Street-Fighting Mathematics - <AUTHOR> https://mitpress.mit.edu/books/street-fighting-mathematics <comment><USER2> For the people who did not notice, in the "Open Access" tab you can download the PDF of the whole book legally and for free.

There is also a second book by the same author which is a bit harder and more comprehensive, and also open access:

[https://mitpress.mit.edu/books/art-insight-science-and- engin...](https://mitpress.mit.edu/books/art-insight-science-and-engineering)

<comment><USER3> Also available as part of the MIT OCW[0]

[0] [https://ocw.mit.edu/courses/mathematics/18-098-street- fighti...](https://ocw.mit.edu/courses/mathematics/18-098-street-fighting- mathematics-january-iap-2008/readings/)

<comment><USER4> I took this course during a January term. It was great fun and Sanjoy was a great teacher, with tons of energy and enthusiasm.

</comment></comment></comment><comment><USER5> _" Mahajan describes six tools: dimensional analysis, easy cases, lumping, picture proofs, successive approximation, and reasoning by analogy. Illustrating each tool with numerous examples, he carefully separates the tool—the general principle—from the particular application so that the reader can most easily grasp the tool itself to use on problems of particular interest. Street-Fighting Mathematics grew out of a short course taught by the author at MIT"_

That short course looks like its still available on edx - though it's archived - I seem to be able to access the material.

[https://www.edx.org/course/street-fighting- math](https://www.edx.org/course/street-fighting-math)

<comment><USER6> The content looks quite interesting for a mathematician too—so I'm sorry that the advertising needs to be antagonising.

But even _Keep the Aspidistra Flying_ was basically mutilated by circumstance [1] and it's still a great book. So, I'll take the insults towards mathematicians with humour and actually read some of it—I often switch between grumpy rigour to applicative speed. We all need to earn an income.

[1] [https://en.wikipedia.org/wiki/Keep_the_Aspidistra_Flying#Lit...](https://en.wikipedia.org/wiki/Keep_the_Aspidistra_Flying#Literary_significance_and_criticism)

Edit: Just to be clear, my comment on mathematicians is not on your quote, but this quote from OP's post:

> an antidote to mathematical rigor mortis

<comment><USER7> How on earth is any of the advertising antagonizing? I had to read through the course page twice to look for anything remotely resembling a criticism and came up blank.

If it is the quote you added to the bottom of your comment, my question still stands. That isn't an insult to anyone (certainly not mathematicians) but rather a comment that many people freeze up when it comes to mathematics (at least that was my interpretation).

<comment><USER6> There is a somewhat common attitude towards abstract mathematics that its preciseness is something of a bother to people and that it requires some kind of "cure".

Immanuel Kant wrote about it [1] and many engineers have a varying degree of animosity towards pure mathematics. So, in the book's description they say this:

 _This engaging book is an antidote to the rigor mortis brought on by too much mathematical rigor, teaching us how to guess answers without needing a proof or an exact calculation._

I don't like the advertising, or the description if you will, as it basically tries to discount rigour. One can simply say it's an _addition_ to the usual rigour of mathematics for the sake of daily street fighting style problem solving. The way they state it, however, it sounds like they are saying that rigorous math is not necessary.

My reference to George Orwell is simply that when he wrote _Keep the Aspidistra Flying_ his publishers made him write a lot of things he didn't want to write, and they even specified the amount of words the books needed to have (which is is somewhat understandable, but limiting still).

[1] [https://en.wikipedia.org/wiki/Critique_of_Pure_Reason](https://en.wikipedia.org/wiki/Critique_of_Pure_Reason). However, note that this is about _metaphysics_ and one can argue that pure mathematics is not what he was critisising and that his work doesn't directly try to disprove the use of axioms, without which mathematics cannot exist.

</comment></comment></comment></comment><comment><USER8> I discovered Prof Mahajan through his "Teaching College-Level Science and Engineering" course on MIT OCW. I must have watched it six times during graduate school. He also has an OCW course based on this book.

[http://web.mit.edu/sanjoy/www/](http://web.mit.edu/sanjoy/www/)

</comment><comment><USER9> Stanford has an excellent physics course, "Back-of-the-Envelope Physics," based on Mahajan's work. On the first day we worked out how much to feed a baby every day assuming they are spherical heat emitters of radius 1 meter... (also, you got points off the problem sets if your answers were _too_ precise).

<comment><USER10> That's a big baby.

<comment><USER11> Calculations are so much easier when it's a unit circle/sphere.

Here's my favorite trick: the radians of an angle in a unit circle is equal to the length of the arc of that unit circle.

<comment><USER10> That's not exactly a trick. It's the point of the definition.

<comment><USER11> I think you're being needlessly pedantic. Just because it's easy to derive doesn't mean it's immediately obvious. I only realized it when I watched a 3Brown1Blue video where he pointed it out as interesting property of the unit circle. That alone tells me its not that obvious to many.

<comment><USER12> You did not get parents comment. Its not a derivation its a definition.

<comment><USER11> Personally, that again sounds like a very pedantic and obvious point to me. However, I could be wrong so feel free to break down your point further.

My interpretation is that I think you guys are missing the fact that the intent of my original comment is in the context approximations, from which you can see the use of the 'trick' is correct.

To break it down a little further: the trick I am referring to is in practice it's often convenient to scale approximations so that you can use the unit circle for calculations, since you can use the radians as a measurement of arc length. If it's not a unit circle, the angle != arc length, so that convenience is lost.

<comment><USER12> > Just because it's _easy to derive_ doesn't mean it's immediately obvious

is what I was responding to. My point is this -- there is _no_ derivation happening there. If it was pedantic, obvious and simple to you as you claim, I wonder why you claimed that it was a derivation.

To you the distinction between a definition and a derivation might be a _pedantic_ one, I have doubts on whether that is an universal or even an useful position to have.

</comment></comment></comment></comment></comment></comment></comment></comment><comment><USER13> I have a copy of this book and haven't read it. I keep fearing my background won't be strong enough. I struggle with some high school math (I did get a math degree many years ago but haven't kept up with even basic algebra, and it shows). This book's preface says it complements How to Solve It, another book I've been scared to crack open.

Nonetheless the thinness of the book and the foreword about applications and real world math are very promising. Maybe I should try it out. Any thoughts from someone who has read it?

<comment><USER14> It is great and the math is easy. There are a couple clever tricks ( like how to calculate pi), but nothing beyond high school math.

<comment><USER13> thanks :)

</comment></comment></comment><comment><USER15> Sanjoy's graduate thesis covers some of the same material, and is also good reading:

[https://thesis.library.caltech.edu/5338/](https://thesis.library.caltech.edu/5338/)

</comment><comment><USER16> I feel that _to some extent_ this should be similar to estimation questions that consultants face in their interviews. Questions like:

\- How many gas stations are there in Paris?

\- How much savings does the leading bank of the USA have?

