Belief and knowledge

[Darkstar]

Belief is believing something to be true. There can be varying degrees of belief up to certainty. In order for belief to be knowledge, not only must the belief be true, but the one holding the belief must be able to justify it (if they believed it and it were true, but they had not justification, they would simply have guessed correctly, and one wouldn't say they knew the thing beforehand.) That is why knowledge is sometimes called "justified true belief".

One cannot know something without also believing it.