In many answers, here, philosophers talk about justified beliefs. I would like to ask if there is any difference between a justified belief and a rational belief.

There may be some difference insofar as a justified belief is usually considered a belief that is backed up by some evidence, and there may be times when it is rational (or not irrational or unreasonable) to have a belief even if one is quite uncertain about evidence. To use a homely example: You might have a vague feeling that you left your car keys back at the office and it would be rational for you to believe that is true (and go back to the office to check) even though your vague feelings don't count as sufficient evidence to make your belief fully justified. So, while there may be a difference, the two terms might be used interchangeably, especially if you hold what is sometimes called evidentialism, according to which the only beliefs that are rational and justified are those that you have evidence for. This is distinct from forms of what is sometimes called reliabilism, the view that a belief (even without evidence) may be justified if it is produced by a reliable means.

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