About this passageThe Kālāmas of Kesamutta describe a specific problem: teacher after teacher arrives, each promoting their own doctrine and disparaging everyone else's, and they cannot tell who is telling the truth. The reply is often quoted as a licence to believe whatever one likes, which the rest of the discourse does not support — the test it goes on to give is whether a thing leads to harm, and it is applied by examination rather than by preference.
"There are, sir, some ascetics and brahmins who come to Kesamutta. They explain and promote only their own doctrine, while they attack, badmouth, disparage, and smear the doctrines of others. Then some other ascetics and brahmins come to Kesamutta. They too explain and promote only their own doctrine, while they attack, badmouth, disparage, and smear the doctrines of others. So, sir, we're doubting and uncertain: 'I wonder who of these respected ascetics and brahmins speaks the truth, and who speaks falsehood?'"
"It is enough, Kālāmas, for you to be doubting and uncertain. Doubt has come up in you about an uncertain matter.
Please, Kālāmas, don't go by oral transmission, don't go by lineage, don't go by testament, don't go by canonical authority, don't rely on logic, don't rely on inference, don't go by reasoned train of thought, don't go by the acceptance of a view after deliberation, don't go by the appearance of competence, and don't think 'The ascetic is our respected teacher.'
But when you know for yourselves: 'These things are unskillful, blameworthy, criticized by sensible people, and when you undertake them, they lead to harm and suffering', then you should give them up."
In plainer words
The villagers said: teachers keep coming through here. Each one says their own teaching is right and everyone else's is rubbish. We cannot tell who is honest. And the Buddha said: it makes sense that you are unsure — this is genuinely an unsettled question. So do not settle it by what you were told, or by tradition, or by scripture, or by clever argument, or by how plausible it sounds, or by the fact that a teacher is impressive. Settle it by finding out for yourself whether the thing does harm. If it does, drop it.
A restatement in modern English, written for this collection. The passage above is the text; this is one way of putting it.