Truth is the daughter of time, not of authority.
Age appears to be best in four things: old wood best to burn, old wine to drink, old friends to trust, and old authors to read.
Some books are to be tasted, others to be swallowed, and some few to be chewed and digested: that is, some books are to be read only in parts; others to be read, but not curiously; and some few to be read wholly, and with diligence and attention.
Do not go by revelation; Do not go by tradition; Do not go by hearsay; Do not go on the authority of sacred texts; Do not go on the grounds of pure logic; Do not go by a view that seems rational; Do not go by reflecting on mere appearances; Do not go along with a considered view because you agree with it; Do not go along on the grounds that the person is competent; Do not go along because "the recluse is our teacher." Kalamas, when you yourselves know: These things are unwholesome, these things are blameworthy; these things are censured by the wise; and when undertaken and observed, these things lead to harm and ill, abandon them... Kalamas, when you know for yourselves: These are wholesome; these things are not blameworthy; these things are praised by the wise; undertaken and observed, these things lead to benefit and happiness, having undertaken them, abide in them.
Students, when you want to say something, think about it three times before you say it. Speak only if your words will benefit yourselves and others. Do not speak if it brings no benefit.
Re-examine all you have been told. Dismiss whatever insults your own soul.