1. an observer who has little or no prior information about the events that he or she is observing or the people involved in them. In psychology experiments, the reactions of a naive observer may be highly revealing when contrasted with those of other observers who have been given selected pieces of information (or misinformation) about the observed situation or the actors in it (e.g., that a particular individual has a criminal conviction).

2. in philosophy, an observer who adopts a position of naive realism.