With little time, less boring and effortless agreement you can build up other peoples’ knowledge. For this, cause them to put their minds together and teach each other while you keep silent. The little they know will come up like oil on the water. Then, if you still have something left to say, add your own, without fear of repeating the obsolete.
This reminds me of a story:
Nasreddin was now a reputed philosopher.
The day came when he decided to walk back and bring a tear of remembrance to native Horto, the village of his first childhood slap.
The news was fast to spread over the fences. The elder of Horto, flattered by the visit of the great man hurried to bid him:
"Pray, master, do come and share your wisdom with the people!"
"Be it" he answered.
At the heart of the market, duly mounted on a huge festive barrel Hoca addressed the crowd:
"People of Horto" he started, "do you know what I will say to you?"
"Yes we do", shouted some impertinent youngsters.
"You do!" Hoca grew red in the face and left shouting: "As you cannot add a drop into a full cup, I have nothing to say to people who know. Arrogant fools!"
After this unhappy event, the notables came again to the Hodja and insisted with their humblest apologies:
"Have patience Maulana, have patience with the simple in spirit! Come again to serve the victory of Religion and impart your wisdom to the people!"
Nasreddin, generous, accepted.
It happens that the next day, a pleasant afternoon perfumed by a gentle breeze, when Hoca mounted to his improvised pulpit, he asked again:
"People of Horto, do you know what I will tell you?"
Better prepared, some voices rose:
"No, we don't know a thing."
This appeared to be just too much for the teacher:
"Ignorants! Nothing can be built on nothing! You are hopeless!" And he left.
That evening the delegation came again to intercede with the angry Mullah:
"Wise one" they said "have mercy, don't live your people in the darkness! Please, please try a last time, come to the mosque and let us see the light!"
And he accepted.
Next day, when Hoca rose to the minbar, a silence fell upon the crowd. And he asked:
"People of Horto! Do you know what I will tell you?"
Now the villagers were puzzled on how to deal with this difficult master. Shyly, some voices advanced:
"Well, some of us do but some of us don't."
"Aha!" exulted the Mullah. "Then, let those of you who know, tell those who don't!" And he left.