tokenadult

Thanks for sharing this particular Feynman lecture. The treatment here, using what are basically the Peano postulates to derive the field properties of the real numbers and then the basic structure of secondary school mathematics, follows the treatment of Landau's Grundlagen der Analysis (Foundations of Analysis), a concise book that Feynman was probably aware of as he presented his lecture. Feynman of course added a sense of excitement and wonder that makes this lecture charming to read. Such treatments of the foundations of secondary school mathematics are fairly commonplace in the better university textbooks of mathematics. I first learned of Landau's book in a discussion of mathematics education in a Usenet newsgroup back in the 1990s, and bought the German edition on the recommendation of Michael Spivak's famous textbook Calculus, which follows a similar approach (but starting from the field properties of real numbers taken as axioms). In those days, I'm pretty sure, the standard calculus textbook at Caltech, where Feynman taught, was Apostol's textbook, which starts a little bit differently but also takes a theorem-proof approach.

https://maa.org/press/maa-reviews/calculus-4

Contractual agreements are enforceable at law. That's what makes them contracts.

My user experience on several recent trips is that Google Maps showed me the exit number for the exit I would use next very prominently on top of the display (where it shows the direction of the next turn). Maybe that isn't rolled out consistently for all trips.

Further confirmation of the news that Post is open to all now.

https://post.news/article/2KkQM0Ou0VIvhpS0YB4RHFvANkc

Post is currently a progressive web app. There is no immediate plan to build dedicated mobile apps for Post.

To access Post on my desktop computer, I just any browser to navigate to Post [dot] news. It's just a website. I have stored cookies on one browser I use, and I typically start up that browser with Post as one default tab. I have another browser I use for testing websites that shows me what Post looks like to users who have never logged in.

https://post.news/

OP here. My apologies for the phrase "Twitter alternative" in the article title, which is NOT exactly Noam Bardin's vision for the Post startup.

I appreciate the comments here from HN users. I've hardly posted here in a long time, because in recent years I have posted mostly about politics, which is off-topic posting here on HN. A federated world of specialized online communities is an appealing idea, and I will be trying out the Fediverse as well. (A lifelong friend who is an infosec specialist has landed on a server about infosec, and that's probably where I will establish a lurker account, in the interest of being on a securely configured server.)

Information security in an online service is one of the features I look for, and why I prefer big, well invested commercial online services to home-brew solutions. I figure HN has enough back-end infrastructure to keep what data I share with HN safe, and Facebook does too. (One can dislike how Facebook allows advertisers to look at user data while still appreciating how Facebook keeps away certain kinds of criminal threat vectors.)

The user perception of the user experience ultimately decides what users think about online networks. Part of the user experience in any network is the other users. That's what I've long appreciated about HN. That's what I liked about Twitter as I took care to follow interesting people who post there. I'll see about the newest communities and who else is there, and decide based on my preferences as everyone else will.

Thanks again for the back-and-forth in the discussion here, which has been good food for thought.

The phrasing "Twitter alternative" is my fault in setting the title for the thread-opening post here. The "Twitter alternative" phrasing should not be attributed to the founder of Post.

I get the impression that the founder, Noam Bardin, DOESN'T think he's building a Twitter alternative but rather, in the beta welcome page's words, "a civil place to debate ideas; learn from experts, journalists, individual creators, and each other; converse freely; and have some fun. Many of today's ad-based platforms rely on capturing attention at any cost — sowing chaos in our society, amplifying the extremes, and muting the moderates. Post is designed to give the voice back to the sidelined majority; there are enough platforms for extremists, and we cannot relinquish the town square to them."

Twitter has never been quite like that. If the founder's vision succeeds, I might like Post very well indeed. In all such things, the proof is in the user experience as experienced by each user, but I think the goals sound good for Post.

I would start by largely imitating the courses that already exist in the country of Singapore. They are pretty good examples of international best practice, and they are available in English, the language of school instruction in Singapore.

https://www.singaporemath.com/Singapore_Math_s/331.htm

A good framework for looking at careers and figuring out if your best trade-off is to do your occupation as a direct way to make the world a better place or to make your living and then donate money to make the world a better place can be found in the book Doing Good Better: How Effective Altruism Can Help You Help Others, Do Work that Matters, and Make Smarter Choices about Giving Back by William MacAskill. In many ways, it is the best career planning advice I have ever seen in any book, and I'm applying for myself and encouraging my four children to use the same planning framework.

https://www.amazon.com/Doing-Good-Better-Effective-Altruism/...

"The mounds, which are easily visible on Google Earth, are not nests."

This sentence from the article kindly submitted here ignores that Google Earth imagery includes imagery taken from airplanes as well as from satellites. Statements that such-and-such an object (a classic example is the Great Wall of China) is visible from space, or from the Moon, go back to eras long before human space flight. Most such statements are wrong.

As other comments previous to mine have noted, various specialized imaging devices in satellites (or on airplanes) can have a higher resolution than human-eye vision. But the headline "are visible from space" is surely an exaggeration. Space flight has been going on since 1960s, but there has been no report of the termite mounds till now, it appears.

I hope there is further work on renewable aviation fuels, as vehicle fuels in general will be a big source of demand for fossil energy extraction for quite a while, and especially for aviation applications.

"Renewable energy in transport" report by IEA (.PDF)

https://www.iea.org/media/training/presentations/Day_2_Renew...

I like anything by John Stillwell about the history of mathematics. It's accessible (not QUITE as accessible as The Lady Tasting Tea) and interesting.

https://www.amazon.com/Elements-Mathematics-Euclid-John-Stil...

I know eminent IQ researchers back at the time who declined invitations to sign on to the Gottfredson consensus statement (with good reason, in my opinion). On the other hand, it is still a reasonably fair statement of a lot of the consensus among IQ researchers, but as you say now twenty years out of date. (I read the consensus statement right after it was published.)

Thanks for sharing that link. The underlying paper is (of course) better than the popular article kindly submitted to open the interesting discussion here. In particular, the paper makes clear its own methodological limitations.

Gottfredson's paper is a paper that I have read, and I see it is being used as the analytical framework for criticizing psychology textbooks. I do research for writing popular writings on psychology, so I have a whole bunch of introductory psychology textbooks in the office where I am typing this, and I have to agree that introductory psychology textbooks leave a LOT to be desired in representing the consensus of modern psychology research. That's true about research on human intelligence and true about any other psychology topic: the introductory textbooks only do a so-so job.

That said, one might wonder where to find good information about current psychology research. Sometimes there are review articles that update practitioners on current research, which are incidentally read by scientists in other disciplines. I'll note for the record that not all psychologist agree EITHER with the review article I will link here, but it is a good readable account of current issues in the psychological research on human intelligence and well worth a read for Hacker News participants who are curious about these issues. It refers to many of the most important papers in the field, most of which I have read over the last three decades.

Nisbett, R. E., Aronson, J., Blair, C., Dickens, W., Flynn, J., Halpern, D. F., & Turkheimer, E. (2012). Intelligence: New findings and theoretical developments. American Psychologist, 67, 130-159. doi:10.1037/a0026699

(Disclaimer: I have met many of the researchers on human intelligence, including Gottfredson, at professional conferences, but my views of what the overall research says and who has the best leads on open research questions are my own.)

http://people.virginia.edu/~ent3c/papers2/Articles%20for%20O...