Today I Learned
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JorisL
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nsaspook said:[youtube vid]
Well we can close this thread now. Isn't going to get much better than this.
Danger
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Is that the pocket with the "hole" in it?edward said:Today I learned for the second time that I should not put a 9 volt battery in the same pocket as my keys.

Science Advisor
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Today I learned why x is universally the first symbol we reach for for an unknown or a variable - when any letter or printable sign would do as well.
Descartes had settled on start-of-alphabet letters for knowns and end-of-alphabet ones for unknowns. The printer was running short of z's and y's which are used in more French words than is x, and intelligently asked him whether it mattered whether he used one or the other. (He had surely never seen a text like it, for nor had anyone else). Descartes replied he could replace all the z's with x's, and here we still are.
I say I didn't know this before, but I am not so sure I know it now. It is third-hand or so. I saw it reading just now Unknown Quantity (history of algebra) by John Derbyshire which I was given for Christmas a year or two ago. But Derbyshire quotes one Art Johnson for it, what the ultimate source is and how reliable I don't know.
But at least I learned a new story.:)
Descartes had settled on start-of-alphabet letters for knowns and end-of-alphabet ones for unknowns. The printer was running short of z's and y's which are used in more French words than is x, and intelligently asked him whether it mattered whether he used one or the other. (He had surely never seen a text like it, for nor had anyone else). Descartes replied he could replace all the z's with x's, and here we still are.
I say I didn't know this before, but I am not so sure I know it now. It is third-hand or so. I saw it reading just now Unknown Quantity (history of algebra) by John Derbyshire which I was given for Christmas a year or two ago. But Derbyshire quotes one Art Johnson for it, what the ultimate source is and how reliable I don't know.
But at least I learned a new story.:)
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DennisN
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Today I relearned the fundamentals of soldering. I tried desperately to resolder a connection but it simply did not work, I could not heat up the metal, and it seemed as if the heat incredibly effectively dissipated from the metal. But then, at last, I discovered that my soldering iron was not connected to the power supply. And I felt that well-known mixed feeling of relief and stupidity. Peace, at last, and heat, at last.
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Today I learned we've discovered around 1800 exoplanets!
Medicol
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Really, it is only 1700.Greg Bernhardt said:Today I learned we've discovered around 1800 exoplanets!
OmCheeto
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Today I learned the proper definition of "levitation". :)
At a sushi bar:
At a sushi bar:
Taco Bell Customer; "I'd like a couple of tacos".
Sushi bar serves them a plate of octopus.
Taco Bell Customer; "This isn't what I ordered".
Sushi bar person; "Um..., actually, it is".
Taco Bell Customer; "No it isn't. Tacos have crunchy shells, and are filled with cooked meat and stuff. This looks like raw octopus. Yuck!"
Sushi bar person; "Taco Bell is 3 blocks down, on the left hand side of the road".
Taco Bell Customer; "You're stupid"!
Sushi bar person; "Did you know that in Spanish, a "taco" is a rolled up piece of paper that you shove down the barrel of an old fashioned gun to keep the gunpowder and ball from rolling out"?
Taco Bell Customer; "You're mean"!
Sushi bar person; "Did you know, that in Serbian, "taco" means "thus""?
Taco Bell Customer; "Stop making fun of me"!
Sushi bar person; "But I'm just trying to help you learn".
Taco Bell Customer; "Learn! I came here for TACOS! I hate you".
...
Sushi bar serves them a plate of octopus.
Taco Bell Customer; "This isn't what I ordered".
Sushi bar person; "Um..., actually, it is".
Taco Bell Customer; "No it isn't. Tacos have crunchy shells, and are filled with cooked meat and stuff. This looks like raw octopus. Yuck!"
Sushi bar person; "Taco Bell is 3 blocks down, on the left hand side of the road".
Taco Bell Customer; "You're stupid"!
Sushi bar person; "Did you know that in Spanish, a "taco" is a rolled up piece of paper that you shove down the barrel of an old fashioned gun to keep the gunpowder and ball from rolling out"?
Taco Bell Customer; "You're mean"!
Sushi bar person; "Did you know, that in Serbian, "taco" means "thus""?
Taco Bell Customer; "Stop making fun of me"!
Sushi bar person; "But I'm just trying to help you learn".
Taco Bell Customer; "Learn! I came here for TACOS! I hate you".
...
TheDemx27
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Today I learned that a simple majority voting method is not the most "fair". http://zesty.ca/voting/sim/
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1853 to be exactMedicol said:Really, it is only 1700.
Danger
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OmCheeto said:At a sushi bar:
Taco Bell Customer; "I'd like a couple of tacos".
Sushi bar serves them a plate of octopus.
Taco Bell Customer; "This isn't what I ordered".
Sushi bar person; "Um..., actually, it is".
Taco Bell Customer; "No it isn't. Tacos have crunchy shells, and are filled with cooked meat and stuff. This looks like raw octopus. Yuck!"
Sushi bar person; "Taco Bell is 3 blocks down, on the left hand side of the road".
Taco Bell Customer; "You're stupid"!
Sushi bar person; "Did you know that in Spanish, a "taco" is a rolled up piece of paper that you shove down the barrel of an old fashioned gun to keep the gunpowder and ball from rolling out"?
Taco Bell Customer; "You're mean"!
Sushi bar person; "Did you know, that in Serbian, "taco" means "thus""?
Taco Bell Customer; "Stop making fun of me"!
Sushi bar person; "But I'm just trying to help you learn".
Taco Bell Customer; "Learn! I came here for TACOS! I hate you".
...

