31–40 of 77 posts
> Often brought up as an example are the topological notions of “open” and “closed” sets. It sounds as if they should be exclusive and exhaustive — surely a set that is open is not closed, and vice versa? — but no, there are sets that are neither open nor closed and other sets that are both For a rant on this see "Hitler Learns Topology" [1]. [1] https://www.youtube.com/watch?v=SyD4p8_y8Kw
I can see the point, but I don't think it's a problem as long as the concept is well-defined. It's only a matter of getting used to don't assume, for example, "open" and "closed" to be mutually exclusive. There are other fields that don't have the privilege of this formal setting: I expect the concept of "species" to be very important in biology, but there isn't a clear definition of that (yet) [0]. [0] https://en.wi…
The world is an endless adventure in ever-expanding tendrils of interest, if not gated by rote.
The function f(x)=1/x is continuous, but its graph is not connected. It's an interesting one to explain to people.
Earlier quoted context omitted.
Oh yes. I've a book on dynamic programming (Applied Dynamic Programming, Bellman + Dreyfus, seriously over my head unfortunately) which uses missionaries, cannibals and a boat to cross a river (page 97). The authors talk about M cannibals and N missionaries. Note again: he used the letter M for cannibals, not the missionaries, which I note start with that letter. And he could have called the cannibals C but, no. I li…
Ah yes, you reminded me. There was another piece of jargon I was trying to come up with that really stinks earlier, but I couldn't remember it. And that's what it was: dynamic programming . Terrible name: "Where did the name, dynamic programming, come from? The 1950s were not good years for mathematical research. We had a very interesting gentleman in Washington named Wilson. He was Secretary of Defense, and he actua…
But please allow me to disagree with you. The term programming/programme predate programming as we know it, and he was free to use it in the sense of 'scheduling', much like a radio or TV schedule. The dynamic also makes sense as the schedule (or whatever) picks its next state depending on a previous/simpler state (hence a 'stage' in multistage, though I can't understand his use of 'time-varying' here). I think it's ok.
I'd rather punch mathematicians who won't bracket over mathematicians who try and protect themselves and their work from over-powerful, deeply stupid people.
The Type I and Type II errors is especially hurtful to me: I am totally unable to remember which is which and each time I read an article containing them I think: well, I am probably going to get it wrong again but I cannot bother to check the definition one more time... who cares?