Belief is the psychological state in which an individual holds a proposition or premise to be true.
The terms belief and knowledge are used differently in philosophy.
Epistemology is the philosophical study of knowledge and belief. The primary problem in epistemology is to understand exactly what is needed in order for us to have true knowledge. In a notion derived from Plato’s dialogue Theaetetus, philosophy has traditionally defined knowledge as “justified true belief”. The relationship between belief and knowledge is that a belief is knowledge if the belief is true, and if the believer has a justification (reasonable and necessarily plausible assertions/evidence/guidance) for believing it is true.
A false belief is not considered to be knowledge, even if it is sincere. A sincere believer in the flat earth theory does not know that the Earth is flat. Later epistemologists, for instance Gettier (1963) and Goldman (1967), have questioned the “justified true belief” definition….