\- Estimate the population of Indonesia (to someone who is not that familiar with Asia).

It's probably a great deal more complicated than these type of questions. But if there is a course like this and a student still feels as overwhelmed by these type of questions, then I feel the title should be updated accordingly.

The reason I'm also mentioning this is because I'm curious if anyone did both and can attest to whether one does get better at estimation questions like the one I outlined. If so, I just might want to take this course, as I'd like a deeper exploration on the topic than just consultant interview estimation questions.

<comment><USER17> fwiw the types of questions you mention are often refered to as Fermi problems, after the famous physicist.

[https://en.wikipedia.org/wiki/Fermi_problem](https://en.wikipedia.org/wiki/Fermi_problem)

<comment><USER16> Awesome! I'll take a look at that.

FWIW: it was worth quite a bit :)

</comment></comment></comment><comment><USER18> I took Sanjoy's Bayesian inference course at Olin College of Engineering. One of the few courses during my undergrad experience that just gave me pure joy and excitement. He's one of those people who can explain seemingly complex concepts to a 6 years old.

</comment><comment><USER19> This is an awesome book - its techniques have served me well in the years since reading it. Its small size and high information density make it a good carry-on for flights and long bus or train journeys.

</comment><comment><USER20> On a side note, does anyone know why certain books are restricted for sale only in certain subcontinents? For example this book is "Not for sale on the Indian subcontinent."

<comment><USER21> As far as I can tell, textbook publishers practice price discrimination so that they can sell less expensive versions of the same book in markets where profit is maximized at a different price. Retailers are only permitted to sell the appropriate version in the appropriate market.

Personally I have seen many textbooks available in the US/Canada version and Indian Subcontinent version (generally the same text, often for sale at <25% the price). My guess is that it's common to see India in particular because there is a large market for English-language textbooks there.

<comment><USER20> It falls along the same line of argument that big Journal Publishing groups like Elsevier and Springer do the same when giving subscriptions to countries across Europe vs Africa. I heard this in a talk from a former director of Radboud University in Netherlands who is now spearheading the Open Science movement in Europe.

</comment></comment></comment><comment><USER22> Ha, I misread the title as "Street-Fighting Mathematicians" and expected something about characters such as Galois ([https://en.wikipedia.org/wiki/%C3%89variste_Galois](https://en.wikipedia.org/wiki/%C3%89variste_Galois))

<comment><USER23> I was expecting a hard data approach to a style of unarmed combat. Wouldn't even be the first time something like that's been written: [https://www.amazon.ca/dp/1904658849?tag=duc12-20&linkCode=og...](https://www.amazon.ca/dp/1904658849?tag=duc12-20&linkCode=ogi&th=1&psc=1)

</comment></comment><comment><USER24> A beautiful book. I have all my students read it and I use its ideas every day in research.

</comment><comment><USER25> >> Not for sale on the Indian subcontinent.

huh?

<comment><USER26> I don't know if it is the case for this book, but many text books have vastly cheaper versions that are printed in India. Usually they are on much thinner paper. (I saw these during postgrad when some of the international students would bring texts from their home country.)

<comment><USER27> Could they have been pirating the books? In my home country (Turkey), there were alternative sellers (basically photocopiers) who made pirate copies of books (usually on much thinner paper and washed out colors) and sold them. They were exactly like bookstores and they'd have the books you needed in stock. They usually sold textbooks for 1/10th of the price.

<comment><USER28> Pretty sure it wasn't piracy. For instance see this[0] book (not affiliated), at the bottom left it says "Restricted! For sale only in India, Bangladesh, Nepal, Pakistan, Sri Lanka & Bhutan"

[0] [https://www.amazon.in/Abstract-Algebra-3ed-David- Dummit/dp/8...](https://www.amazon.in/Abstract-Algebra-3ed-David- Dummit/dp/8126532289/ref=sr_1_7?dchild=1&keywords=abstract+algebra&qid=1593094249&sr=8-7)

</comment></comment></comment></comment><comment><USER29> "Mahajan describes six tools: dimensional analysis, easy cases, lumping, picture proofs, successive approximation, and reasoning by analogy."

Reasoning by analogy sounds dodgy to me.

<comment><USER8> Dodgy how?

I've always found that it's difficult to get a student to even venture a guess about the answer to a problem. If they do make a guess then they probably have a mental model about how the situation should work... and then teaching becomes easy: either their model is good or it needs tweaking.

You gotta have the confidence to be wrong.

<comment><USER29> Using analogy to teach people something new makes sense and it's done all the time with positive effect.

But using an analogy to infer something that hasn't been observed? Unless the analogy is very close to the subject, it doesn't make much sense to me.

</comment></comment></comment><comment><USER30> I was actually expecting a book that explains real street fighting with mathematics (like kinetics of certain moves, optimizing impact on the opponent, etc.). I am a bit disappointed after reading the abstract...

<comment> codemonkey-zeta I've learned from acquaintances who grew up in "tough" places, where street fights are more common, that violence is more about social posturing than it is about the actual fighting. In these places one's reputation can be protection. If everyone knows Bob will escalate situations to a physical fight, then few people will confront Bob. I've heard it's analogous to mutually assured destruction, where the "crazier", more inclined toward violence an individual is, the less likely it is they will end up in street fights.

I imagine if you wanted to study fighting in a mathematical way, you would want to study experts. MMA fighters, boxers, Muay Thai fighters all optimize their bodies and technique toward effective fighting. I bet there would be interesting science/math there, but I doubt street fighting would actually yield much insight.

<comment><USER31> Rory Miller calls the most common social posturing "the Monkey Dance."

[http://chirontraining.blogspot.com/2013/03/cofv8-monkey- danc...](http://chirontraining.blogspot.com/2013/03/cofv8-monkey-dance.html)

related discussion: [https://news.ycombinator.com/item?id=23429390](https://news.ycombinator.com/item?id=23429390)

(to reply directly: leverage is useful, mixed game strategies are useful, beyond that I can't think of other applicable theories. Miller points out that non-posturing violence is usually as unfair as possible, so maybe big-O notation?)</comment></comment></comment>


Announcing Wolfram Programming Lab - <AUTHOR> http://blog.wolfram.com/2016/01/19/announcing-wolfram-programming-lab/ <comment><USER3> I am not sure Wolfram Research realize what they have.

If they would make their stack FOSS they would be absolute heroes and shape the future of applied math and computation software with a historic impact. Otherwise they will fade away, when other interfaces (Jupyter & Co.) catch up and/or surpass it in its capabilities. More and more people will just not accept the closed nature as it inherently contradicts with the idea of exploration.

There are basically 3 scenarios:

\- they go FOSS now: best outcome for people and Wolfram

\- they go FOSS later: good outcome for people, more difficult for Wolfram, as they lose developers/community

\- the don't go FOSS (or not in near future): Wolfram SW won't be used anymore as open alternatives surpass it. People won't care.

