The Fourier Transform, explained in one sentence - <AUTHOR> http://blog.revolutionanalytics.com/2014/01/the-fourier-transform-explained-in-one-sentence.html <comment><USER2> Fourier Transform became trivial to me when I noticed that it's just a basis transform, as you would do with ANY other basis. Except this basis happens to be sine and cos waves of different frequencies.

i.e. you view the entire signal in the original domain as a single point in space of dimensionality equal to number of measurements, and then you project it onto the new (fourier) basis. For example, one of the new basis vectors could be sine signal of some frequency k. You find the component of the original signal along this new basis just as you would do for any other basis vector, with a dot product. The only slight complication is that to get the phase information you have to actually dot with a cosine at that frequency as well. The confusing e^ix complex number multiply "hides" the fact that we are actually doing two simultaneous dot products (since e^ix = sinx + icosx): one with the sine and the other with the cos, to get both the frequency and phase.

this is the intuition for DFT but for FT you just have infinite-dimensional vector space, done. This is much more intuitive to me than "spinning a signal in circle", which I personally find very to be a very confusing statement.

EDIT: granted, basic linear algebra concepts (vectors, basis transform) needed.

<comment><USER3> The isolated phrase "spinning a signal in a circle" is confusing, but the accompanying visualization of tracking a point on a spinning speaker cone is something that can be visualized.

More generally, your explanation may make sense to you, but it makes no sense to a layperson (i.e. me). But the linked short description, along with the speaker cone visualization, does make a reasonable amount of sense.

I've also seen a similar description in the past with accompanying animated GIFs illustrating the point, instead of the prose about a spinning speaker cone. I thought the animated GIFs made it even easier to understand. Sadly, I don't remember where I saw that.

<comment><AUTHOR> Is it this [https://upload.wikimedia.org/wikipedia/commons/1/1a/Fourier_...](https://upload.wikimedia.org/wikipedia/commons/1/1a/Fourier_series_square_wave_circles_animation.gif)

<comment><USER3> I've seen that before, and it's neat, but I don't think that's what I'm remembering.

</comment></comment></comment></comment><comment><AUTHOR> [http://betterexplained.com/articles/an-interactive-guide- to-...](http://betterexplained.com/articles/an-interactive-guide-to-the- fourier-transform/)

The animations are here

</comment><comment><USER4> I like to think of it like a vertical line of individual LEDs that sequentially shine to show current amplitude. (Like a Cylon visor or KITT the car.)

Sweep it sideways across a dark area, and you will see the waveform as an afterimage.

But start to _spin_ it around the center, and you get a blob of light, one that becomes tighter and more symmetric whenever the spin-rate approaches the rate of a repeating subpattern.

<comment><USER5> THIS makes the most sense to me of any of the explanations on this page.

</comment></comment><comment><USER6> i.e. color coding is necessary because math notation is typically expressed with ambiguous assumptions in service to absolute terseness.

As far as I can tell the only time it's attempted to combat this is in proofs.

Note that in a real paper or textbook, such a detailed description explaining each term would most definitely be absent, even without the color coding.

<comment><USER7> _Note that in a real paper or textbook, such a detailed description explaining each term would most definitely be absent, even without the color coding._

I disagree. In a textbook, it is very unlikely (and would be a sign of a badly written book) that there are terms in a displayed equation that are genuinely undefined. The worst case scenario is that they are not defined immediately next to the equation and presume that you have read the preceding material.

<comment><USER8> > The worst case scenario is that they are not defined immediately next to the > equation and presume that you have read the preceding material.

The textbooks I have used written by Russian mathematicians are almost entirely equation after equation of "explanation", derived from previous equations with the exact transformations in between left as an exercise for the reader.

There's a very distinct cultural difference for sure, but that doesn't make these textbooks less _real_.

Edit, to clarify: A lot of terms are not explained in natural language either as their very definition is an equation of other terms (feel free to apply recursively).

</comment></comment></comment><comment><USER9> One thing I don't fathom is why FT is always explained in terms of circles? For me it was always confusing this way; the concept was much more graspable when visualized in the terms superposition of sinusoidal waves.

<comment><USER10> Because those sinusoidal waves are merely projections (in the real and complex plane) of the true elemental component of the FT, the complex exponential, which is really a helix: [http://m.eet.com/media/1068017/lyons_pt2_3.gif](http://m.eet.com/media/1068017/lyons_pt2_3.gif)

A while ago I made some drafts for a series of diagrams to help visualize this ([http://imgur.com/vEcnVdn](http://imgur.com/vEcnVdn)) but unfortunately never got around to finish it ([https://en.wikipedia.org/wiki/Wikipedia:Graphics_Lab/Illustr...](https://en.wikipedia.org/wiki/Wikipedia:Graphics_Lab/Illustration_workshop/Archive/Sep_2013#RfC_- _Visualization_of_exponential_function)).

Anyway, for those who find it easier to think of sinusoidal curves, the animation in the Wikipedia article ([https://commons.wikimedia.org/wiki/File:Fourier_transform_ti...](https://commons.wikimedia.org/wiki/File:Fourier_transform_time_and_frequency_domains_\(small\).gif)) is a very good visualization (also, BetterExplained's rant on sines being explained as circles may resonate: [http://betterexplained.com/articles/intuitive- understanding-...](http://betterexplained.com/articles/intuitive- understanding-of-sine-waves/))

</comment></comment><comment><USER11> Think of FFT like music notation - a separation into notes, dynamics, and tempo.

Alexander Graham Bell came up with the idea of increasing the capacity of telegraph lines by combining several 'dit-da-dit' streams at different pitches. He called it a 'harmonic telegraph'. The idea was that a mechanical arrangement of reeds tuned to different pitches would pluck out each stream of data. This insight eventually led to the invention of the telephone.

Finally, if 'orthogonal basis set' is difficult to understand, think of giving someone 'left/right' driving directions. An FFT would then (roughly) be the mathematical equivalent of 'driving directions' for a clip of music or speech.

</comment><comment><AUTHOR> Here is another visualized Fourier [http://blog.matthen.com/post/42112703604/the-smooth- motion-o...](http://blog.matthen.com/post/42112703604/the-smooth-motion-of- rotating-circles-can-be-used)

</comment><comment><USER12> This is an extremely confusing sentence. My sentence would be:

> Every "nice" function can be uniquely decomposed into complex exponentials, > which in some contexts represent physical frequencies.

<comment><USER13> It's confusing because it explains "how." Your sentence explains "what," which misses the original point.

<comment><USER12> If you understand the "what" deeply, then the "how" is trivial. The decomposition is in the sense of an orthogonal basis, and so to compute the transform you just do a dot product in the relevant vector space.

</comment></comment></comment><comment><USER14> Neat idea but this is a discrete Fourier transform (the original is continuous, with an integral), and it's only "explained" in the context of signal processing. And even then, the explanation is imperative.

I agree with another commenter that the more useful explanation is in terms of a change of basis.

<comment><USER15> And it also relies on the rather fuzzily defined concept of "a bunch of points." Which bunch? Some particular bunch, or will any old bunch do?

<comment><USER16> yeah, I don't like the idea of 'spin your signal around a circle', and prefer 'compare your signal to a perfect wave' (multiplication).

</comment></comment></comment><comment><USER17> The Fourier transform is the map between sound waves and music as written on a staff.

That's an informal statement with some hand-waving since, for example, music notation is discrete and sound waves aren't, but that's the main idea.

<comment><USER11> Saw this after posting my comment. I agree this is the simplest way to think of an FFT.

</comment></comment><comment><USER18> I remember fondly a college lab experiment where we had to design a circuit that modulated a signal on a carrier (basic FM modulator).

The prep for the lab included a paper running all the math predicting the outcome, that included fourier transforms.

The moment we hooked the circuit's output to an spectral analyzer was the first time I saw years of theoretical math resulting on something "tangible": the carrier signal's peak and +/\- modulated peaks around it.

</comment><comment><USER19> I think all the efforts to make FT more intuitive are necessary because representation of signals in terms of complex numbers is a tricky abstraction. It's definitely worth taking the time to get comfortable with the idea of representing a signal in the complex plane without trying to understand the FT at the same time. Then all the spinning-around-a-pole verbiage makes a lot more sense.

<comment><USER20> I'm glad to hear that, as I didn't understand the pole analogy one bit.

</comment></comment><comment><AUTHOR> Understanding the fourier transform (from archive) [https://archive.today/ulPFk](https://archive.today/ulPFk)

(original link(dead) [http://www.altdev.co/2011/05/17/understanding-the- fourier-tr...](http://www.altdev.co/2011/05/17/understanding-the-fourier- transform/))

</comment><comment><USER21> >then there is frequency corresponding the pole's rotational frequency is represented in the sound.

Parse error.

<comment><USER22> I can't actually work out what this was meant to say. Anyone?

</comment></comment><comment><USER23> For a `slightly` longer explanation: [http://betterexplained.com/articles/an- interactive-guide-to-...](http://betterexplained.com/articles/an-interactive- guide-to-the-fourier-transform/)

</comment><comment><USER24> Here's how to make this with MathJax:

[http://adereth.github.io/blog/2013/11/29/colorful- equations/](http://adereth.github.io/blog/2013/11/29/colorful-equations/)

</comment><comment><USER25> Felt inspired after reading this this morning and spent my Saturday hacking up a little demo in d3:

[http://bbrennan.info/fourier-work.html](http://bbrennan.info/fourier- work.html)

</comment><comment><USER26> It just correlates a signal against harmonically related complex sinusoids.

