|Noah Webster's Dictionary|
(n.) The quality or state of being simple; simplicity.
Simpleness (2 Occurrences)
Proverbs 1:22 How long, simple ones, will ye love simpleness, and scorners take pleasure in their scorning, and the foolish hate knowledge? (DBY)
Proverbs 9:6 Forsake ye, the simple, and live, And be happy in the way of understanding. (See RSV)