> I said exactly what I meant in that earlier note.
Lou, you just can't help yourself. And here we see why mathematicians, as a rule, are terrible teachers. Mathematicians, almost uniquely among people I think, convey as much information by what they do not say as by what they do say.
You bring to mind van der Waerden. When I read him, so many years ago, I got the distinct impression that he would convey portentous and consequential ideas with the raising of an eyebrow.
Perhaps another anecdote, if you will forgive me, comes even closer to the issue. Again years ago, I was sitting in a mathematician's office when a student came by asking for "Sally". Sally was the department secretary whose office was three doors down the hall. Like you, Lou, this mathematician, a perfectly lovely man, just could not help himself. We both knew Sally was in her office, but the mathematician's response to this innocent student asking an innocent question? He could not just point in the right direction and say that Sally is three doors down. Oh, no. Instead, he said: I know as a matter of fact that Sally is not in this office (meaning his own office in which we were both sitting).
So highly characteristic of mathematicians, this man's response was, at the same time, perfectly true and completely useless. While this state of mind can be humorous, even charming, it sucks for students (and for anybody else who wants to carry on a fruitful conversation).