Conjunction
Upon any less condition than (the fact or thing stated in the sentence or clause which follows); if not; supposing that not; if it be not; were it not that; except; as, we shall fail unless we are industrious.
Source: Webster's dictionaryMan cannot discover new oceans unless he has the courage to lose sight of the shore. André Gide
You never know what is enough unless you know more than enough. William Blake
To be wrong is nothing unless you continue to remember it. Confucius
Don't open a shop unless you like to smile. Chinese Proverb
Don't speak unless you can improve on the silence. Spanish Proverb
Don't celebrate someone's departing unless you know who will succeed him. Arabic Proverb