early 13c., "humble, ignorant," from O.Fr. simple
, from L. simplus
"single," variant of simplex
). Sense evolved to "lowly, common" (late 13c.), then "mere, pure" (c.1300). As opposite of composite
it dates from 1425; as opposite of complicated
it dates from c.1555. Disparaging sense (mid-14c.) is from notion of "devoid of duplicity." Simply
(adv.) in purely intensive sense is attested from 1590.