Elizabeth Brauß gave a really wonderful performance of Schubert’s first set of Impromptus at a concert a few years ago. The BBC have broadcast it again. Listen -- it will make your day better!
www.bbc.co.uk/sounds/play/... (starting at 5.12.40 in)
#Schubert #Piano
Exactly!
Empty bookshelves in newly redecorated room with William Morris wallpaper behind
It almost seems a shame to hide the new wallpaper with books ... but needs must!
#booksky
A quick blog post commenting on the claim by Alex Oliver and Tim Smiley to have shown that the “easy” direction of Church's Thesis is wrong.
I'm not persuaded -- and neither should you be!
www.logicmatters.net/2026/04/06/p...
#philsky #mathsky
One of my favorite works by Schubert -- his Impromptu No. 3 in G-flat major -- played superbly by German pianist Elisabeth Brauß and posted by German public broadcasting.
www.youtube.com/watch?v=4tWc...
Elisabeth Brauss played Mozart's 23rd Piano Concerto at the Cartagena Festival de Música ten days ago.A terrific performance she evidently much enjoyed.
www.youtube.com/watch?v=rX5c...
This tells you a lot more about LW than about his vary various Cambridge contemporaries.
There's a new version of my *Introducing Category Theory* now available -- a freely downloadable PDF and also a very-cheap-for-its-size pbk. Enough corrections/improvements to count as a "third edition". For info/link see logicmatters.net/categories
Please spread the word! #MathSky #PhilSky
The second issue of the new Journal for the Philosophy of Mathematics is now online (open access). Includes five pieces on sets and pluralities which (on a quick browse) seem interesting and good. Take a look! #MathSky #PhilSky riviste.fupress.net/index.php/jpm
Today’s epiphany… here the adoration of the magi by Fra Angelico & Fra Filippo Lippi 1440-60. National gallery of art Washington DC.
A new blog post about using AI in proofreading the upcoming revised 2nd edition of my category theory book. Might be of interest to other maths writers. www.logicmatters.net/2025/12/28/a...
#MathSky
Oddly the video has disappeared. I do hope not because Elisabeth was herself unhappy with her performance which her audience obviously loved.
There will be a revised version of my category theory book in January. Mostly minor changes for reader-friendliness. But I have expanded the short chapter on ETCS at the very end of the book into two short chapters. Here's a draft: www.logicmatters.net/resources/pd... Comments very welcome! #MathSky
Wonderful concert by Elisabeth Brauss at Wigmore Hall on Tuesday. Her Beethoven Op. 110 particularly moving -- www.youtube.com/watch?v=Puyd...
Paul Klee
The Bounds of the Intellect, 1927
It is out: it is amazing.
Daily Nous has a nice list of currently active philosophy blogs at dailynous.com/2025/09/18/t... It doesn't mention Logic Matters, but it staggers on into its twentieth year, still with occasional logic and phil maths content, at www.logicmatters.net/blog
CD cover ...black and white photo of Lea and Thomas
New double CD of Lea Desandre and Thomas Dunford (and the Jupiter Ensemble) performing Dowland and Purcell. Absolutely superb playing and often extraordinarily moving. (Had the good fortune to see them live at Wigmore Hall last week -- just stunning.)
Cover of forthcoming CD by the Pavel Haas Quartet
CD Forthcoming soon! Love the cover photo :)
First 5 star Amazon rating AND first typo report for new edition of *Introducing Category Theory*. Ah well ...
New blog post ... on Van Gogh, Deryn Rees-Jones (@notjustdancing.bsky.social), Proust, Clive James: www.logicmatters.net/2025/07/12/p...
I've updated my page of links to entry-level lecture notes and online books on category theory.
The page is visited a lot (3K times a month) so I ought to try to keep it in good shape. So any additions/corrections will be really welcome!
www.logicmatters.net/categories/
#mathsky #philsky
The gently-paced notes aim to be pretty accessible even if you have a relatively modest mathematical background. Could be useful prelim reading if you are taking an industrial strength course next term/semester. Or if you just want to get to know something about what the categorial fuss is about!
Part of cover ... author/title in white on red background
ICYMI At last, there is a pbk version of my notes *Introducing Category Theory*, 2nd edn., ISBN 1068346701. Amazon-only print on demand to keep the price minimal for a 500pp book. Or you can still download the PDF from logicmatters.net. Spread the word :)
#mathsky #philsky
Part of cover image, author/title in white on red background
Sound the trumpets ... At last, at last, there is a pbk version of my notes *Introducing Category Theory*, 2nd edn., ISBN 1068346701. Amazon-only print on demand to keep the price minimal for a 500pp book. Or you can still download the PDF from logicmatters.net. Spread the word :)
They were simply amazing! And with their new violist have they ever sounded better?
But that’s surely not a “trick” … it’s just applying about the most fundamental fact about triangles twice ….
Oops sorry I missed your earlier post!
It’s quite trivial. No pythagoras or Cartesian coordinates needed.
Move top apex to bottom right of big square, and area stays the same (why?). Now move bottom apex to bottom right of middle square, and area still stays the same. But you’ve ended up with triangle half the middle square so area 10.