naive
adjective
marked by or showing unaffected simplicity and lack of guile or worldly experience
“a teenager's naive ignorance of life”
“the naive assumption that things can only get better”
SynonymsnaifOppositessophisticatedof or created by one without formal training; simple or naive in style
“primitive art such as that by Grandma Moses is often colorful and striking”
Synonymsprimitiveinexperienced
lacking information or instruction
“lamentably unenlightened as to the laws”
not initiated; deficient in relevant experience
“it seemed a bizarre ceremony to uninitiated western eyes”
“he took part in the experiment as a naive subject”
Source: WordNet 3.1, Princeton University