Reminds me of the time the Yanks came across the border (to the south of their origin; we were in Windsor, across the river from Detroit) with skis on top of the car when it was over 100° F. with about 99% humidity and asked us where the snow was. They were offended when we told them to turn around and go about 900 miles.
Mentor
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Last several days I spent learning how to convert a book written in OpenOffice to pdf (LaTeX), mobi (Sigil) and epub (Calibre). Ugly process. While I am not 100% ready yet, I think it is a beer time.
No, just exporting from OpenOffice is not a solution, quality that it produces is mediocre at best. I need a professionally looking product. If you are not sure about the content, at least make it look good ;)
No, just exporting from OpenOffice is not a solution, quality that it produces is mediocre at best. I need a professionally looking product. If you are not sure about the content, at least make it look good ;)
Danger
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I thought that you Poles were more like we Canucks; it's always a beer time.Borek said:I think it is a beer time.
That's why I always wear padded pants.Borek said:If you are not sure about the content, at least make it look good ;)

RonL
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Danger said:That's why I always wear padded pants.![]()
Do you know they now have hydraulic jacks to replace those pads? complete immunity from cold water and weather. oo):)
Danger
Gold Member
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Uh... no...RonL said:Do you know they now have hydraulic jacks to replace those pads?
Do I even want to know why you are aware of this?

jollyunclejoe
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Today I learned all about Sir Franklin's Arctic expedition, and now I can't close my eyes without seeing three frozen corpses swaying in front of my bed. Guess it's another all-nighter for me tonight. Sleep for knowledge = worthy trade off?
Danger
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Whoa, now! I just got finished with you in the other thread and now run across this...jollyunclejoe said:Today I learned all about Sir Franklin's Arctic expedition
So you're a fellow Canuck? Going by the avatar, along with your posts, I assume that you're in medicine and given this one in particular... pathologist? Maybe forensic anthropologist? Anyhow, try to have a nice sleep after the Pythons get through with you.

jollyunclejoe
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No, I'm from the States, and I'm afraid I do not work in medicine, pathology, or forensic anthropology, although all of the subjects I've just mentioned are interests of mine I suppose. Yes, the avatar is a bit misleading. It's actually a picture of Douglas Adams (I'm a huge admirer of his work as I know many others on this forum are). Once again, thank you, and I will try :). Today, I've also learned that Danger is Canadian.
Danger
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Me and the Wolverine; kindred spirits.jollyunclejoe said:I've also learned that Danger is Canadian.
I've never seen Adams with his mask on before. The "Guide" rules!
Hang on now! Why are you still here? You should be almost finished the first "Python" instalment by now.
jollyunclejoe
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It does rule, I couldn't agree more completely! I have in fact been watching episodes obediently, I'm just pausing the video whenever I receive reply notificationsDanger said:Me and the Wolverine; kindred spirits.
I've never seen Adams with his mask on before. The "Guide" rules!
Hang on now! Why are you still here? You should be almost finished the first "Python" instalment by now.
Danger
Gold Member
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Okay, then. I will not reply to you again after this for at least 12 hours. To bed, young man...
jollyunclejoe
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Fair enough, sleep well then. I'll provide a summary of how my night went in the morn.Danger said:Okay, then. I will not reply to you again after this for at least 12 hours. To bed, young man...
Danger
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One exception to the foregoing promise... this being it. I didn't mean that I am going to bed. I'm not, other than the fact that I'm sitting on my bed because it's also my couch. It becomes my bed when I lie down. I was referring to you trying to get at least a couple of nods after you've laughed yourself silly.
jollyunclejoe
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Fair enough once again, in that case, have a good sofa session. I shall return now to my howls of derisive laughter before the now almost inevitable sleep. Cheerio thenDanger said:One exception to the foregoing promise... this being it. I didn't mean that I am going to bed. I'm not, other than the fact that I'm sitting on my bed because it's also my couch. It becomes my bed when I lie down. I was referring to you trying to get at least a couple of nods after you've laughed yourself silly.
Medicol
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I learned that long before you did. Now I have to learn who that is.jollyunclejoe said:... Today, I've also learned that Danger is Canadian.
nitsuj
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Today I learned that Weezer did a cover of The Band's "The Weight". ...and it sounds better 
Though exactly the same rhythmically, imo it's "done" better
Wait that doesn't count as an "I learned today"

Though exactly the same rhythmically, imo it's "done" better
Wait that doesn't count as an "I learned today"
Danger
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I'm pretty sure that nobody cares about that any more. This has turned into a "strange truths" or "aha moments" sort of thread as opposed to one about something that you have literally learned today. I learned my Alka-Seltzer lesson more than 2 years ago, but that didn't stop me from posting it here as if it were new.nitsuj said:Wait that doesn't count as an "I learned today"
The fiinal determination is up to Greg, of course.
Mentor
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TIL that gravitational lensing about a black hole is more complicated that a funhouse mirror with photons orbitting the black in all sorts of bizarre ways before they get to your eyes. (Science of Interstellar Chapter 9) and its even more complicated for spinning black holes.
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