Even Microsoft got it.

<comment><USER4> I don't really see sympy and the like surpassing Mathematica. Even maple is kinda having trouble. If when I'm buying Mathematica I'm paying for a proper implementation of the risch (integration) algorithm, it will have been money well spent.

<comment><USER5> Doesn't Maxima [0] have a proper implementation of the Risch algorithm already?

[0] [http://maxima.sourceforge.net/](http://maxima.sourceforge.net/)

<comment><USER6> There is no complete implementation of the Risch algorithm. None of the implementations fully implement the algebraic case. Besides, the Risch algorithm doesn't solve all symbolic integration problems in practice:

* Even when it succeeds, it doesn't necessarily give you the simplest possible form of the solution.

* It is concerned with elementary functions, but real-world problem often involve non-elementary functions (like Bessel and hypergeometric functions). You can extend the Risch algorithm to work with such functions, but this is complicated.

* It doesn't allow computing parametric answers for common parametric families of integrals (this needs to be done using heuristics and lookup tables).

* It doesn't give you an algorithm for definite integration, except in simple cases. Even with proper definite integrals, you need to be extremely careful with branch cuts when applying the fundamental theorem of calculus. For improper definite integrals, systems like Mathematica generally try to go via convolutions of Meijer G-functions, using huge lookup tables and simplification heuristics.

* Even more fundamentally, the Risch algorithm (and symbolic integration more generally) puts heavy demands on the underlying symbolic computation engine. In particular, it depends on the ability to decide whether an expression is equivalent to zero, which in fact is an undecidable problem, and this strictly speaking makes the Risch "algorithm" a non-algorithm (though it is a proper algorithm when restricted to a ground field where zero testing is effective, such as Q).

<comment><USER5> I can only say that I am very impressed by the knowledge you are displaying about the Risch algorithm and symbolic integration. If I may ask, what is your background and how did you learn about them so deeply?

<comment><USER6> PhD in symbolic computation (RISC). Symbolic integration is not my field of research, though, and I don't really know anything beyond the basics (covered in courses on computer algebra). Passively attended plenty of seminars and conference talks on symbolic integration, though, and for a couple of years, I did share office with Clemens Raab who is one of the experts on the Risch algorithm.

<comment><USER5> I am working on a project that requires symbolic computation, which I am learning a bit by myself. For now I can manage, but could I get in touch with you in case I would need some advice about that? My email is in my profile (thanks!).

</comment></comment></comment></comment></comment></comment></comment><comment><USER7> I absolutely hate Wolfram's online workbook UI. No matter how careful I am I end up breaking it in so many ways. Delete that image of a horse? Too bad, have to refresh the page to get it back. Click enter incorrectly? That new line can never be deleted now. Want to format your document at all? Good luck.

I subscribed to their online offering when it originally came out, but immediately canceled because the UI is just so far behind its desktop competitors, like Maple, and even Matlab. I want to support this software, it has great potential, but they need to sit down and really rethink how it's put together and delivered to the user.

<comment><USER8> Maple makes me sad. They had an amazingly effective streamlined GUI circa 2000, a native Windows app which launched significantly faster than the built- in Microsoft calculator tool, and then felt like an upgraded terminal-style REPL with all of math at your fingertips. It had capable plotting with nice embedded graphics, great built in documentation with fast search, etc. It was rock solid, I don't think I crashed it once. As a high school student, it was an amazing tool for me.

Then they decided to hop on the Java bandwagon, and rewrote their whole UI using some kind of cross-platform Java GUI toolkit. App startup time went from like a tenth of a second to like 30 seconds (at least, that was my subjective impression at the time). Every part of the GUI was laggy and glitchy, it crashed regularly, the documentation was reorganized and much more confusing, etc.

The big-ticket feature additions which supposedly justified the rewrite were some gimmicky stuff for writing formulas in a more standard-math-typography way instead of as plain text, plus some related handwriting recognition thingy, but this ended up being slow, confusing, and ineffective, and cluttering up the rest of the interface.

<comment><USER9> I used a version of Maple that shipped with both the Java GUI and the native one. It was amazing how much faster the native GUI started and ran.

This was before I learned "real" programming, so I actually stuck with the Java GUI to get the pretty-printed math formula editor. Still, maybe that experience caused me to avoid writing Java programs later on...

<comment><USER10> However many Java desktop applications are bad, mainly because developers don't care.

\- No setting of the platform's L&F

\- Everything is done on the main thread

\- No care is taken about how to write GC friendly code and data structures

\- No attention to eye candy

It is like having Assembly developers cry at the shitty performance of C compilers in the early 80's and blame the language.

</comment></comment></comment></comment><comment><USER11> As an experienced developer, I surprisingly enjoyed progressing through Wolfram's book for beginners. (I used Mathematica, not their online UI.) In particular:

\+ Making instant web apps and APIs just by specifying two functions -- "front-end" and "back-end".

\+ Easily creating impressive-looking programmatic 2D and 3D graphics and sounds.

\+ Innovative idea making visible graphics and colors as arguments and outputs of functions.

\+ "Knowledgebase" of facts accessible using natural language. (Though, this was often slow due to server calls.)

My main critique of Mathematica is that it is the epitome of a kitchen sink library. There is an overwhelming number of functions for every possible thing. So, it is often not feasible to know what is offered without a lot of reading. (In fact, Wolfram even states this in his book.)

This is the real problem with their "knowledgebase". I would love to enter any natural-language query and get an answer, but in reality I need to check their list of supported areas and know the seemingly arbitrary list of facts about each area. To really make this useful, Wolfram has to figure out how to make it work without requiring me to be so knowledgeable about what it contains a priori.

Also, having such a large standard library makes the language very "flashy". It is indeed impressive and inspiring to create a sphere or musical piece in one line of code. However, real programs end up being much larger. In practical programs, Mathematica's functional syntax results in long unwieldy statements with forced formatting. This is occasionally impressive, but it is just as often hard to decipher.

<comment><USER12> I don't really get the complains about a kitchen sink of predefined functions, or the functional syntax. You can always fall back on defining a function yourself. (And with the amazing documentation and Google, it's quite easy to find most functions anyways.) Likewise, you can always use C++-style syntax for defining functions, for loops, etc.

Mathematica has plenty of problems, like it's extreme slowness for things that should be comiled, and awkward reference passing, but the ones you've pointed out don't really make sense to me.

<comment><USER13> > I don't really get the complains about a kitchen sink of predefined > functions

If you're running it locally, there's a very practical reason to complain: between Wolfram 7 and 8, the application bundle size went from 29 MB to 2.65 GB. That's not a typo.

<comment><USER14> About 70% of storage used by the latest version 10.3.1 is the documentation, for what that's worth (maybe nothing).

<comment><USER15> This is true for lots of programs. Try installing TeXLive or a similar LaTeX distribution from a package manager. Usually it pulls in a *-docs package that takes up well more than half of the download.