<comment><USER27> Yeah, and don't forget to sum it all up and divide it by the number of samples.

</comment></comment><comment><USER28> Maybe an animation would serve to be a better vehicle for understanding.

<comment><USER29> [https://en.wikipedia.org/wiki/File:Fourier_transform_time_an...](https://en.wikipedia.org/wiki/File:Fourier_transform_time_and_frequency_domains.gif)

<comment><USER30> All of these explanations remind me of this: [http://www.joe- ks.com/archives_may2011/HowToDrawAnOwl.jpg](http://www.joe- ks.com/archives_may2011/HowToDrawAnOwl.jpg)

</comment></comment></comment><comment><USER31> Would thinking of the fourier transform as breaking a signal down into basic elements (like atoms) and figuring out how much of each atom is in the signal? Each different value of "K" then is like using a Ph strip to measure approximate energy b/c that particular strip reacts most strongly to a certain k.

</comment><comment><USER32> What about phase?

<comment><USER33> The complex number contains both cos and sin components. Sine is the y axis, cos is the x. From that you know the angle, i.e. phase, right?

</comment></comment><comment><USER34> isn't this theorem used to transmit signals across DSL connexions ? isn't it also used for wireless internet ?

</comment><comment><USER35> As I switch off the moment I see "signal" or "wave" let alone spinning it around the circle here is my take without any engineering intuitions:

-you can represent any (nice enough) function as sum of sines and cosines of given frequencies and amplitudes (frequency is how often the function hits the whole period, amplitude is by how much you multiple its value). The functions look this way: Amplitude* sine(x* freq)

-So you have your sines and cosines at various frequencies and you wonder what the amplitudes should be for every one o them so that if we add them all up we end up with the original function

-The idea to answer this question is to see how values of your sine or cosine correlate with values of original function. If it turns out that the original function is high in value when your sine/cosine is high in value then sine/cosine at this frequency needs to have higher weight than sine/cosine at other frequency where it doesn't correlate well with original function. Intuitively if you take functions which correlate well with original one with higher weight and those which doesn't with lower weight then you will have good approximation of the original function.

-Euler formula tells you what sine and cosine at given point are representing it as one complex number; to get value of sine/cosine at frequency different than 1 you need to multiple the argument by k*2PI (as frequency is given in beats/period and period is 2PI it's quite obvious why); So e^(xi) is value of cosx and sinx and e^(xik2PI) is value of those functions at frequencies different than 1.

So now let's see what this formula is:

-it's an average of things (1/N and a sum of N elements)

-those things are multplications of values of sine/cosine at given frequency at given point with value of original function at this point

-this average is going to be high if places where sine/cosine at given frequency is high and original function is high overlap (you multiple big number by big number) and low if described correlation is low; that's the concept of correlation

-the points are evenly spaced from 0 to n-1 (that's why n/N in the formula) and the sum goes over them.

That's it. No circles and spinning. The only trick is to realize that: e^(ix) represent value of sine and cosine at x and e^(ixk2PI) represents value of sine/cosine at frequency k (if k is 1, then it's standard sine/cosine as everything simplifies).

One sentence explanation could be: the more sine/cosine at given frequency correlates with original function the more that sine/cosine contribute to the original function.

</comment><comment><USER36> you know, it should be possible to generate some of these sentences from the mathematical notation directly to make concepts more understandable to the lay person (and people in general).</comment>


Running "sudo rm -rf /" [video] - <AUTHOR> http://www.youtube.com/watch?v=wWOjmvWPRvQ

<comment><USER2> All I know is that OSX users without a Linux background do __not __find "sudo rm -rf /" jokes funny...

</comment><comment><USER3> still no vote-down button...

</comment><comment><USER4> i did deltree wildcard on a school computer cause someone told me that's how you start oregon trails. wasn't a happy ending.

</comment><comment><USER5> See first comment to that video :))</comment>


Ask HN: Hacks to disconnect from news, social media? - <AUTHOR> I spend almost 3 to 4 hours on reading news, facebook posts, tweets, watching videos. I want to get rid of these. Right now,I have started asking myself a question before any task - how would it improve my life or support me finacially? If answer is positive, i do that task. But I think that is not the perfect way to handle this situation. So how do you handle internet distractions? How to get rid of these bad habits? <comment><USER2> I use TagTime [1] on the desktop to stochastically track where my time goes. When it inevitably and annoyingly pops up when I'm distracted from what I ought to be doing, that nudges me back on track.

[1] [http://tagti.me/](http://tagti.me/)

</comment><comment> wu-ikkyu Delete your facebook and Twitter accounts. At least remove the mobile apps.</comment>


The Future of Cooking Is No Cooking - <AUTHOR> https://www.linkedin.com/pulse/recipe-future-eating-yuen-daniel-cheng/ <comment><USER2> Another great article that focuses on cooking-as-a-service with some data on how cooking-as-a-service aka takeout/delivery is becoming more routine

[https://alexdanco.com/2019/05/09/cooking-as-a- service/](https://alexdanco.com/2019/05/09/cooking-as-a-service/)

<comment><AUTHOR> Thanks for sharing!</comment></comment>


Scientists Consider Adding Lithium to Tap Water - <AUTHOR> http://www.thedaily.com/page/2011/05/22/052211-news-lithium-1-5/

<comment><USER2> It's an interesting idea, would help more people than the one for pregnancy (not floride, the other one in tap water). But it's usable in nuclear reactors. Depends what it's put with, but I'd rather keep it for batteries (until we move onto batteries not using them).</comment>


Proof that Google is using its dominant position in the market to block others - <AUTHOR> https://twitter.com/hackfish44/status/589909683235872769 <comment><USER2> It's not permissible for any company. Really stupid that Google is engaged in this.

<comment><AUTHOR> Really crazy, they even have different error messages for dropbox and mega.</comment></comment>


Features Google Me Needs to Beat Facebook - <AUTHOR> http://nextparadigms.com/2010/08/04/3-must-have-features-for-google-me-to-beat-facebook/ Facebook is almost impossible to beat at this point, but Google still has a shot if they create the Google Me social network with these 3 must-have features. <comment><USER2> "Make an overall better product" I'm sorry but .. seriously, no shit?

<comment><USER3> The site is called Next Paradigms, what did you expect? :)</comment></comment>


Romance versus Realism: The Origins of the Novel - <AUTHOR> https://www.the-tls.co.uk/articles/romance-versus-realism/ <comment><USER2> The first novel that I'm aware of is Apuleius' _" The Golden Ass"_[1], which was written in the 2nd Century AD.

It's highly entertaining, and sounded very modern to my ear.

When I read of the novel form being invented more than a thousand years later I'm at a loss as to whether the people who claim that are simply ignorant of Apuleius' work or if I'm missing something.

[1] - [https://en.wikipedia.org/wiki/Golden_Ass](https://en.wikipedia.org/wiki/Golden_Ass)

<comment><USER3> You're missing something... sort of. Yes, these authors are aware of Apuleus. They might even be aware of day the Tale of Genji, or Dream of the Red Chamber, or Njall's Saga, or even say the book of Samuel in the Bible, all of which are earlier examples of novel like things! If you define the novel as a long prose story then obviously there are many examples before Don Quijote or Robinson Crusoe! The question that the article asks is the history of the modern western novel, in all its particularity.

<comment><USER4> One suspects that if these particulars were ever stated plainly (as didn't happen in TFA, for instance), many modern published "novels" would be found to lack them? It may be that the line was drawn here, and no further, merely because Elizabethan English is difficult for modern readers. Otherwise we'd realize that any written language has novels as a matter of course.</comment></comment></comment>


Ask HN: Problems to solve in a post-virus world? - <AUTHOR> What are new problems to solve in the aftermath of the Coronavirus? <comment><USER2> I'm with samizdis on this one. Covid is a black swan event. Solving problems unique to it (like toilet paper and ventilator shortages, mass work from home implementation, etd.) is probably an economic non-starter as a result. Instead we should be looking at solving the other problems that it exposed globally:

\- Fragility of single-country supply chains

\- Lack of a real social safety nets in many countries

\- Lack of focus on personal hygiene on a day-to-day basis

\- Non-sustainability of debt-based economic growth

\- Lack of childcare choices for many families, especially when both parents have to work to pay the bills

\- Disconnect between local wages and local cost of living in many cities for non-rich workers

Etc.

</comment><comment><USER3> Call me old-fashioned, but how about using the covid-19 crisis and its eventual aftermath to reflect on how we might solve the existing problems that plague us? Inequality, injustice, poverty and all the other usual suspects.

<comment><USER4> Too complex for our 7 inch diameter heads.

Enough data has accumulated in the last 20 years about our cognitive limitations. Which seem to compound as we construct groups and networks.

So "spreading freedom" fails, mass leaking info fails, "hope and change" fails, "self regulation" fails, bernie/corbyn et al bite the dust etc etc.

We need to reprove we can solve simpler problems, at smaller scales first. Those kind of people and groups are the ones I trust these days.</comment></comment>


The big problem with content marketing that no one is talking about - <AUTHOR> https://kolemcrae.com/im-getting-really-sick-of-content-marketing-e21581cd5b83 <comment><USER2> Yep, another thin article published on Tedium.

