I suppose they don't know what they miss, anyhow." There was such an air of "you and I" about Mr.McDowell that Amory very nearly pushed him out of the open window when he said this.

...

Next February his mother would wonder why he didn't make a club and increase his allowance...

simple little nut....
Through the smoke and the air of solemn, dense earnestness that filled the room would come the inevitable helpless cry: "I don't get it! Repeat that, Mr.Rooney!" Most of them were so stupid or careless that they wouldn't admit when they didn't understand, and Amory was of the latter.

He found it impossible to study conic sections; something in their calm and tantalizing respectability breathing defiantly through Mr.Rooney's fetid parlors distorted their equations into insoluble anagrams.