The very speeches in which Jefferson and Lincoln spoke of their hope for the future are incomprehensible to most of the voters of that future, since the vocabulary and syntax of the speeches are more difficult—more obscure—than anything the voters have read or heard. For when you defeat me in an election simply because you were, as I was not, born and bred in a log cabin, it is only a question of time until you are beaten by someone whom the pigs brought up out in the yard. The truth that all men are politically equal, the recognition of the injustice of fictitious differences, becomes a belief in the fictitiousness of differences, a conviction that it is reaction or snobbishness or Fascism to believe that any individual differences of real importance can exist. [Randall Jarrell, "The Obscurity of Poetry," 1953]
Old English felan "to touch or have a sensory experience of; perceive, sense (something)," in late Old English "have a mental perception," from Proto-Germanic *foljanan (source also of Old Saxon gifolian, Old Frisian fela, Dutch voelen, Old High German vuolen, German fühlen "to feel," Old Norse falma "to grope"), which is of uncertain origin, possibly from a PIE *pal- "to touch, feel, shake, strike softly" (source also of Greek psallein "to pluck" the harp), or from PIE root *pel- (5) "to thrust, strike, drive."
In Germanic languages, the specific word for "perceive by sense of touch" has tended to evolve to apply to the emotions. The connecting notion might be "perceive through senses which are not referred to any special organ." Sense of "be conscious of a tactile sensation, sense pain, pleasure, illness, etc.; have an emotional experience or reaction," developed by c. 1200, also "have an opinion or conviction;" that of "to react with sympathy or compassion" is from mid-14c. Meaning "to try by touch" is from early 14c. From late 14c. as "know (something) beforehand, to have foreknowledge of." To feel like "want to" attested from 1829.
c. 1300, resonable, "having sound judgment, endowed with the faculty of reason," from Old French raisonable, from Latin rationabilis, from ratio "reckoning, understanding, motive, cause," from ratus, past participle of reri "to reckon, think" (from PIE root *re- "to reason, count").
Also originally "rational, sane," senses now obsolete. The sense shifted somewhat in Middle English via "due to or resulting from good judgment," then "not exceeding the bounds of common sense."
The meaning "moderate in price" is recorded from 1660s; earlier it meant "moderate in amount" (14c.). Related: Reasonably, which is from late 14c. as "according to reason," c. 1500 as "fairly tolerably;" reasonableness.
The adjective reasonable ... denotes a character in which reason, (taking that word in its largest acceptation,) possesses a decided ascendant over the temper and passions: and implies no particular propensity to a display of the discursive power, if indeed it does not exclude the idea of such a propensity. [Dugald Stewart, "Elements of the Philosophy of the Human Mind," 1856]
What the majority of people consider to be 'reasonable' is that about which there is agreement, if not among all, at least among a substantial number of people; 'reasonable' for most people, has nothing to do with reason, but with consensus. [Erich Fromm, "The Heart of Man," 1968]
In law, "befitting a person of reason or sound sense;" reasonable doubt (1670s) is doubt for which a pertinent reason can be assigned and which prevents conviction in the minds of jurors of the truth of the charge.