<comment><USER3> I thought it made good points. I don't really care that it's on Medium, not sure why that's an issue?

<comment><USER2> Tedium is overrun with thin articles by content marketers. The main tedium site also pops in a pop in window that wants to trick you into registering.</comment></comment></comment>


UI designers aren't doing UI design anymore - <AUTHOR> https://philip.design/blog/ui-designers-arent-doing-ui-design-anymore/ <comment><USER2> > But in this case a lot of the hard user interface decisions were being > pushed onto bootstrap. You use the jumbotron at the top. You have the nav > template. Here is a card. This is the table.

I wish articles like this explained what "doing UI design" means then. They clearly point out what the issue is, but they give us no tangible examples of a proper solution looks like. To all of us readers that don't know what proper UI design is, throw us a bone.

It appears design systems were produced (e.g., Bootstrap), engineers apply design systems with minimal oversight from design, consequently resulting in subpar products.</comment>


Show HN: Read-N-Search: Bring Kindle-style 1-click lookup to mobile browser - <AUTHOR> https://read-n-search.com/ <comment><AUTHOR> Hi HN! Ezo here. I love reading stuff. In my daily reading, one thing I find super annoying is the amount of clicks it takes to look something up on a mobile device. Inspired by Kindle's lookup feature, I built a browser that makes every word on every website lookup-able. All it takes is 1 click. Try it out!</comment>


How can a failed 40 year old tech entrepreneur find a job at a startup? - <AUTHOR> https://clarity.fm/questions/827/how-can-a-failed-40-year-old-tech-entrepreneur-find-a-job-at-a-startup?s=eml&utm_source=newsletter&utm_medium=email&utm_campaign=weekly_digest&utm_term=2013-12-27

<comment><USER2> This person does not say what type of skills he brings to the table.</comment>


If you enroll in Equifax's TrustedID you waive your rights to sue Equifax - <AUTHOR> https://twitter.com/wyatt_privilege/status/906120794593427456 <comment><USER2> So I checked their site and lo and behold I'm in the estimated 44% of Americans affected by this.

Here's my question, how can we, as a massive group, get some type of recourse?

I'm not talking about suing for money necessarily, I don't need it (though if I suffered some financial loss I'd at least like to be made whole).

I don't get it, the only reason identity theft is valuable is because companies like Equifax have inserted themselves into the process.

They've turned what should be public information into information that has so much ability to cause harm to our records (that we may never have asked Equifax to keep on us in the first place) that now we have to fight to protect all this data, when we're not even the ones attempting to put value to it.

So then Equifax offers identity monitoring services at a price. Then they leak most of their data. Then they offer their monitoring services to us, because now they're more needed than ever. So I'm gonna let the drug addled burglar watch the dog for me when I leave town?

You can't really not play the game, but even if you try not to they're still using you as a pawn.

Wouldn't it make sense to treat identity theft as a crime where the lending institution was stolen from? Why couldn't I sue Equifax et al. for libel when they have incorrect records on me that they won't remove in a timely fashion?

Luckily for my I've got a guy that manages my finances to a degree, and part of it is keeping tabs on anything showing up in my credit profile- but now I'm a juicy target because all I did was pay back any money I've ever borrowed in a timely fashion like I said I would?

<comment><USER3> 86% of all US credit card holders (of which there are only 167 million)

<comment><USER4> "only"

<comment><USER5> Out of 250 million adults that seems lower than I would of thought.

<comment><USER3> Many things add up here. 2/3 of millennials don't have a credit card. That's about 52 mil you take away there. Then you have about 3 million Muslims in the US, who depending on religious observance may not be using credit cards. Then you have all of the people whose income is low enough that credit cards aren't even a consideration.

</comment></comment></comment></comment></comment><comment><USER6> IANAL, but this contract would not seem to be valid because it does not include consideration[1] for the users entering it. Why would you give up your right to sue for a data breach by enrolling for a service to protect yourself from it? That seems like a protection racket.

[1] [http://www.nolo.com/legal-encyclopedia/consideration- every-c...](http://www.nolo.com/legal-encyclopedia/consideration-every- contract-needs-33361.html)

<comment><USER7> Yeah, sorry, IANAL either but that's total BS. The user has consideration in the form of being able to use the service.

For those who are unaware, contract law deals with a process of people exchanging things, usually in the form of promises -- "I will mow your lawn in exchange for $30" is a contract, even if it is never written down. There are a lot of interesting ways that this law works: for example you will see reasonably often something like "I'll give you $30 to mow my lawn" / "Deal!" / "What about $20?", where the one side seems to be assuming that there is no actual contract until they both say "Deal!" \-- but actually the law believes that the first person implicitly consented simply by the form of the language of the "offer" above and if the sums were larger this could hypothetically be the sort of thing that a lawsuit begins over.

The "consideration" idea is about this word "exchange" that I started off the last paragraph with, it says that contract law explicitly does _not_ apply with things that are just given away for free. If you say "Hey after I mow my lawn tomorrow I'll mow yours", and your neighbor says "great!", and then something comes up tomorrow so that you have to cut the job short only mowing your lawn and not your neighbor's lawn, the law says _that was not a contract_ and your neighbor cannot sue you to mow their lawn for free. How do we know it wasn't a proper contract where things were exchanged? Because _we can see that you don 't get anything out of it_. But "get anything out of it" might get into very abstract territory: for example if you are known among your neighborhood for collecting the dead grass you've mowed and turning it into expensive compost, and that's the reasonable expectation, that could be consideration. At some point -- possibly presently, I haven't reviewed them for this post -- the Creative Commons licenses said something like "to the extent that this is a contract, the consideration for me is that I'm getting to see my work used by other people who I don't know."

This exception to contract law obviously does not apply to the terms-of- service agreements for paid services. It _might_ hold if you are not notified about the terms of service prior to making the agreement, but US law tends to be a bit lax about the details here and usually says "well if you used the service _anyway_ after you found out about the terms of service then you agreed to be bound by those terms." See the cases on "shrinkwrap licenses" for details.

Note also that most free-software copyright licenses and so forth are simply not contracts; that doesn't mean that they have no legal standing, but just that their legal standing isn't in _contract law_ per se.

<comment><AUTHOR> What can invalidate a contact though is conscionability.

If the consideration is unconscionable, a court could invalidate it. The classic example is selling a million dollar life preserver to a drowning man. Such a contract would be unconscionable.

In this case, Equifax has thrown us into the water, and is willing to give us the life preserver for free if we're willing to forget that they did it in the first place.

</comment></comment></comment><comment><USER8> I haven't enrolled, but wouldn't you be able to argue that because their information was leaked you weren't the one who signed up?

<comment><USER9> This is not only a valid point, but a scary one :/ You can't prove who it was, if you could, then we wouldn't have this mess in the first place.

</comment></comment><comment><USER10> You waive your rights to sue TrustedID, not Equifax.

Edit: And yes, it's a subsidiary, but you absolutely retain the right to sue the parent company for an event that occurred before you agreed to these ToSes requiring arbitration for disputes with the subsidiary. You just now can't sue TrustedID if they fuck up their credit monitoring.

EDIT 2: Here are the _actual terms_ , not a selective screengrab of a scary- looking bit from Twitter: [https://trustedidpremier.com/static/terms](https://trustedidpremier.com/static/terms)

</comment><comment><USER11> Current headline:

> If you enroll in Equifax's TrustedID you waive your rights to sue Equifax

Is something like that even legally possible in the US? I know in my country it isn't.

A) You can't waive certain rights, even if you say so in a contract.

B) A contract that is general purpose, and not individually compromised by both parties, has even stronger protection. If you can convincably argue that you would not have assumed a clause, it is not valid.

C) Rules defined by laws overwrite contracts. So a law saying you can sue overwrites a term in a contract saying you can't.

Triple protected. Even if the US is more "free" in that regard, some of that protection must exist as well, right?

<comment><USER12> Your can't waive your right to seek remedy in the event of a breach of contract, but US courts have ruled that clauses requiring mandatory arbitration from a private arbitrator instead of going through the public court system are legal.

Theoretically, it's just as fair to be heard by a neutral third party, but the biggest difference is that if you agree to arbitration, there's no equivalent of a class-action complaint meaning each impacted individual would have to file an arbitration claim separately.

<comment><USER13> In Brazil, mandatory arbitration is valid only on non consumer contracts.

</comment></comment></comment><comment><USER14> The title does not match the terms of service to which the tweet links. IOW, no, that's not what it says. But this about the sixth story that's cropped up on HN about waiving your rights, so getting the crowds to wipe the froth from their lips is probably a lost cause.

</comment><comment><USER15> IANAL, but the document refers to TrustedID, Inc., a subsidiary of Equifax, not Equifax itself. I've seen arbitration clauses in many terms of use before, so I don't get the impression that this is nefarious. Again, IANAL.

</comment><comment><USER16> looks like Equifax responded to this point specifically in the terms of their 'see if you got screwed[0]' site:

"2). NO WAIVER OF RIGHTS FOR THIS CYBER SECURITY INCIDENT In response to consumer inquiries, we have made it clear that the arbitration clause and class action waiver included in the Equifax and TrustedID Premier terms of use does not apply to this cybersecurity incident."

