Nahj al-Balagha (Peak of Eloquence)

199. Amīr al-mu’minīn, peace be upon him, said about the crowd of people: These are the people who, when they assemble together, are overwhelming but when they disperse they cannot be recognized. It is related that instead of this Amīr al-mu’minīn, peace be upon him, said: These are the people who when they assemble together cause harm but when they disperse are beneficial. It was pointed out to him: We know their harm at the time of their assembling but what is their benefit at the time of their dispersal? Then he replied: The workers return to their work and people get benefit out of them, like the return of the mason to the building site, that of the weaver to his loom, and that of the baker to his bakery.