix (mankind, etc., also compare godcund "divine"). Other earlier, now obsolete, senses included "character, quality derived from birth" and "manner or way natural or proper to anyone."

Phrase a kind of (1590s) indicating something like or similar to something else led to the colloquial extension as adverb (1804) in phrases such as kind of stupid "a kind of stupid (person), (one) not far from stupidity." However "good usage" once condemned as inaccurate the use as an adjective as in our kind of people, some kind of joke. All kinds is Old English alles cynnes, in Middle English sometimes contracted to alkins.