<comment><USER13> To be fair, though, it is very easy to customise TeXLive so that it _doesn 't_ do this; whereas, as far as I know, Mathematica offers no such option. To be sure, you can delete it afterwards, but I'm not sure how gracefully Mathematica deals with that; whereas TeXLive, for example, gracefully deals with incremental upgrades from a very basic installation. (I know, because that's exactly how I run it on my tiny SSD. My current installation is well under 1 GB.)

</comment></comment></comment></comment></comment></comment><comment><USER16> If you'd like a similar experience without being tied to a proprietary language and where the skills you develop can later be applied to other fields, I'd like to recommend our [https://tonicdev.com](https://tonicdev.com) .

It uses JavaScript (support for node 0.10 through 5), and instead of being one giant library made by one company, connects you to every version of every package on npm (that's 200,000+ libraries!). Anytime something is published on npm, it immediately becomes available on tonic, allowing you to work with the "global standard library". If you use something like D3, you can do math visualizations: [https://tonicdev.com/tonic/d3-example-from- beaker](https://tonicdev.com/tonic/d3-example-from-beaker) . Alternatively, you can use async and await to play with APIs: [https://tonicdev.com/capicue/iss/4.0.0](https://tonicdev.com/capicue/iss/4.0.0) . When you're done, you can hit download and run it on your own computer using node.

</comment><comment><USER17> Unrelated to the topic at hand but I browsed their site and found this gem...marketing might want to think about replacing that customer story:

[http://www.wolfram.com/mathematica/customer- stories/predicti...](http://www.wolfram.com/mathematica/customer- stories/predicting-mortgage-stability-with-mathematica.html)

"""Fannie Mae financial economist Bernard Gress is taking an innovative approach to predicting the stability of mortgages. He's using Wolfram technologies [...]"""

</comment><comment><USER18> My son is only 2 but I hope to pass on to him my love of maths, electronics and programming in an interactive way. This is why, for example I've been getting to grips with the raspberry pi and keeping tabs on the whole 'computer based math' movement. While I understand the background issues some HNers have with Wolfram I'm cheering on any efforts (including this new Wolfram Labs announcement) that may spark my son's interest and aid his future education.

<comment><USER19> check out www.jasymchat.com, not Wolfram but students love it:)

<comment><USER15> If you want to promote your own work and avoid the downvotes, now would be a good time to do a Show HN.

</comment></comment></comment><comment><USER20> Does this cost money..? I remember when the iOS app came out for the computational engine. For $50. I'm sure that was a long since rued decision to price it like that, but I still have this odd feeling about Wolfram doing this fancy stuff but trying to spin a big chunk o dough for it. (Not that it's a bad thing but I don't see cost talked about here compared to their other products?)

</comment><comment><USER21> Mathematica/Wolfram is probably the closest real-world implementation to Bret Victor's "kill math" vision of experiential programming.

</comment><comment><USER22> >Wolfram Programming Lab is something that's uniquely made possible by the Wolfram Language. Because it's only with the whole knowledge-based programming approach—and all the technology we've built—that one gets to the point where simple code can routinely do really interesting and compelling things.

Translating out of Wolfram-ese:

"simple code doing interesting things" -> expressiveness

"knowledge-based programming" -> lots of libraries

"uniquely made possible by the Wolfram Language" -> we have the best libraries, and therefore the most expressive language

Stephen Wolfram is a font of interesting ideas that deserve attention. He really is an intelligent and perceptive guy. The problem is he's so arrogant that he _consistently_ ignores (or, when he does acknowledge it, belittles) what others have done. I find myself unable to trust anything he writes or does because it's always filtered through the lens of his own brilliance - <USER2> intuitively expect that such a person will ignore serious problems with their own work because it's a threat to their ego.

I think we should look very carefully at his ideas, work out what they _actually_ are (instead of what he thinks they are because he's not a reliable source) and steal them.

</comment><comment><USER23> Every time I see something with Wolfram Language, I'm fairly impressed with how powerful it seems.

But then I wonder, is that just because I see people who are skilled in the art or is it intrinsic to the language? If it is so powerful, how come I don't see more of it being used? Is this just because it runs on a closed system? So does Matlab, but at least in my experience Matlab seems more widely used, why is that?

<comment><USER24> You can't really compare MATLAB and Mathematica. Mathematica excels at symbolic computation whereas MATLAB is primarily geared towards numerical analysis and scientific computing. You could code numerical things in Mathematica, but you'll get poor performance compared to MATLAB. Similarly, MATLAB does have a symbolic toolbox, but it pales in comparison to the extensiveness of Mathematica. Numerical and scientific computing work is generally more useful in industry than anything you would do with symbolic computation (e.g. you wouldn't analytically solve a sophisticated PDE so you would use numerics), so that explains why MATLAB seems more prevalent. As for your first question, I would say that Mathematica definitely has a lot of power built in. I know a few researchers (myself included) who have used Mathematica in some really cool ways only knowing the basics, which I think is a huge audience for Wolfram. With that said, there are definitely many power users who are probably doing greater things with the language.

<comment><USER14> > You could code numerical things in Mathematica, but you'll get poor > performance compared to MATLAB.

Yes and no. MATLAB and Mathematica have access to the same BLAS libraries. If you're using packed arrays in Mathematica, you can expect similar performance for many pure numeric things. Mathematica is missing some of the higher level primitives, there's no built-in function that corresponds to DGEMM, as a random example.

Another weakness is that there's only a handful of packed array types, for a 64-bit system, you get tensors composed of doubles, signed 64-bit ints, and complex numbers; no bool arrays, no unsigned 32-bit or 16-bit, no enum or factor arrays. Now this is purely a performance thing -- you can make tensors/arrays containing anything you want, but their contents just won't be 'packed' into a contiguous region of memory, instead they'll be arrays of pointers to other memory on the heap. Such arrays are slower to work with, much less memory efficient, harder to pass over an FFI, etc.

There's also a lack of fast workhorse-ish functions involving tensors, so there isn't a way to broadcast a condition (say 4 <= x <= 10) onto an input matrix to get a 'mask matrix' as is so common in MATLAB and R and so on, and one of their secrets to writing fastish code in a interpreted language.

On the other hand, you can deal with ordinary lists (and Associations) that contain arbitrary types (as with any dynamically typed language), which makes many kinds of algorithmic work very straightforward. After all, not everything is best represented as an n-tensor of reals or ints or bools! But if your lists _do_ happen to be homogeneous lists of ints or reals (of any rank), they will usually end up being stored more efficiently as mentioned above, a process that is, for better or worse, totally invisible unless you know about Developer/PackedArrayQ.

There is also Compile ([https://reference.wolfram.com/language/ref/Compile.html?q=Co...](https://reference.wolfram.com/language/ref/Compile.html?q=Compile)) which still has a fairly limited type system, but will still let you bypass large amounts of interpreter overhead when you need to do something performance critical.