[0] [https://www.equifaxsecurity2017.com/](https://www.equifaxsecurity2017.com/)</comment>


Creating PDF Reports with Pandas, Jinja and WeasyPrint - <AUTHOR> http://pbpython.com/pdf-reports.html

<comment><AUTHOR> I also found the two previous articles quite interesting: [http://pbpython.com/pandas-pivot-table- explained.html](http://pbpython.com/pandas-pivot-table-explained.html) [http://pbpython.com/pandas-pivot-report.html](http://pbpython.com/pandas- pivot-report.html)</comment>


Ask HN: Video conferencing solutions for startups? - <AUTHOR>

I am looking for a video conference solution that is stable, preferably low budget, for a 3-4 party video conference. If it records and saves the video-conference that would be a great feature, but not a must have. Would appreciate your insights and advice. <comment><USER2> you might want to take a look at oovoo.com, don't know if it's capable of video recording though...

<comment><AUTHOR> This seems like a great solution! Thanks!

</comment></comment><comment><USER3> ichat :)</comment>


The Notre Dame fire and the future of history - <AUTHOR> https://www.wired.com/story/the-notre-dame-fire-and-the-future-of-history/ <comment><USER3> > A new wall doesn't contain [traces of its original craftmanship], even if it > looks exactly like what once stood. "Do we clean it up and make it all look > unified, or do we try to let the memory remain?"

I am very unhappy that Notre Dame burnt. Having said that, I don't see it as "oh no, history has been destroyed" but rather as "this _is_ the history of the Cathedral". If it's still standing (and it seems like it will be), people will talk about this fire for hundreds of years, the same way we talk today about how it survived the French revolution.

Douglas Adams has a great quote on how a building its more than its materials, which you can read in [1]. If we use 3D scans and modern technology to reconstruct the Cathedral to the way it was, I wouldn't see it as "Disneyland" (as the article puts it) but rather as an example of how far we have come and what we can do when we put our minds to it, and how the story of our civilization is written not by design, but rather by accident.

[1] [https://www.goodreads.com/quotes/742883-i-remembered-once- in...](https://www.goodreads.com/quotes/742883-i-remembered-once-in-japan- having-been-to-see-the)

<comment><USER4> Great take. Also good to remember that a Temple of Jupiter once stood where Notre Dame is. After that was destroyed, a basillica stood there, and then a Romanesque cathedral. That last one, which was nearly 700 years old, was torn down to build the Gothic style Notre Dame.

The people who built Notre Dame tore down what to them would have been ancient history. Those other buildings were hundreds of years old by the time Notre Dame was built. 800 years ago, Notre Dame was the change that destroyed a 700 year old historical building. And the new construction was built in a super- modern style. They didn't try to make it look like the old building they tore down, they built it with the most modern techniques in a super trendy style.

Much like death and rebirth are cornerstones of the Christian religion that Notre Dame represents, death and rebirth are fundamental to Notre Dame itself.

<comment><USER5> While I totally agree with your sentiment, I'm not sure how I'd feel about tearing the whole thing down and building something brand new in its place. Interesting to ponder why that is.

<comment><USER6> In Rome I can think of one church (San Clemente Basilica) that was built on top of a pagan temple, which then had another church built on top of it, which then had the current church built on top of it. You can in fact tour all levels of it. Much of ancient Rome lies at a lower level than the current city, so those buildings are now basements or buried. In many cases that is what happened, not wholesale knocking down of the old buildings.

<comment><USER7> Here's a great blog post about San Clemente [https://www.exurbe.com/the-shape- of-rome/](https://www.exurbe.com/the-shape-of-rome/) (in which Freud battles his vertigo...)

<comment><USER8> This is a great post about a whole deal more than just San Clemente.

It could almost be called a "brief" history of Rome.

But then, maybe San Clementes history IS the history of Rome.

</comment></comment></comment></comment></comment></comment><comment><USER9> The thing that amazes me about Notre Dame, and several other structures of that era, is that it took 200 years to build. The reason this is so amazing is that the architects and planners knew it would not be completed in their lifetime, and yet they progressed for a greater cause.

We don't really have projects like that anymore. Contemporary structures and infrastructure are designed to be completed within the lifetime of the creator.

We might be able to attribute that to advances in technology allowing for faster development times. But sometimes it seems we've lost sight of the grandeur that existed at those times, and perhaps we are not challenging ourselves enough.

<comment><USER10> Back in the days when Kings reigned for tens of years, whereas now we have 4 year politician cycles...

<comment><USER11> But remember the cathedral was built, owned and run by a supranational organization, sometimes supporting, sometimes in conflict with the monarch.

<comment><USER12> But was it _funded_ by that organization? I was under the impression that big projects like cathedrals were used by the church as essentially huge visible PR projects, which attracted funding from people who wanted to be _seen_ to donate (providing PR for themselves). Some of the funding might also have been siphoned off to the church itself, I can imagine.

This pattern continues today – witness the speed at which funding for rebuilding has been publicly pledged by people wishing to be widely seen to do so.

</comment></comment></comment></comment><comment><USER13> A Parisienne friend of mine said last night when we discussed the fact that I never went inside, while she had: "Actually it was a horrible experience. Loud Americans everywhere taking pictures with their flashes."

Cities like Venice, Barcelona, Paris and Amsterdam need to address how we can preserve history while also considering how unfettered access makes it unappealing to participate as a local.

[Edit: I don't mean to single out Americans! That was just her comment. I know it applies to all unruly tourists of all countries]

<comment><USER14> I work in the travel industry. I'm always amazed that people are still flocking to those traditional tourist destinations in such huge numbers. Sure, before the internet, travel research was much harder to do and going to places like Rome or Barcelona was a safe bet. But now, with Kayak and TripAdvisor making trip planning easier, Instagram and blogs making it easier to find destinations, cheap flights becoming more common.. it's just so easy to find cool destinations that are a little more off-the-beaten path, not to mention, they're much cheaper! And yet, Paris and Venice are still absolutely flooded with tourists year-after-year.

<comment><USER15> That's probably making the assumption that "a little more off the beaten path" is on most people's selection criteria. The evidence suggests it's not and the Internet (and cheap flights) just makes it so easy to pick the obvious "best" places. And, if anything, social media like Instagram probably increase the desire of people to visit the iconic places so that they can share them online.

TBH though, for a lot of places like Paris, going outside of peak times-- assuming you have the flexibility--go a long way towards decreasing the crowds factor, at least away from the "must see" sites.

</comment></comment></comment><comment><USER16> Buildings of this age are better thought as palimpsests, mutable structures repurposed over generations. The building survived wars, revolutions, renovations and neglect. The spire that toppled was itself a modern addition that after a century is now mourned as canonical.

The building will be restored and revised and will be beloved again. Some will complain it's not the same, some will swear it's as good as it was and some will celebrate "improvements." I just hope the acoustics survive, though IMHO there are other, smaller churches that sounds better.

There's plenty of hideous stuff in Paris as well but I won't name names because what I consider dreadful some celebrate -- and perhaps we're both right.

(former Paris resident, though I wouldn't call myself a "Parisian")

<comment><USER17> Let's hope they don't "improve" it with an Apple store inside.

<comment><USER16> That would be perfectly consistent with some earlier uses of the building. Despite the story of jesus booting the money changers from the temple, for centuries big cathedrals like nddp were large general-use public resources, typically one of the only major building for miles.

As it happens nddp was built with some other palaces already there (e.g. pieces of what became the louvre) or contemporaneously under construction (e.g. Sainte Chapelle). But still it almost certainly housed businesses among other activities over the centuries.

</comment></comment></comment><comment><USER18> Let's assume that the goal is to rebuild Notre Dame as authentically as possible, except for whatever changes are absolutely necessary for modern safety standards (fire control; toxicity of paints; etc.) And that includes using the same kinds/maturities of wood, same kinds of marble, same wood varnish, etc.

And let's assume that we're okay with modern building _methods_ (such as cranes) as long as the results are the same.

Do we still have access to all of the specialized knowledge that went into that building? E.g., stone masonry, wood carving, preparation of varnishes, etc.? And is there enough supply of the required building/decorating materials?

Does the world currently have enough qualified artisans to allow construction at some "acceptable" pace? Heck, do modern governments and Parisians even have the _patience_ for a multi-decade construction project to succeed?

<comment><USER19> I'm trying to find the tweet again, but I read that they've been "farming" the oak trees required to replace all of the wood in Notre Dame at Versailles for the last 150 years or so.

Paris seemingly has good contingency plans for events like this.

EDIT: [https://twitter.com/_theek_/status/1117895531563372544](https://twitter.com/_theek_/status/1117895531563372544)

<comment><USER20> I don't think this story checks out. I'm sure they have some eligible oaks at Versailles but the roof needs ~13,000 of them. Hence why they called the latticework 'the forest'.

The largest oak forest operator in France has offered to find the trees needed: [https://mobile.francetvinfo.fr/culture/patrimoine/incendie-d...](https://mobile.francetvinfo.fr/culture/patrimoine/incendie- de-notre-dame-de-paris/notre-dame-de-paris-un-exploitant-forestier-francais- offre-du-bois-pour-la- reconstruction_3400571.html#xtref=https://www.google.com/)

<comment><USER21> The Versailles oaks are for the Steeple only, not the whole roof (which needs the 13k).

