Happened right here too: thieves opened up man hole covers in city parks and took the wires. The city now has large boulders right over those man hole covers...
Euler was a master manipulator of formal expressions; don't think it bothered him very much whether, e.g., an infinite series converged or not. (Unfortunately don't remember a source for this offhand -- maybe a leftover impression from having read ET Bell's book long ago? I also don't know how reliable Bell is.)
Cauchy is the one who introduced rigor to calculus with the formalization of limits, including epsilons and deltas, a full century after Leibniz and half a century after Euler.
There's understandably been a focus on speed, but what I really like about Julia is being able to write clear code: it has a lot of the flexibility and expressiveness that I like in Lisps, but with better numerical libraries than most Lisps/Schemes, and I really like prototyping algorithms in it. To me (an applied mathematician) it is just a nice tool for thinking in. Not having to compromise too much on speed is a big bonus.
Unfortunately the NS/macOS version still needs work as far as I can tell. Even not fully featured it's still useful: I prefer reading PDF in xwidget-webkit than pdf-tools, and it's great to have Jupyter notebooks running inside a browser inside Emacs.
Where I live we still have a locally owned video rental store, though several years ago they put in a bar and now it's more a bar with a video section than a video store where you can get beer and watch movies. We do still rent when there's something we can't stream on one of the services we pay for; I much rather do that than give more $ to Amazon and the like.
It's weird when shops pivot. There was a record store in a neighboring village that went from vinyl to video game kiosks. Then the record store that became a candy store. Put couches in bookstores and people stop buying books. I guess they figure the rent is paid by benefactors. Then again, Barnes & Noble seems to have a partnership with Starbucks...
Bott is often quoted as saying "Evrey mathematician has a secret weapon. Mine is Morse theory." Every time I see his name I've tried to look up a source. Finally found one:
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