> you wouldn't analytically solve a sophisticated PDE so you would use > numerics

The whole analytic/numerical distinction really isn't true anymore (e.g. [https://reference.wolfram.com/language/ref/NDSolve.html](https://reference.wolfram.com/language/ref/NDSolve.html), [https://reference.wolfram.com/language/FEMDocumentation/tuto...](https://reference.wolfram.com/language/FEMDocumentation/tutorial/FiniteElementProgramming.html)).

> so that explains why MATLAB seems more prevalent.

I think the explanation lies more with MATLAB having exactly the right features (or the right toolboxes) at the right time to fill niches in thousands of engineering and research labs. If you're running a lab, and that postdoc who wrote the code driving your instrument has long since left, there is very little reason to embrace a new language, even if it has caught up in various ways, and especially if that new language isn't tailored exactly to what you are doing, and would prefer you to use some strange thing called "functional programming", etc.

</comment></comment></comment><comment><USER25> Up to FIVE FILES! OMG!

I love Mathematica and use it at least once a week. But these "free" versions are nothing but your first hit. And the Wolfram Language is not something you're going to figure out in the course of an afternoon with five notebooks.

</comment><comment><USER26> This is awesome, but man are they are ton of different programming languages for the purpose of learning now. Most beginners are going to be confused on just which one to pick.

Best to Wolfram. Lets see if this can become the pack leader.

</comment><comment><USER27> Two questions:

A) Can I run my programs locally without connecting to the cloud? B) Can I dynamically embed generated graphs on my own site, instead of using the Wolfram Cloud to host it?

<comment><USER28> A) Yes, if you buy Mathematica. B) Sure, but I think the user needs to install a browser plugin.

<comment><USER29> B) not anymore

</comment></comment></comment><comment><USER30> Partially related: Wolfram Knowledge Base: [https://www.wolfram.com/knowledgebase/](https://www.wolfram.com/knowledgebase/)

</comment><comment><USER31> Massive egos aside, it's hard to think of a successful software company that is more anti-freedom than Wolfram. While I think all software should respect users' freedom, I recognize Apple, Microsoft, Oracle, and Adobe have all made at least some meaningful contributions to free software.

<comment><USER21> This comment comes off as shrill, without an explanation of what "freedom" means here, and why it is important.

Mathematica positions itself as a mathematical appliance, like a fridge or an oven or a car, none of which are generally running free software.

<comment><USER32> > Mathematica positions itself as a mathematical appliance, like a fridge or > an oven or a car, none of which are generally running free software.

And that is why there are Linux gurus that will invest lots of time to get GNU/Linux run on their fridge - because there _are_ people who will not accept this status quo.</comment></comment></comment>


Once considered a boon to democracy, social media looks like its nemesis - <AUTHOR> https://www.economist.com/news/briefing/21730870-economy-based-attention-easily-gamed-once-considered-boon-democracy-social-media <comment><USER2> When George W Bush won the election it was all the fault of Fox News and right wing radio.

Now that HRC lost the fault now lies allegedly with social media and evil foreigners.

It's like people blaming comic books, TV, rock music and video games for what they see as the failings of youth.

Acknowledging that the Democrats chose poor candidates in Gore and Clinton and that winning three Presidential terms in a row is hard is apparently harder than blaming people for voting the 'wrong' way on some new media development.

Clinton spent 1.2Bn and had loads of young people working on media. They probably weren't just telling truths about Trump. But apparently a few hackers around the place were vastly better than them.

<comment><USER3> I get that you don't seem to like Democrats - that's fine, I don't much care for them myself (although Republicans probably even less). However, the problem we are facing today is different than just spin. People are fundamentally trying to alter the public's perception of truth, not just spin or political opinion, and they have found that they can do this by saying a lie loud enough and often enough.

And in case you think this is just opinion/spin itself, check this out:

[https://www.texastribune.org/2017/11/01/russian-facebook- pag...](https://www.texastribune.org/2017/11/01/russian-facebook-page- organized-protest-texas-different-russian-page-l/)

There are foreign powers _cough_ RUSSIA _cough_ actively trying to disrupt/damage/destroy our democratic institutions. Considering the ongoing investigations by Mueller we still do not know if POTUS is a puppet, through threat of blackmail or evidence of dirty laundry, to Russian agents.

This a real thing. This is important.

<comment><USER4> The whole "let's blame it on Russia" thing is getting boring. At one point, my dear American friends, you'll just have to face the mirror.

<comment> aaron-lebo It's funny that we can't just meet at the obvious middle ground.

Russia didn't win the election for Trump, but you are kidding yourself if you believe it didn't play a factor. US democracy has _a lot_ of work to do, but Putin is an ex-KGB strongman who assassinates his opponents and annexes neighbors. It's pretty obvious how he operates.

<comment><USER5> We do have a "trash heap"[1] of blatant lies about the Russia hacking from the "Unelected Deep State" (CIA/NSA/FBI), which just adds to lies from them that have been stacking up for decades. I don't trust agencies with histories of trying to murder civil rights activists like MLK, lying to get us to go to war in Iraq, lying about domestic surveillance, etc.

Then we have the DNC very literally and provably rigging the primaries in favor of Clinton.

You know what? I hate Trump. But give me a break. This Russia trash is just all a distraction. Trump blatantly supports unconstitutional programs like domestic surveillance and gitmo--this should be enough to impeach him alone for supporting an undermining of the US constitution and American's rights.

The fact that they need to rely on this Russia story which requires a number of shifting standards and "just trust us's", rather than in-the-open undemocratic authoritarianism here in the US, is probably a testament to failures of the human mind's ability to think in terms of, and stand up for, liberty.

I have been to Germany and Japan and the people are unbeleivably friendly and wonderful. What on earth is wrong with people that they can be coaxed into the evil dreams of tyrants--conflicts, authoritarianism--and is it happening again? Are we so different or special that we really think tyranny cant happen to us when we are going through the same patterns of history?

Probably, if we could just adjust the human factor of 'susceptability to sell their liberties and fall in line behind authority figures for short-sighted self-interest,' we would live in a much better world.

1 - [https://theintercept.com/2017/09/28/yet-another-major- russia...](https://theintercept.com/2017/09/28/yet-another-major-russia-story- falls-apart-is-skepticism-permissible-yet/)

<comment><USER6> _Trump blatantly supports unconstitutional programs like domestic surveillance and gitmo--this should be enough to impeach him alone for supporting an undermining of the US constitution and American 's rights._

See, statements like this are a part of the problem. Obama did these things too and noone cared. Given that why should anyone believe anything anyone says? And into that vacuum, a new kind of influence emerges, one that is not about policies but just about "my team winning".

<comment><USER5> I was trying to also make that implicitly clear, but failed to do so. I think if you read my comments below you will see this idea.