</comment></comment></comment></comment><comment><AUTHOR> For the last half-decade or so, an architectural historian named Andrew Tallon worked with laser scanners to capture the entirety of the cathedral's interior and exterior in meticulous 3D point clouds.

<comment><USER22> Should the interior be recreated as it was, or simply rebuilt in a new way? Attempting to recreate it might result in never-ending comparisons to the original.

<comment><USER23> That is a good question that is very complex to answer. This isn't just a historical building, it is a building. There was one (two?) pipe organ inside that were used for beautiful music, modern design can improve the acoustics making the music better. This was a cathedral, I assume still in use for worship, could modern design help that purpose? This was a beautiful example of historical architecture, should we recreate that exactly to add study of architecture? This is a valuable building site in the middle of Paris, they could build a skyscraper to better use the land.

Those are just a few of the competing concerns. There is a good argument to be made for each (even the skyscraper), whatever you choose will be at the expense of the others. We are forced to have this argument now: expect a lot of shouting and nobody to be happy with the end result. Try to see all sides. (I was going to say help to a reasonable compromise, but then I realized that compromise is not always reasonable)

<comment><USER24> >There is a good argument to be made for each (even the skyscraper)

I'm curious...what's the good argument towards replacement with a skyscraper?

<comment><USER25> Prime spot right in the middle of Paris? (though, with maximum height regulations in Paris, a skycraper there wouldn't be very tall)

</comment></comment></comment></comment></comment><comment><USER26> I read several interviews today with the master builders of big cathedrals in Germany and Austria. Basically, they are all deeply shocked, the consensus being that nobody thought a catastrophe like that was possible in the 21st century. This appears to be the first major fire in a European cathedral after the second world war, where of course many cathedrals burnt down after bombings (for example, a similar fire broke out in St. Stephens in Vienna in 1945) [0]

In several regional papers, they are now discussing if such a fire would be possible in the local cathedrals (it would, of course) and whether sprinklers should be installed in wooden roof frameworks (which brings all sorts of problems). Only some newer cathedrals (for example the one in Cologne) or cathedrals that burnt during WWII have steel frameworks under their roof.

On an emotional level, I am quite touched by the international reaction to this catastrophe. Basically all cathedrals here in Germany rang their bells today at noon out of respect.

[0] [http://www.pwein.at/Webpage- Holocaust/Geschichte-1938/Stepha...](http://www.pwein.at/Webpage- Holocaust/Geschichte-1938/Stephansdom-3.jpg)

<comment><USER27> The cathedral in Leon, Spain, a slightly older gothic church, was the scene of a very similar fire when a badly grounded lightning set the wooden roof on fire in May, 1966.

The damage wasn't as pronounced thanks to the stone used for the top, which was chosen for its lightness but had the added benefit of having volcanic-like properties. And especially thanks to a local mason who made the call to pull the fire brigade and sacrificed more of the wooden roofing to prevent the water weight from making the vault collapse.

I haven't found much info in English but here's a detailed account in a Spanish blog: [http://cosinasdeleon.com/el-incendio-de-la-catedral-de- leon/](http://cosinasdeleon.com/el-incendio-de-la-catedral-de-leon/)

</comment></comment><comment><USER28> Microsoft had a pretty impressive demo of a 3D recreation of Notre Dame using photos scrapped from Flickr back in 2007:

[https://www.ted.com/talks/blaise_aguera_y_arcas_demos_photos...](https://www.ted.com/talks/blaise_aguera_y_arcas_demos_photosynth?language=en)

I believe they used to have a viewer for the model available on the web, but I can't seem to find it at the moment (maybe it died when Microsoft killed their PhotoSynth product).

</comment><comment><USER29> Notre Dame is more famous now than it has ever been. A new chapter has just been added to its history. A building is just a building, the Chinese have been building replicas of pretty much every famous European landmark. They, like buildings, are probably even more imposing than the originals. But they don't have the same history of destruction and rebirth that the originals represent.

<comment><USER30> Oh China has plenty history and destruction, just take one example [https://en.wikipedia.org/wiki/Old_Summer_Palace](https://en.wikipedia.org/wiki/Old_Summer_Palace)

It's a royal palace that was pillaged and burnt down, that would require unmeasurable amount of money to restore.

<comment><USER29> Of course, I don't doubt that. Just saying that a building is more than just a building. China has its own historical landmarks. They also have an exact copy of the Norte Dame: [https://www.asiatimes.com/2019/04/article/still-want-to- see-...](https://www.asiatimes.com/2019/04/article/still-want-to-see-notre- dame-go-to-china/)

</comment></comment></comment><comment><USER31> > Parisian fire brigades held the line. They kept the fire from spreading into > the towers of the western face of the cathedral.

It's hard to overstate how hard this fire would have been to fight. That any of the structure was saved is testament to the skill and herculean efforts of the firefighters involved. If they had simply kept the fire from spreading to the buildings north of the cathedral, that would have been a "win".

It's clear from reports that the decision was made very early on to salvage what they could from the structure and set up to defend the western towers. The first fire streams put in place were in defense of the towers, not attacking the main body of the fire[1]. That was clearly the right tactical call, and trying to fight the fire head on likely would have resulted in the loss of the whole structure.

To highlight a few of the challenges...

The building itself had a huge amount of fuel (the tons of wood that have had centuries to dry), plus the significant amount of wood in the construction scaffolding supporting the renovation.

The fire likely burned undetected for some time in the attic space. By the time it was visible, it had a solid head start, and extinguishing it was never an option.

Once the fire was detected, getting sufficient manpower and equipment to the scene would have been the next challenge. The cathedral is on a small island, with limited access, and limited room to park vehicles in the vicinity. This would have been an "all hands on deck" fire, with off-duty staff recalled, but that takes time, and the initial incident had to be managed with relatively limited manpower (relative to the scale of the fire).

The next issue would be getting enough water to the scene. A fire like this requires tens of thousands of gallons of water per minute. There's likely only one or two water mains serving the island, which puts a hard cap on the amount of water that could be drawn from the local hydrants. The fact that it's an island obviously means there's a huge amount of water near by, but using that water has its own logistical challenges, as it requires special equipment (you can't 'suck' water through a soft fire hose), and special training. While I'm sure they had some capability to "draft" water from the river, it's not a skill that gets used often by urban fire departments, and it's likely not something they were set up to do in any significant way. In any large scale incident like this, there are often more firefighters working in "water supply operations" than there are actually fighting the fire.

Huge kudos to the firefighters on scene, and hopefully they'll have an opportunity for some well deserved rest in the coming days.

[1] [https://twitter.com/shivmalik/status/1117864730453061634](https://twitter.com/shivmalik/status/1117864730453061634)

<comment><USER25> I'm pretty sure that you can park a certain number of trucks on the parvis in front of the cathedral.

<comment><USER31> Indeed. The problem is, that's on the wrong side of the structure from where the fire (originally) was. Running hose lines 500+ feet isn't really an option (the friction loss over that length means you don't have enough water pressure for an effective fire stream).

<comment><USER25> Yeah. Especially since I don't think there's a lot of access to the Seine side of the cathedral.

</comment></comment></comment></comment><comment><USER32> Hagia Sophia in Istanbul is one in peril from both politics/religion and physical condition. Visit soon if you have any interest in ever seeing it.

</comment><comment><USER33> I feel optimistic knowing how widely surveyed this structure has been over the centuries and the vast amount of data collected, coupled with the abundance of resources available today, it can be restored to a condition, which will do it justice. There have been pledges made by Apple and LVMH today of significant finances, which will speed up the process.

A cross-section of The Notre-Dame:

[https://www.thechildrensbookreview.com/wp- content/uploads/20...](https://www.thechildrensbookreview.com/wp- content/uploads/2014/06/3.-Notre-Dame-Cathedral-cross-section.jpg)

Illustrator: [http://www.stephenbiesty.co.uk/home.html](http://www.stephenbiesty.co.uk/home.html)

</comment><comment><USER34> In the face of uncertainty after this tragedy, I find some comfort in knowing this data was collected and can be used in efforts to rebuild and restore.

Some of the techniques and materials may be lost to history, but the detail is perfectly preserved so at least there is a path to follow.

</comment><comment><USER35> It's only the roof for God's sake. plus the minitower. Nobody sees that from the inside. From the inside it looks nothing happened at all. Lots of hysteria about a minor incident. Compare it to the Vienna Stephansdome fire in 1945, where to big wooden blocks fell through the roof and destroyed the whole inner room. Even down to the catacombs. Or the catastrophic fire in Venice, where the whole church was destroyed by renovation works and was not even reerected! Or the destruction in Palmyra or the Twin Towers. They are gone forever. The Notre Dame roof and center tower is no problem at all to reerect. It's only wood after all, all the important parts are still there.

</comment><comment><USER36> On the topic of "history", there is a Spaniard (Justo Gallego Martínez) that started the construction of a cathedral in 1961 by himself [1]. He gained notoriety with an Aquarius spot [2]. If you are interested, there are some videos that show the inside [3].

There is even a movement to stop the demolition (it has not building permits) because many people consider it a monument.

