According to the dictionaries, simple means:
foolish; easily deceived:
- He’s a very simple young man.
And naive means:
a very simple person!
Cambrige Dictionary defines naive in the following way:
Too willing to believe that someone is telling the truth, that people's intentions in general are good, or that life is simple and fair. People are often naive because they are young and/or have not had much experience of life.
It is vague now! To me they meant the same, but I guess there is something missing here that I don't know! How can I differentiate between them? How do you interpret them?