Dynamics of Differential Equations
"Is that a 2-torus? Looks like somebody's eye with a hangover..."
"You have a stable solution, but if you kick it hard enough it goes off to infinity."
(After misspelling 'instability') "Instabity - it's a good word."
"It's not a loaf of French bread, it's an ellipse of large eccentricity that I've drawn extremely badly."
"I knew you wouldn't know, because people didn't know last year, and I can't imagine people knowing more than they did last year..."
"Clearly is different from obviously. 'Obviously' means it's obvious, 'clearly' means I'm not going to prove it now."
"This is not a waste of time." (investigating linear systems)
"The space doesn't include the inside of the tin can - it's occupied by baked beans, but not by trajectories."
"Here's our periodic orbit, in luscious green."
"We draw a subspace in glorious red... no, brightest red. Or was it deepest red? Who knows 'The Red Flag'?"
"Back, board, back!" (Proctor having problems with the blackboards slipping down)
"I must have been in an elliptic state when I wrote this."