[1] [https://en.wikipedia.org/wiki/Justo_Gallego_Mart%C3%ADnez](https://en.wikipedia.org/wiki/Justo_Gallego_Mart%C3%ADnez)

[2] [https://www.youtube.com/watch?v=wk9jGBjiBZI](https://www.youtube.com/watch?v=wk9jGBjiBZI)

[3] [https://www.youtube.com/watch?v=AhC2N0eK168](https://www.youtube.com/watch?v=AhC2N0eK168)

</comment><comment><USER37> Restoration is itself an art as well as a scientific and engineering effort.

Paintings are treated to remove as much detritus and patina as possible without damaging the underlying pigments or lacquers that might have been part of the original artwork (some might argue this is itself destructive and might accidentally go too far.)

To make this process easier to future treatments, restores take great care to make their contribution visibly obvious to a careful (and close) observer rather than blend it with the original.

I think something along these lines will be the best solution for all; perhaps we can avoid reinstalling that pike which - however beautiful in its own - <USER2> more suited to an Alpine parish church.

<comment><USER38> On the subject of painting restoration, there is a channel on Youtube called Baumgartner Restoration that makes documentary-style videos about restoring old paitings. Here is one of the more recent videos, where the restorer describes what he is doing and why it works: [https://www.youtube.com/watch?v=h8quhZLHVg4](https://www.youtube.com/watch?v=h8quhZLHVg4)

</comment></comment><comment><USER39> I have kind of mixed feeling on that. On one side I kind of see the fascination of looking at a construction that is almost 1000 years old. On the other side wood is wood. If the roof structure is rebuilt identically (and we most likely have enough pictures and blue prints to do so), rationally, does it really matter than the wood is not the original wood (and half of the wood wasn't the original wood anyway, and the spire wasn't the original spire either)?

</comment><comment><USER40> My view is that tons of buildings in Munich that we view as "historic" are mere recreations of the originals that were destroyed in World War 2. Notre Dame will be rebuilt, and it will merely be a part of its long history that it survived the fire. People will always long for how something was before, but unfortunately, that's not life.

<comment><USER41> The beautiful old Breton town of Saint-Malo was also rebuilt "historically", but not "exactly" \- where they could not find original plans or reuse stones from buildings, they recreated them in a style that they felt was a best approximation of how it had looked before. (That was after the Wehrmacht made a holdout of the town in August 1944, and the Americans dealt with it by expediently bombing 80% of the town to rubble.)

[] [https://paysages.ille-et- vilaine.fr/IMG/jpg/5_3_stmaloarretc...](https://paysages.ille-et- vilaine.fr/IMG/jpg/5_3_stmaloarretche_cle811e1e.jpg)

</comment></comment><comment><USER42> The BBC today published some experts' thoughts on what rebuilding will require. In short, much depends on how much the heat and debris affected the still-standing, critical structure.

[https://www.bbc.co.uk/news/world- europe-47952055](https://www.bbc.co.uk/news/world-europe-47952055)

</comment><comment><USER25> I went to take a look. There were so many people, it's sad that the fire has made it even more of a tourist attraction. As for the cathedral, it doesn't seem to be a lot of exterior damage, but all the roof and the spire have disappeared.

Also there's been a fire at the Al-Aqsa Mosque in Jerusalem. It's a bad day for old places of worship.

<comment><USER43> > I went to take a look. There were so many people, it's sad that the fire has > made it even more of a tourist attraction.

I wonder if you see the hypocrisy here.

<comment><USER25> I'm not a tourist, so I wouldn't call that hypocrisy. Rather more irony.

</comment></comment></comment><comment><USER44> With all this discussion of revival of old styles in this thread it is worth noting that France saw the revival of chant itself in the 19th century, which is in many ways an echo of that enchantment with the past. The musicologist Katherine Bergeron has a great book about it

</comment><comment><USER32> fwiw here's a picture of the attic above the vaults:

[http://manuelcohen.photoshelter.com/image/I0000l4VZKzgXgcI](http://manuelcohen.photoshelter.com/image/I0000l4VZKzgXgcI)

<comment><USER45> According to the legend this is Basilique Notre Dame des Victoires [0], not the cathedral.

Still beautiful though !

[0] [https://en.wikipedia.org/wiki/Basilica_of_Notre-Dame-des- Vic...](https://en.wikipedia.org/wiki/Basilica_of_Notre-Dame-des- Victoires,_Paris)

</comment></comment><comment><USER46> It's wonderful that they were able to save the cathedral. The Tuileries Palace, an important fixture of the French Revolution, is sadly only a garden now after it was destroyed in a fire.

<comment><USER43> Pretty nice garden though.

</comment></comment><comment><USER47> rebuilding doesn't have to destroy its historical value -- Osaka Castle has fallen and has been rebuilt several times in its 600 year history, most recently it was destroyed by WWII bombing raids (well, it was a 1930's era reconstruction that was destroyed) and was reconstructed in the mid 1990's and is still a historical site.

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

</comment><comment><USER48> And Apple donates a lot of money for the reconstruction. How about they just start paying their taxes instead of turning everything into some marketing scheme.

</comment><comment><USER49> [https://gigarama.ru/notredame/](https://gigarama.ru/notredame/)

</comment><comment><USER50> Perhaps time to discover or rediscover the Sainte Chapelle, which is near Notre Dame and arguably more spectacular.

</comment><comment><USER51> I'm surprised that we still have precious buildings that don't have sprinkler systems in them as that fires have been so common throughout history. The national history museum in Brazil too just recently.

It seems like we should be able to make a system that can be installed in older buildings that isn't unsightly and damages them at this point.

<comment><USER52> > It seems like we should be able to make a system that can be installed in > older buildings that isn't unsightly and damages them at this point.

This shouldn't be downvoted. That would be more interesting and useful work than most of the Apps everyone's working on.</comment></comment>


Explain Yourself Leveraging Language Models for Commonsense Reasoning - <AUTHOR> https://arxiv.org/abs/1906.02361 <comment><USER2> The model is trained end-to-end to answer common-sense-reasoning questions _after_ generating explanations for its answers, using sample human explanations as part of the training data.

This results in improved performance on the question-answering task.

This is fascinating, although in hindsight, not entirely surprising: inducing a machine to learn to model human explanations helps the machine perform better in testing.

A natural question follows:

Can we find ways to induce much larger models to learn to generate human explanations about a growing number of subjects of increasing complexity?

</comment><comment><USER3> Reminds me of the concept of "Social Stories": [https://en.wikipedia.org/wiki/Social_Stories](https://en.wikipedia.org/wiki/Social_Stories)

> Social Stories are a concept devised by Carol Gray in 1991 to improve the > social skills of people with autism spectrum disorders (ASD). The objective > is to share information, which is often through a description of the events > occurring around the subject and also why.

I'm wondering if this kind of "common sense" interactions could be leveraged to train models?

Here's a concrete example, "Being Angry and Safe": [https://youtu.be/R8c_Br8I_Tc?t=28](https://youtu.be/R8c_Br8I_Tc?t=28)</comment>


Ask HN: gmail not showing new emails on inbox? - <AUTHOR>

since a while it's not showing new emails on my desktop's inbox.. I need to go to "all emails" to see them, but on my phone emails just instantly appear. I have already sent a "send feedback", but it's still broken.
I also noted google delivering things first on my android's phone, like chats for instance: is google trying to move people out of desktop? are they just not paying a dime to fix those things?
anybody seen this same issue? <comment><USER2> Sorry to be blunt, but HN isn't your personal tech support service. If everyone on this site posted an "ask HN" whenever something didn't work, it would be inundated.

I suggest you contact Google support.

</comment><comment><USER3> Are you using a software client on your desktop or GMail in your browser?</comment>


New 3D printer uses standard A4 paper to make complex models - <AUTHOR> http://www.mcortechnologies.com/

<comment><USER2> The marketers working at the company should be taken out back and flogged. Show me the device and tell me how it works!

From what I can tell, it's like taking a big stack of paper, gluing all the pages together and then carving it into the object of your desires. (The carving and stacking order may be reversed.) And apparently, it's cheap, since it's run-o-the-mill paper.

<comment><USER3> Why don't they just use solidified wood pulp, and remove the paper gluing step? Seems inefficient to me.

<comment><USER4> Right, but you can't pop down to the local store and buy wood pulp (can you?). This does have the advantage of using something you can buy practically anywhere.

<comment><USER3> Hmm, in that case, the machine should generate solidified wood pulp from any paper waste. Then your source of material is much larger and cheaper - i.e. cast off cardboard boxes from the local supermarket, irregular shapes and sizes don't need to be glued together.

</comment></comment></comment></comment><comment><USER5> This is particularly interesting, especially as opposed to the plastic and resin-based printers. While less useful should someone want to actually use the printed parts, it definitely has its uses under a great number of circumstances, such as models (e.g.: dental, as they show), or cheap custom- fit packaging.

Looking at the cost of these models ($9 for the model of a head, $1 for the model of the teeth), I would love to have one of these just to print up things for prototyping ideas or just as models to paint. As well, I could see many companies adopting this as a secondary tool to the resin-based machines, being a cheaper way to prototype things roughly so they can refine it and then print a more complete prototype on the resin-machine.

On that note, anyone have any idea how much this machine will cost?

