Tiruvalluvar

“ Let those who list speak things that no delight afford,
'Tis good for men of worth to speak no idle word.
Let the wise if they will, speak things without excellence; it will be well for them not to speak useless things. ”

“ Words without sense, while chafe the wise,
Who babbles, him will all despise.
He who to the disgust of many speaks useless things will be despised by all.
Kural-192
Words without sense, where many wise men hear, to pour
Than deeds to friends ungracious done offendeth more.
To speak useless things in the presence of many is a greater evil than to do unkind things towards friends.
Kural-193
Diffusive speech of useless words proclaims
A man who never righteous wisdom gains.
That conversation in which a man utters forth useless things will say of him "he is without virtue." ”