Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) said: "At the beginning of this Ummah, its young will hear from its elders, and at its end, its elders will hear from its young." Ibn Abbas (may Allah be pleased with them both) was asked: Why is that? He said: "Because the young had heard, and the elders had not heard."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 11612