<comment><AUTHOR> endtwist, totally agree. the reduction of cost to that level would make this ideal for consumer applications too, like toys. Could imagine all sorts of uses for a tool like this, if it can truly produce parts that cheaply. I think the only other concern would be time. if it takes 10 hours to produce a model that is going to be a barrier.

<comment><USER6> 10 hours isn't a long time, relative to the amount of effort it would take to produce something similar with other materials or older processes.

<comment><AUTHOR> You are right, I'm just thinking about it in terms of production rather than prototyping. 10 hours is nothing in an engineering office, but if you are trying to produce low price point consumer products, or custom packaging, or something along those lines it becomes cost prohibitive.

<comment><USER7> Please don't use something this wasteful (paper) for production.

<comment><AUTHOR> Lallysingh, I totally agree with what you are saying, but you need to balance the "wastefulness" with the environmental benefits:

Lower embodied energy - With personal fabrication machines more products can be produced locally. This reduces the need for transportation, warehousing, returns, and a great deal of scrap.

Solid Waste Management - There is a raging debate in environmental circles regarding the use of paper vs. plastic grocery bags. It turns out paper bags have a number of problems. Their recyclability and biodegradability work in their favor though. These things could be composted or recycled. Plastic items for similar purposes will be in landfills for more than 10,000 years.

<comment><USER7> All very good points. Is there a way to do this without the rest of those sheets of paper going to garbage? Maybe if it glues small rectangles together across instead of a large sheet of paper?

Some of this reminds me of some of Stephenson's earlier work with raw material feeds being distributed as we do water, with local fabrication at home in a microwave-sized device.

</comment></comment></comment></comment></comment></comment></comment><comment><USER8> Paper based prototyping, like LOM (laminated object manufacturing), can produce parts with a similar texture to wood. They're pretty durable once finished, but a major problem is that when you're done you're part is stuck somewhere in a block of wood (a 8.5x11xN block in this case). The machine will hatch the negative areas for easier removal, but there is still quite a bit of post processing, and the final product is generally lacquered to prevent splitting.

I'm sure replicatorblog knows the current state of the art better then me, but, while this technology is cheaper than what was going on 5 to 10 years ago, its no more advanced. All of these cheap "3D Printers" have the same drawbacks people have been dealing with for a decade, they just cost thousands instead of hundreds of thousands, and are less accurate.

I feel like rapid prototyping/3d printing is going to be one of those things that is always x-years away from breaking into mainstream, where x is some constant.

<comment><AUTHOR> Jonhohle, I know what you mean, 3D printing always seems to be in the 5+ years portion of most technical reports by companies like Gartner. I'm not a big believer in the immediate application of 3D printing, but I think progress is being made. Companies like www.figureprints.com are starting to bridge the gap between science fiction and everyday commerce. While it is certainly "nichey" we should remember that we had rotisserie baseball on Prodigy before Google and Wikipedia.

You are also right that the low cost printers aren't much better. Their value is more in exposing smart people with diverse skill sets to the technology and from there bright entrepreneurs will find a way to commercialize it. We need hackers and marketers to understand the potential before we have Amazon.com

I wouldn't be surprised if the first big inroads are in toys and game related things, but quickly swing to critical areas like medical. In any case a fun area worth watching.

</comment></comment><comment><USER9> I had no idea that anyone still made whole sites in flash. Horriffic !

<comment><AUTHOR> yeah, neat technology, but the site is terrible. You can make realistic looking teeth out of copy paper and you bury the image in a crappy flash gallery 10 pics in? Hopefully the technology is better than the marketing.

<comment><USER10> Sometimes I wonder if the average person makes these amazing leaps of judgment (i.e. flash website = poor product) when they visit a site in flash.

Aren't you in the business of 3D printing also?

<comment><AUTHOR> Kirse, I didn't say the product was inferior because it had a flash website. I'm actually a big flash fan. My comment was more to do with their presentation of info. The 3D models they produce are amazing and should be prominently featured, not at the bottom of the list. I'm not in 3D printing actually, just blog about it.

</comment></comment></comment></comment><comment><USER11> Goodbye trees :(

<comment><USER12> Ah, but what if someone uses this device to prototype a system that reduces the amount of trees used for other purposes?</comment></comment>


Anki Shutting Down - <AUTHOR> https://www.vox.com/2019/4/29/18522966/anki-robot-cozmo-staff-layoffs-robotics-toys-boris-sofman <comment><USER2> Wow. This hits home for me.

In 2017, I was reselling Anki Cozmos to help fund a side project I was working on.

The buyers were consistently some of the most enthusiastic parents I had ever met. I had never heard a single piece of negativity towards Cozmo.

My favorite memory was taking the train for 2 hours each way to visit someone's home and help them troubleshoot their Cozmo's problems.

People here are claiming that Cozmo was too expensive, but I'd argue that Cozmo wasn't expensive enough.

Interested parents will pay a lot for high quality and well designed educational toys for their children. I know this because I was reselling Cozmos for 50%+ more than their price tag.

I had no idea of Anki's true ambitions in robotics and AI. I think it's that lack of focus that killed them.

There is absolutely a market for well designed educational toys, but it's not a business that needs 9 figures in funding.

I hope someone else will come in and take the lead, because this is a great niche, but one that doesn't necessarily need VC funding, just organic growth due to steady, incremental, product improvements.

</comment><comment><USER3> > 200 million in funding > 100 million in sales

Well, there's your problem right there. I have a feeling this was a company that would have done well if it had avoided the lure of VC funding, built its product and scaled slowly solving the interesting and challenging problems of building a home/play robot and getting consumers to like and want it, eventually selling to an Amazon or Google for a $100M+ exit.

Instead, they tried to fund their way to become a robot unicorn and died an undercorn.

<comment><USER4> Yeah, it's a shame tech entrepreneurs are so greedy. In most other fields $100 million in sales would (potentially) be a great business.

Same sentiment with respect to getting acquired. Having 4 or 5 giant companies control everything is terrible for the long term health of the industry.

</comment></comment><comment><USER5> Employees "would be paid a week of severance" \- I haven't gone through something like this, but that seems low. I know when the money runs out it runs out, but I hope employees weren't totally blindsided...

<comment><USER6> Having worked in early stage angel funded startups, I am impressed they are doing severance.

<comment><USER7> This wasn't an early stage angel funded startup. They had 200m+ in funding.

</comment></comment></comment><comment><USER8> Those of us who own their robots are currently looking for ways to save them. Yesterday, the Vector Robot SDK was updated with some of the changes they had planned to release in the future.

The servers are still up; presumably so they can keep selling their existing stock for the conceivable future. But the full promise of functionality for Vector will never arrive.

<comment><USER9> That's good to hear. I wonder what happens once the stock is all sold. Do you think they'll release the source?

<comment><USER8> I think it's extremely unlikely; when has any of these companies ever released the source to their products?

Also, from my experience, Anki was really good with the security behind Vector. He's so locked down that they'd have to officially release a firmware just to provide the functionality to load alternative firmwares or access other services. And with SSL you can't MTTM any of his connections.

I just don't see them having the resources to do anything more useful at this point.

</comment></comment></comment><comment><USER9> The build quality of their "toys" has always been extremely high perhaps to a fault. Think Apple-like materials, design and packaging. Sure, they weren't 'cheap' to purchase, but if you actually owned one of their toys, you didn't feel like you were overpaying.

Both the children and adults who have interacted with Cozmo (in my case) have been genuinely captivated by the "Wall-E" like personality, and how fun their little desk companion toy can be.

This is actually really sad news. With everyone being laid off, it doesn't look like there's going to be some sort of angel acquisition by Apple or something either.

:(

</comment><comment><USER10> My kids love the race tracks, Overdrive. I'll be looking to scoop up some stuff on clearance.

<comment><USER11> Honestly the toys they made are good, however they are all app/cloud connected. I hope the tracks keep working...

<comment><USER12> Makes me wonder how much of the logic was in the cars themselves. I'm guessing not much. Might be a fun weekend project to try to hack though

<comment><USER13> The car's on-board processor has enough logic to follow the track lines hidden under the track surface. The BTLE connection to the car is used to control speed, change lanes, and trigger lights. It also is used to 'drive' the car in some cases if needed.

</comment></comment></comment></comment><comment><USER14> Such a shame. I've worked with a couple of Anki's former DevOps engineers (lucky to have been able to hired one) and they are top notch.

My gut tells me that AI toys weren't the end game, since it's such a low margin space, but just a way to get there and they ran out of runway before they could reach that point.

</comment><comment><USER15> Previous discussion on the same topic - [https://news.ycombinator.com/item?id=19782394](https://news.ycombinator.com/item?id=19782394)

</comment><comment><USER16> I wonder if they will release the full source code so that the developer communities around the world can start improving Vector's capabilities.

</comment><comment><USER17> Honestly their toys always seemed really cool, but I'm surprised this didn't come sooner. They were _really_ expensive, which was justified by how advanced the tech was sure, but to a certain point most people just don't want to spend that much money on a toy

</comment><comment><USER18> So sad, just bought a Cozmo a few days ago and today it arrived. It is a great toy, I like it a lot already! What a shock to now see this in the news :(

</comment><comment><USER19> Dang, I was looking forward to buying their new robot, Vector. We have a Cozmo, and my kids really enjoyed it.

</comment><comment><USER20> I was so upset that my favorite free flashcard program was shutting down.

