Thirukkural-On Wealth-On Ignorance-Kural-403

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Even a man of no learning may be considered wise,
If he holds his tongue in gatherings of the learned.

Even a man of limited knowledge, or of comparative ignorance, may expect to be adjudged as wise, if he is aware of his limitations, and does not open his mouth to speak and exhibit his ignorance in an assemblage of the learned.

The Bible envisages the same when it says

“Even a fool, when he holdeth his piece, is counted wise".
(Proverbs 17:28)

The essence of wisdom, it is commonly said, is to know when to hold one"s tongue. The present kural actually says the same thing from the reciprocal angel.