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A two-part lecture course on Topology, by Professor N. The first part is in the spring semester, the second part in the following autumn semester; between them is the long summer break.

First week of the autumn semester, first lecture. Professor N comes into the room. He walks to the blackboard and picks up the chalk. He turns to the class and starts:

"Hence, ... "

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[Anectdote told by Paul Halmos in his autobiography. I quote from memory, so the details will vary.]

#lectures #HigherEducation #pedagogy #PaulHalmos

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in reply to the roamer

Picking up just where he left off. What do you mean, you don't remember - didn't you take notes?
in reply to Aaron

@hosford42

Hi, not sure what the meta joke might be? Re-reading my own post, I can imagine several meta jokes. None were planned, but some may be non-accidental sub-conscious jokes in my re-telling.

Do you mean the fact that the course subject is Topology, the study of connectedness, and the time segments of the course are clearly separated? That was not consciously intended, but very possibly my subconscious mind played an active part, who knows. (As I mentioned, I quote this from memory and in Halmos's original version most likely the lecture had a different topic. I can't findmy copy of the book.)

in reply to Aaron

Also, I have told the story many times of my grandpa doing this sort of thing. He would just resume mid sentence hours later. Much later in life, I've come to the realization that I often do it too. Nonlinear thinking!
This entry was edited (1 month ago)
in reply to Aaron

@hosford42

:-) Bless the memory of your grandfather.

There are so many levels to this case.

One is the segmentation of a spoken linear argument into separate pieces, pieces that are delivered at different points in time without any recognition of that separation in the spoken argument.

Another is the absence of social niceties in the presentation. We can read this as rudeness or personal idiosyncracy, or as a celebration of the primacy of the subject matter.

Yet another is the stark assumption by the lecturer that his audience have absorbed the previous results and are as eager as he is to see what follows from these earlier results. Again, we can see this as an oldfashioned and unjustified disregard of the student's actual learning situation, or as a bold move, making a claim on the student's undivided attention.

These different aspects interrelate in subtle ways, I love thinking about this story, it tells us so much about teaching in higher education, good and bad.

in reply to the roamer

It can also be a story of neurodivergence, of different things being natural for one person than most others. Not realizing that it might be difficult for the students to pick up where things left off, because it's so easy for him.
in reply to Aaron

@hosford42

I imagine that this is the case here, to some extent, but we don't know.

in reply to the roamer

Your memory is very accurate. :-) As related by Halmos, the lectures were given by the analyst and number theorist E.C. Titchmarsh:

‘The first half of the series ended in April, and the second half began on schedule in October. The audience was assembled, Titchmarsh strode in, picked up a piece of chalk, and said “Hence, ...”.’

(Halmos doesn't mention the subject.)

P.R. Halmos. ‘I Want to Be a Mathematician: An Automathography.’ Springer, 1985. ISBN: 978-0-387-96078-4. p.272.

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in reply to Alan J. Cain

@ajcain

Oh, bless you, thank you!!

Can't believe I got most of it right! In the initial post I had him walk up to the podium, not the blackboard, but that just did not feel right. I overrode my "do not edit posts once published" rule and changed the post. Whether my correction reflected me half-remembering this detail from Halmos's telling, or whether it simply reflecte the fact that the plot clearly demands the proximity of the imminent blackboard action, who can tell.

Delighted you could provide the specifics! Thanks!

in reply to the roamer

It is almost a reflexive action for me to track down the origin of mathematical anecdotes. :-)

When writing my historical books, I spent a lot of time tracking stories and quotations back to their origins. I vented a little bit in the preface of ‘Form & Number’ about uncited quotations and legends in the literature on mathematical beauty. :-)

in reply to Alan J. Cain

@ajcain

Couldn't resist looking up Titchmarch. He was quite a figure in his fiekd, and as a person apparently he was a man of order and habit. Here's one sympathetic obituary:

royalsocietypublishing.org/rsb…

Born in 1899, Titchmarch was just old enough to be called to serve in the first war. He did so for two years and, like many, was unable to talk about the experience in his later life. His PhD supervisor was Hardy.

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