Is there an English equivalent to this familiar saying used in India:
Don't speak unless you can improve silence.
The saying loosely means it is better to be silent than prattle on about something.
There's this fairly famous saying:
"Better to remain silent and be thought a fool than to speak and remove all doubt."
A quick internet search indicates that this saying has been attributed to Mark Twain, Abraham Lincoln, and Confucius, among others.
Our mamas always told us:
If you don't have anything nice to say, don't say, anything at all!
There's a proverb:
"Speech is silver, silence is golden".
Speech is of time, silence is of eternity.
- Thomas Carlyle, Sartor Resartus
It is the wise head that makes the still tongue.
- W. J. Lucas
Let not thy tongue run away with your brains
I'm not sure whether it is of English origin, but it has been around for a while, since it can be found in:
Gnomologia: Adagies and Proverbs; Wise Sentences and Witty Sayings, Ancient and Modern, Foreign and British collected by Thomas Fuller; B. Barker ... and A. Bettesworth and C. Hitch, 1732
A modern version can also be found (on-line at least):
Let not your tongue run away with your brains.
it is an old Arabic proverb, in spanish litrature they attributed this saying to the arab way way back in the moorse time. another one from Arabia. if talking is made of silver, silence is from gold.