</comment></comment></comment></comment></comment></comment></comment><comment><USER7> Every time I read these stores on HN, I can't help but point out this: [https://www.technologyreview.com/s/509026/how-obamas-team- us...](https://www.technologyreview.com/s/509026/how-obamas-team-used-big- data-to-rally-voters/)

Obama was lauded for using "Big Data" and "Data Science" to _rally voters_. It's not hard to guess where his team got the data from.

Now the same thing worked against, for better or worse, people are going out of the way to chastise _social media_.

Where was this concern when the same companies try and collect as much information as they can - user preferences, tastes, political bends - all in the name of "enhancing" experience. There were tons of articles written on praising the same companies on how clever they actually were.

Lastly, it is funny that economist etc are acting holier than thou when they themselves would be collecting some form of data from their readers to _enhance_ ad revenues etc.

IMHO, its not social media rather letting the collection of personal information get out of hand which is at fault.

</comment><comment><USER8> It seems like it's so easy to manufacture majority opinions that don't actually exist. And people tend to vote based on how they think their group will vote. Take somewhere like reddit or even here, and look at the disparity between political opinions on ordinary threads in random places, and the top comments/voting patterns on explicitly political ones.

So yeah, I'll sign on to "gaming social media kills the democracy." The question is, what are we going to do about it? As an individual you don't have to participate in social media, sure, but that counts about as much as your vote does.

<comment><USER9> If it's so easy to manufacture majority opinions, why didn't the candidate with the biggest budget win? ($1.4B)

Social media over-amplifies outrage and pushes the most reactive stories to the top of the feed. That's a big problem, with or without foreign government involvement. At the same time, news controlled through a handful of TV networks wasn't a good state of affairs either.

It will be interesting to see how the media evolves.

<comment><USER10> Correct, it is _not_ easy to manufacture majority opinion.

In fact, we are seeing:

1\. HRC spent more

2\. HRC had total support from media (every major newspaper)

3\. HRC even had social media employees manipulating their algos and data to her advantage

And now, after HRC lost, we are still using the same mechanism, and lenses, to form conclusions about why she lost.

That's the definition of insanity.

<comment><USER11> 2 is only the case if you limit media to things 45-50+ year olds consume (ie newspapers). And I don't even mean that there were blogs that disagreed with her: talk radio (I assume) and Fox didn't like her - and it is really not strange that newspapers supported the democratic candidate, especially in such a polarized election.

As for 1), she clearly spent too much on old-media. You don't win the presidential election by setting fire to 4 billion USD, even if you technically "spend" the most.

</comment></comment></comment></comment><comment><USER12> Anyone who wants to pin this on social media hasn't been paying attention to the history of the past 25 years. They've ignored the downfall of the newspaper business which used to take on the role of educating the American public. They've ignored the trend towards 24/7 TV "news" stations that focus more on inciting panic and fear than they do on educating the public. They've ignored the rollback of regulations that have allowed media conglomerates to homogenize what people are exposed to.

The reality is that if there were still journalists doing investigative journalism on par with Woodward and Bernstein and if Americans were getting their news from someone with the gravitas and ethical backbone of Edward R Murrow or Walter Cronkite, these "fake news" stories would be laughed at. But because our schools fail to teach critical thinking and our news either fails to inform people or cannot even interest people enough to watch, social media is the only way we have left for people to consume content and become educated. But since it's an open channel that anyone can participate in, is it any wonder that people would seek to co-opt it for their own purposes? It's little more than a modern day soap box and people have been bloviating their self-serving narratives that way for generations. What's changed isn't social media, it's the lack of adults with professional ethics supplying a baseline reality from which opinions must derive.

This is our generation's "yellow journalism" and it's a reminder of what happens when there's no one who takes on and is recognized for playing the role of establishing that baseline of accepted fact. Social media's reach is a symptom of the problem, not the cause.

<comment><USER13> > They've ignored the downfall of the newspaper business which used to take on > the role of educating the American public.

Which American news paper can you point out that's unbiased and isn't pushing some narrative. The truth is that printed press has been the megaphone of the ruling class since the beginning.

<comment><USER12> I can't name any today, but I think if you read my comment above, you'll find the names of two reporters that I believe lived up to that standard.

</comment></comment></comment><comment><USER14> Seems like the current narrative spread by all the mainstream media is "censorship is good for you because... Russia". Ironic, especially considering the commentary in the very same media outlets a couple years back when Russia was trying to censor the Internet.

</comment><comment><USER15> > When putting these media ecosystems to political purposes, various tools are > useful. Humour is one. It spreads well; it also differentiates the in-group > from the out-group; how you feel about the humour, especially if it is in > questionable taste, binds you to one or the other. The best tool, though, is > outrage. This is because it feeds on itself; the outrage of others with whom > one feels fellowship encourages one's own. This shared outrage reinforces > the fellow feeling; a lack of appropriate outrage marks you out as not > belonging. The reverse is also true. Going into the enemy camp and posting > or tweeting things that cause them outrage—trolling, in other words—is a > great way of getting attention.

This reminds me of this CGP Grey video: [https://www.youtube.com/watch?v=rE3j_RHkqJc](https://www.youtube.com/watch?v=rE3j_RHkqJc)

<comment><USER16> See also: The Toxoplasma of Rage - [http://slatestarcodex.com/2014/12/17/the- toxoplasma-of-rage/](http://slatestarcodex.com/2014/12/17/the-toxoplasma-of- rage/) \- which is a great discussion on the topic.

</comment></comment><comment><USER17> What is interesting is that this article paints the Euromaiden in a positive light. However, it was likely a very flagrant example of a US/NATO backed coup [https://www.google.com/amp/s/amp.theguardian.com/commentisfr...](https://www.google.com/amp/s/amp.theguardian.com/commentisfree/2014/apr/30/russia- ukraine-war-kiev-conflict)

When you use social media to influence elections in a neighbor of a geopolitical rival, don't be surprised when the same geopolitical rival learns how to use social media against you.

<comment><USER18> As much as I think the Russian interference in the US election was a catastrophe for American democracy, the blame lies at least as much with western intelligence services that continued to poke the Russian bear well after it started showing its teeth, with no real plan for what to do when it started biting.

<comment><USER19> 2011 Russian Election

Vladimir Putin accuses Hillary Clinton of encouraging Russian protests

[https://www.theguardian.com/world/2011/dec/08/vladimir- putin...](https://www.theguardian.com/world/2011/dec/08/vladimir-putin- hillary-clinton-russia)

</comment></comment></comment><comment><USER20> Didn't read the article, but i believe the threat to democracy is largely because Facebook is a centralized platform. They have an enormous amount of power because they can directly influence the type of information their users consume. They essentially have control of a 1b+ herd....

<comment><USER21> While that's true, I don't think it's the core of it.

