Applause (n.) is what a lecturer gasps for once he has stopped trying to help anyone — he ends up reading Socrates like an opera libretto.
Applause (n.) is the lecturer's real aim, betrayed when he walks out dejected without it, or asks everyone how he delivered the bit about Pan and the Nymphs.
Applause (n.) is the sign a lecture was worthless: if you have time to praise me, what I am saying is not worth much.
Applause (n.) is the one thing the virtuoso never studied: he knows his high and low notes but not what a crowd is or what its praise is worth, and so he trembles.
Applause (n.) is the lecturer's secret master: received coolly, he leaves in low spirits; applauded, he goes round asking "How did I render the passage about Pan and the Nymphs?"