Definition of simples:
(adj) :
Uncomplicated; lacking complexity; taken by itself, with nothing added.
(adj) :
Easy; not difficult.
(adj) :
Without ornamentation; plain.
(adj) :
Free from duplicity; guileless, innocent, straightforward.
(adj) :
Undistinguished in social condition; of no special rank.
(adj) :
(now colloquial, euphemistic) Feeble-minded; foolish.