As people, we like to be right. So we're drawn towards people who tell us we are right. Social media lets that take over our lives entirely - we can now live happily without ever hearing an opinion we disagree with. My neighbour and I might live one door from each other yet occupy totally different echo chambers.

I think you see this in the way people view Trump, Brexit and the like. No one's preconceptions are challenged any more.

<comment><USER22> I find that social media has the exact opposite problem. There's enough politically incindiary material on there that reading Facebook or Twitter frequently leaves me angry.

The friends and co-workers I spend time with in person have a much less diverse set of views than the broader group in my Twitter and Facebook feeds. Literally every person I spend real-world time with is wealthy, educated and liberal. Nobody ever says anything truly upsetting.

<comment><USER23> I actually don't get why facebook doesn't bury political posts in your feed. People are not going to be more "connected" when arguing about politics online.

From an AI point of view it's much simpler to detect if a post is political in nature

<comment><USER24> It seems like they are just optimizing for "engagement", and that outraged codes as egaged based on the metrics they collect.

</comment></comment></comment></comment></comment><comment><USER25> Social media is not the root cause. It's merely one of many tools to achieve the main goal which is society's root problem:

The root problem is this: America has slipped for a long time now. It has at its core been corrupted systemically by a destructive value system. Its culture is now based on the idea that to dominate those around oneself is the right thing to do (on a personal, social, national, international and worldwide level).

And those who feel the need to play this game _will_ dominate. They will reinforce and perpetuate this vicious circle - until society collapses. So you might want start counteracting now.

</comment><comment><USER26> Quote from the article (!): The population of America farts about 3m times a minute. It likes things on Facebook about 4m times a minute.

</comment><comment> nv-vn There's many things I see wrong with this argument/sentiment in general and I don't really know how to even address most of it.

Apart from what are mostly just biased judgements used to drive forward the narrative, there are 2 basic misconceptions that the article is trying to pedal as fact.

1: That democracy is supposed to inherently solve these issues; there's a clear reason why America was not founded as a democratic country. The founders of the US saw democracy in the same way they viewed autocracy. They called for a careful balance of different political systems in order to minimize the harm of each of these. Democracy was specifically avoided because pure democracy quickly devolves (and is synonymous) to "mobocracy." The article tries to place the blame for this on everything other than the system itself. However, the reason why these issues exist even in a system that is partially democratic (and obviously much more democratic than it was when the United States (or any other country mentioned) was founded) is because they have not taken over. Mob rule is slow to come to power, and this should be a warning to people that we're nearing the edge of the cliff (rather than that some have cheated the system into submission). It's also worth noting that democracy should never imply a system in which everyone independently forms views, as that is quite clearly impossible. Leading to the second point:

2: "Outside influences" are supposedly ruining political discourse. This idea just makes no sense to me. The blame placed on Russia for influencing the 2016 election is effectively for generating discussion. It is not for changing votes, because as far as we know that was never done. It's also not for lying to people; to argue that Russia was in the wrong for lying to people is 100% disingenuous because the authors of this article are just as happy lying to people in order to drive forth their own narrative. It seemingly blames the increased political division on right-wing politics by arguing how everything from Gamergate to Wikipedia has caused people to become more right-leaning. Ignoring the fact that they mischaracterize the entire movement of Gamergate (equating it to alt-right politics by linking it to 4chan, when in fact Gamergate was almost exclusively originating from 8chan, saying that it is trolling rather than a legitimate opinion to hold, etc.) and lie about Wikipedia's political agenda (it's quite easy to see that the major editors on Wikipedia are heavily left-leaning based on the frequent bans given to right- leaning editors), it's immediately clear from the graph showing party division that Democrats have "radicalized" far more than their Republican counterparts. In this scenario, they are using blatant lies and scare tactics to get across their opinion. How is this different at all from what they blame Russia/right- wing media/4chan for? Sure Russia might be using fake accounts to manipulate the public, but if the only solutions you can propose are limiting freedom of speech, you are doing much more to ruin democracy.

</comment><comment><USER27> Is this butthurt never going to end? Trump won, HRC lost. The reason? Maybe people do not want to elect a person under FBI investigation. Maybe people do not want to elect a person who does not know the meaning of "confidential". Maybe people felt like their voice was not being heard by politicians and media, and Trump would listen as an outsider.

Ah, who am I kidding. Let's blame Zuckerberg and the Russians!

<comment><USER28> > Maybe people do not want to elect a person under FBI investigation.

But Trump and his associates are also under investigation... And every single one of Trump's people are currently using private servers as well...

> Ah, who am I kidding. Let's blame Zuckerberg and the Russians!

Ah who am I kidding. You're already too far gone if this is how you think.

<comment><USER27> They are under investigation now. I'm talking about the reasons people voted for Trump. At that time HRC was the only candidate under federal investigation.

> You're already too far gone if this is how you think.

Please continue disregarding people who have a different viewpoint than yourself. It has worked very well for me.

</comment></comment></comment><comment><USER29> I think one of the most fundamental problems is the highlighting of things based on likes/dislikes/voting. It inherently drives people to polarization and is a very soft target for gaming. If you look at boards that use old chronologically ordered systems that are not threaded, there tends to be much more diversity of thought. A comment is just a comment - just like real life. People say smart things, people say stupid things. And the same people often do plenty of both. When you read a thread some comments you might love, some you might hate - but instead of focusing on one or the other you get a flow of ideas and views of all sorts. Instead in ordered/threaded systems we obsess over singular comments and the comments themselves become centers of discussion.

One of the first effects is that the only thing that gets visibility when there are 'opposed' groups _(in other words groups that do not upvote one another -- this effect is even more exagerrated when we introduce downvotes)_ is the largest plurality. One view has 51% of the support, the other has 49%. The 49%, even though it represents practically half of all views, would be buried anytime it's mentioned. You'd expect there to be about a 49% chance of any comment you read of being a 49% view. Instead you'll read each and every single 51% comment until you get down to the bottom sorted 49% views. Consequently we see groups begin to splinter off into their own little spaces where they can discuss things separate from the 51%. And just like that you have fermenting radicalism.

An analogy I quite like is to imagine we're trying to solve a math problem. The correct answer to this problem is 0. However, one side believes the answer is absolutely at least 50. And the other side believes the answer must be no more than -50. When these two groups remain within contact, they counter balance each other. But now let's isolate these groups. In the past when the -50 side chose to go -60 there would be some push back against that and it would help create a more of a central equilibrium. But in isolation without opposition, -60 sounds awesome. Why not -70, or even lower? And on the other side an equal but opposite push for 60, 70 and more is simultaneously happening.

The more segregated we are, the more out of touch with reality we become.

