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I didn’t know Dark Souls servers were still up. Was invaded after 30 hours of playing. Poor guy took quite many fireballs…

This week I’m listening some lectures on graph colorings. We’re done with the planar ones and now going to other surfaces. First examples were on the torus. Tori are also known as JRPG world maps (and so this pure math lecture _can_ be applied to useful things).

Any algorithmic task can be sabotaged to create real-life versions of a hostile environment. This can be done by turning it into a game, which can be studied by know techniques. Thus, in Clausewitz’ immortal phrasing, game theory is “algorithmics pursued by other means”. — van Benthem, “An Essay on Sabotage and Obstruction “

This 1000% more true today in there era of "Just throw it into an AI/ML black box and use the answer" than in 1979. #programming #ethics…

Today I’m grading the first report for a class I’m TAing this semester. I’m happy thar I receive all reports on Google Classroom, but most are bad quality photos of bad handwriting…

So many bad takes in this article. Yes, students are tired, yes they are burnt out, yes their mental health and, consequently, their learning is suffering. But to lay the blame at the feet of online learning is false. Students didn't do poorly because of online learning (and what occurred over the past 2 years is not online learning but emergency remote learning - there is a huge difference). Perhaps they have been struggling to do well because, oh idk, GLOBAL PANDEMIC?

What we call mathematics

Some thoughts about the subject we call mathematics and how that does - and doesn't - change.

Love how completely banjaxed so many online services are by the idea that you might now be living in a different country from the one where you first signed up...

By the law of excluded middle, either ‘A is B’ or ‘A is not B’ must be true. Hence either “the present king of France is bald” or “the present king of France is not bald” must be true. Yet if we enumerated the things that are bald, and then the things which are not bald, we should not find the present king of France in either list. Hegelians, who love a synthesis, will probably conclude that he wears a wig. — B. Russell

@SylviaFysica there's a pair of papers by Joe Halpern and Francis Chu called "Great Expectations" parts 1 and 2. Part 2 has a pub date 4 years before part 1.

Found this quote from Quine on van Benthem’s Manual of Intensional Logic. I’ve been reading quite a lot no modal logic, so most authors don’t agree with Quine (essentially, some things are necessarily P have two readings: \(\forall x.\Box P(x)\) or \(\Box \forall x.P(x)\), that is, ‘de re’ or ‘de dicto’). I really need to take some time to read Quine’s texts.

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Mathematicians are necessarily rational, but not necessarily bipeds. Cyclists are necessarily bipeds, but not necessarily rational. But then, what about mathematician cyclist Paul K. Zwier: he is both necessarily rational and not necessarily rational… and his motion is as contradictory as his mind? — Quine

@erou Sometimes when you can't solve a problem it's worth going back to the definitions.


* State the definition;
* Give me three simple examples;
* Give me two simple non-examples.


And yes, people ignore this advice.

(Young) Math students of the world, when you don't have any idea of how to solve a problem, you can try to:

- make a drawing in order to better understand what's happening

- try to solve a simpler instance of the problem in order to see if what you are trying to prove is indeed true, why, and what could possibly be wrong in the complicated case

These are very easy advises that essentially nobody follows 🙄

Mathematics is not about numbers, equations, computations, or algorithms: it is about understanding. -- William Paul Thurston, American mathematician

Mixed numbers don't exist in some countries. If you use them in written form, some people may not understand them at all.

Every Salami has two ends
Article by Bobo Hua and Florentin Münch
In collections: Attention-grabbing titles, Food
A salami is a connected, locally finite, weighted graph with non-negative Ollivier Ricci curvature and at least two ends of infinite volume. We show that every salami has exactly two ends and no vertices with positive curvature. We moreover show that every salami is recurrent and admits...
Entry: read.somethingorotherwhatever.

… in order to be able to set a limit to thought, we should have to find both sides of the limit thinkable (i.e., we should be able to think what cannot be thought). — Wittgenstein

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