<comment><USER16> > _If you look at boards that use old chronologically ordered systems that are > not threaded, there tends to be much more diversity of thought. A comment is > just a comment - just like real life. People say smart things, people say > stupid things. And the same people often do plenty of both. When you read a > thread some comments you might love, some you might hate - but instead of > focusing on one or the other you get a flow of ideas and views of all sorts. > Instead in ordered /threaded systems we obsess over singular comments and > the comments themselves become centers of discussion._

My experience is like this: flat, chronological comment systems have more "diversity of thought", because they make it harder for people to actually engage with each other - so you get more shallow comments. Tree commenting encourages depth of discussion.

Interfaces are a problem, too. You can't have a meaningful discussion under a popular post on Facebook, because UX discourages it. You can't easily browse through hundreds of comments - you need to click a lot to show more comments, and each such click degrades performance of the site itself. On top of that, misclick somewhere, and your state is gone.

Upvotes are a solvable problem. In fact, both HN and Reddit solved it, by _not_ doing strict score sorting. Also, with proper UX, you can skim all comments quickly.

Ultimately, the problem with on-line discussion is the same as with lots of real-world issues - there is just too many people, and each one has an opinion.

<comment><USER29> View a discussion as solving a math problem. No, that's not entirely accurate but I do think the parallels are solid. Would you prefer threaded or chronologically linear? Why? The answer is almost unarguably the chronologically linear. Flat chronological systems don't really make it difficult for people to engage. People certainly can and do quote one another. And I think they also tend to progress the discussion much more rapidly than threaded systems for at least a couple of big reasons:

Threaded systems result in people repeating themselves constantly. For instance this topic currently has 16 top level threads and a total of 86 comments. However, I'd estimate 80% of the comments are saying the exact same thing in a variety of different ways:

\- 'Trump won because media manipulation.'

\- 'Hillary more actively manipulated the media and did not win, therefore the above is false.'

The 'personalization' of threaded systems leaves most participants oblivious to most of everything else that's being said -- even when said at roughly the same time. So instead of the direction moving forward it takes a sort of logarithmic divide with numerous divides repeating other divides. This is a very common theme in every topic.

Another major issue here is that as time elapses the number of people seeing any given comment rapidly approaches 0. Chronologically ordered systems enable lengthier discussion. Threaded systems all but ensure any discussion is dead after < 24 hours and often much sooner. So you have a sort of double whammy of not only a divide of progression, but less time spent 'progressing' as well.

And lastly, I think chronological systems also deter pointless nitpicks. For instance I really want to get snarky about thinking Reddit's voting system has solved anything, but what's the point? The only reason I'd discuss this is because of this personalization, but it's unlikely to end with either of us feeling any more well informed and it certainly has extremely little to do with the topic at hand.

<comment><USER16> > _View a discussion as solving a math problem. No, that 's not entirely > accurate but I do think the parallels are solid. Would you prefer threaded > or chronologically linear? Why? The answer is almost unarguably the > chronologically linear._

No, I would prefer threaded, of course. That's because it is natural way I, and I would imagine most people, think - by breaking down problems into parts, recursively, and solving them in isolation. Note that, whenever you write stuff like:

      1.
      1.1.
      1.2.
      2.
      2.1.
      2.1.a.
      2.1.b.
      2.2.
      3.
      3.1.

you're creating a threaded model, albeit with limitations of a static medium.

> _However, I 'd estimate 80% of the comments are saying the exact same thing > in a variety of different ways_

You'd be wrong :).

> _Another major issue here is that as time elapses the number of people > seeing any given comment rapidly approaches 0. Chronologically ordered > systems enable lengthier discussion. Threaded systems all but ensure any > discussion is dead after < 24 hours and often much sooner._

I disagree. My experience with boards using chronological ordering is even better at ensuring "the number of people seeing any given comment rapidly approaches 0". When you have 200 comments in a chronological system, most people aren't going to bother reading anything but the last few. In threaded systems like HN, it's much easier to handle, because you can skim the structure and zoom in on the subdiscussion that interests you.

As for discussion being dead after < 24 hours, that's most likely caused by HN stories being short-lived on the frontpage, and people being reluctant to engage once the story falls off it.

> _And lastly, I think chronological systems also deter pointless nitpicks._

What you call pointless nitpicks I call interesting tangents, which are often much more valuable that the original, primary topic, and they can grow on the side pretty much _thanks to_ threading.

> _The only reason I 'd discuss this is because of this personalization_

I don't understand what you mean by "personalization" and why you keep bringing it up. There is nothing personalized on HN itself, sans the top bard color (and showing dead posts).

<comment><USER29> Personalization is what happens in threaded systems. In threaded systems the number of viewers and participants in any given thread extremely rapidly approaches 2, then 1, then 0. Your analog of how problems are solved has nothing to do with the reality of how threaded systems work. In reality it would be:

      1. -> 1.1 -> 1.2 -> 1.1 -> Airplanes
      1.
      1. -> 1.1 -> 1 -> 1.1 -> 1
      1. -> 1.1
      7. Hotdog -> Apples -> Hotdogs -> Apples -> Hotdogs -> Apples -> Hotdogs
      1.
      1. -> 1.1
      Descartes -> Nietsche -> Russell
      1. -> 1.1

It's the key problem. When people isolate themselves from everybody else, there's no real progression in the discussion. On HN I can't even find new posts if I wanted to! When I last posted, 15 hours ago, I mentioned there were 86 posts made. That did not include mine. There are now a total of 89. So including yours that means one solitary other individual has since posted in this thread. I wished to locate his post to see where he fit in our little discussion, but alas that's not really practical in this model of discussion.

The reason posts die rapidly is because there is no notion of chronology. When you look at a post from 3 days ago you're mostly just going to find comments from 3 days ago. Now go to literally any reasonable size chronologically ordered forum and you'll find interesting topics that in many cases have been actively going for years, and it's phenomenally interesting to be able to clearly see and follow the changing views, discoveries, and so on over time.

Like you're inadvertently alluding to, I think this format is more popular in large part because it's a minimal effort, rapid response game. It's certainly fun and addicting, but I think it has a very negative effect on the overall level of content.

</comment></comment></comment></comment></comment><comment><USER3> One more comment to stir the pot....

Anyone here want to take a guess at which of these posts are paid propaganda? :P

<comment><USER30> That's not "stirring the pot", that's breaking the site guidelines, which ask HN users not to post insinuations of astroturfing or shillage without evidence.

[https://news.ycombinator.com/newsguidelines.html](https://news.ycombinator.com/newsguidelines.html)

</comment></comment><comment><USER31> Trump was not supposed to win the election. How do we fix that? Story #8000.

<comment><USER32> That is a very narrow and lazy reading of a pretty important issue--that the attention economy of social media is easily manipulated. It can go any direction and in any country...as mentioned in the article.

I have been pondering what the reaction by commentors leaving comments like yours would be to this kind of reporting if it had been Bernie or Hillary who had massive coordinated online efforts to influence the election in their favor executed by hostile foreign powers... It's an interesting thought experiment.

<comment><USER31> I was fully expecting Hillary to win actually and was just as surprised as everyone else when Trump won.</comment></comment></comment>