</comment><comment><USER21> Didn't they _just_ release a new device? This seems shocking.

</comment><comment><USER22> I was really concerned when I saw that headline. I thought that the Anki Spaced Repetition Software (SRS) website was shutting down (it's not). Those little robots are cute, but I think Anki is much more useful to me.

<comment><USER23> Can we change it to say "Anki robotics"? I was similarly worried.

</comment></comment><comment><USER24> My heart almost skipped a beat thinking it was Anki SRS. Infinitely more useful than another VC vaporware.

<comment><USER25> Selling physical toys is about as far as you can get from "vaporware"

<comment><USER24> $200 million funding and $100 million sales in a non-SAAS world (not profits) is vaporware in my book.

<comment><USER26> How selling physical products is vaporware?</comment></comment></comment></comment>


Report: police sharing intelligence on activists with gas industry - <AUTHOR> http://stateimpact.npr.org/pennsylvania/2014/10/08/report-police-sharing-intelligence-on-activists-with-gas-industry/

<comment><USER2> Eh, this isn't isolated to the gas industry. The whole premise of CISPA is the sharing of intelligence in a _bidirectional_ manner. Hell, _Intelligence Sharing_ is part of the name!

Cooperation between LEOs and the gas industry is neither new nor unique.

Now, that said, employing public resources (personnel and otherwise) for wild goose chases is my main concern. I won't get into an argument about civil liberties, but there is a very large amount of resources devoted to investigations that lead no where and pointless harassment of peaceful individuals.

Police sharing intelligence implies that police were wasting time investigating peaceful individuals, and as such this enables private industry to otherwise penalize such individuals.

Furthermore, imagine, for a moment, an environment where protesting increased your car insurance. This happened transparently and automatically, and you have no recourse. Your rates just suddenly went up for an unexplained reason. And you didn't even use your car before, during, or after protesting.

This is what frightens me, because it's plausible. The public sector now acts as an information broker -- a steady stream of data about you is flowing towards private networks, and you have no recourse to defend yourself.

<comment><USER3> They would appear to be investigating the source of some pipe bombs, although it seems to be an open question where these come from:

> There have been instances of hazardous materials– including pipe bombs– > being found near gas drilling sites, but the incidents have not been linked > publicly to environmental activists.

<comment><AUTHOR> They have a history of harassing peaceful protestors. The link near the end of the article is to an instance where they clearly harassed innocent environmental activists, to the point where the Governor apologized and fired the contractors involved.

Actually, that link seems broken; the story is here: [http://stateimpact.npr.org/pennsylvania/2015/01/22/anti- dril...](http://stateimpact.npr.org/pennsylvania/2015/01/22/anti-drilling- group-settles-surveillance-litigation-with-state/)

</comment></comment></comment><comment><USER4> One perspective on fracking: [http://www.publicintegrity.org/2014/02/18/14235/drilling- rav...](http://www.publicintegrity.org/2014/02/18/14235/drilling-ravages- texas-eagle-ford-shale-residents-living-petri-dish)

</comment><comment><USER5> Error 503 Service Unavailable

Service Unavailable

Guru Meditation:

XID: 1398260889

Varnish cache server

<comment><USER6> I get that too. Here's the cache: [http://webcache.googleusercontent.com/search?q=cache:d8CrZiI...](http://webcache.googleusercontent.com/search?q=cache:d8CrZiIs7LAJ:stateimpact.npr.org/pennsylvania/2014/10/08/report- police-sharing-intelligence-on-activists-with-gas- industry/+&cd=1&hl=en&ct=clnk&gl=us)</comment></comment>


Has Windows 8 killed web games by not supporting plugins? - <AUTHOR> http://whatgamesare.com/2011/09/windows-8-plugin-woes-questions.html

<comment><USER2> You don't necessarily need plugins to make web games. The best replacement for Flash for web games that I've seen so far is WebGL (check out Angry Birds on Chrome). The problem is IE9 doesn't have WebGL support, and neither will IE10.

So yes, I guess web games on IE are dead going forward, but it's only Microsoft's fault for rejecting WebGL. But I'm sure developers will continue to make WebGL games for 60%+ of the browser market (or more going forward) for Chrome, Firefox, Safari and Opera.

</comment><comment><USER3> I think it will be more likely that this decision will kill any market share that IE has left.

</comment><comment><USER4> I thought Windows 8 / Internet Explorer 10 was only removing plugin support in tablet mode. i.e. still supporting plugins (including Flash) in traditional desktop mode.</comment>


Harvey Wrecks Up to a Million Cars in Car-Dependent Houston - <AUTHOR> https://www.wired.com/story/harvey-houston-cars-ruined <comment><USER3> Could someone explain to a foreigner why is there so much damage in US areas regularly hit by hurricanes?

Would making the river infrastructure hurricane proof be cost ineffective? Or is it a problem of lack of investment in such infrastructure? I mean, we always hear about some breached levees so I suppose some infrastructure is in place but seems not to be up for the job. Would it be possible and cost effective to make all city like Huston hurricane proof?

<comment><USER4> It suffered 50+ inches of rain (19 trillion gallons of water) in a short period of time. This is the most rainfall in US history. There are things you can do to mitigate flooding, but this was a very extreme event.

<comment><USER5> We just hope this kind of thing stays as extreme and unlikely in the future too. :(

</comment></comment></comment><comment><USER6> when floods wreck cars, 'refurbished' cars seem to magically show up in used car lots far away. Especially those from fleets in car dealerships that have a distribution channel. [https://www.autotrader.com/car-news/beware-of-flood- damaged-...](https://www.autotrader.com/car-news/beware-of-flood-damaged- cars-196494)

</comment><comment><USER7> Maybe they should take some of that 180 billion and build a transport system.

<comment><USER8> It's a 100 x 100 mile area. I grew up there and drove 5 miles to high school, through sprawling neighborhoods.

Retrofitting a transport system to replace the need for cars is virtually impossible.

<comment><USER9> > Retrofitting a transport system to replace the need for cars is virtually > impossible.

This is a very pessimistic take on our capabilities.

Retrofitting modern (past century technology) transport systems onto cities that are a ~ 1,000 years old is things that many cities have managed to do. Almost any capital city in Europe would make a good example.

Can you elucidate on why doing it in Houston is 'virtually impossible'?

> It's a 100 x 100 mile area. I grew up there and drove 5 miles to high > school, through sprawling neighborhoods.

TFA suggest that a million cars within the Houston Metropolitan Area were destroyed. According to wikipedia this is ~ 4,300 sq km.

You've suggested that Houston is 100x100miles ... which is about 25,000 sq km.

You can't both be right.

For reference, Sydney metro area is estimated at around 12,000 sq km - <USER2> times the size of Houston. Australia's renowned for low population density (equating to relatively high cost of public transport infrastructure per person) ... and yet.

<comment><USER10> > Retrofitting modern (past century technology) transport systems onto cities > that are a ~ 1,000 years old is things that many cities have managed to do. > Almost any capital city in Europe would make a good example.

These cities have always been pretty dense. Density around transit stop is the critical dimension of successful transit systems. Building infrastructure is a pretty trivial problem in comparison of changing the density distribution of a whole metropolitan area.

It can be done, however, with enough political clout. Many American cities have a big advantage: large straight streets. Car lanes can be converted to transit lanes for cheap, but it's politically very hard to do.

</comment></comment></comment></comment><comment><USER11> On a parallel thread, August just turned over to September and rent is due in Houston: [https://news.vice.com/story/harvey-flood-rent- undocumented](https://news.vice.com/story/harvey-flood-rent-undocumented)

<comment><USER12> Wow! 400k illegal aliens in Houston. Note he is an electrician; a solid trade, immune from illegal labor (who only take the jobs no one wants). Anyway, he will have plenty of work soon enough.

</comment></comment><comment><USER13> Good thing used cars are cheaper: [https://news.ycombinator.com/item?id=15076441](https://news.ycombinator.com/item?id=15076441)

</comment><comment><USER14> I wonder what effect it will have on car loan securitization where the gain in values is only temporary. The used car market was already in oversupply.

</comment><comment><USER15> The name of the thread doesn't really match the article name now, does it.

<comment><USER16> Further, other than a handful of metro areas the entire country is "Cartown."

<comment><USER17> The article does say why they are giving Houston that title.

 _" That's why 94.4 percent of households in the Houston area have cars—1.8 each on average, according to analyst firm Cox Automotive. Only Dallas has a higher percentage."_

<comment><USER18> For non-Americans who are having trouble imagining this, note that the movie "Office Space" was filmed in Dallas. The stop-and-go traffic in the intro? That's every day, twice a day. The only difference between Dallas and Houston is that Houston has even fewer sidewalks.

<comment><USER19> I would think Houston also has worse pollution and more humidity than Dallas.

<comment><USER20> Believe it or not Dallas has worse weather than Houston, just on different axes. Houston is humid 99.9% of the time, hot 75%, and has occasional tropical storm related wind and deluge.

Dallas has ice storms, EF3+ tornados, hail storms, wind storms, full-on snow, and severe thunderstorms - all with regularity. It will cost more to insure your home and vehicle against weather-related mishaps in Dallas than Houston.

Houston tends to have pretty consistent clearing breezes so although there is no doubt more car and industrial emissions it's not clear that the ambient pollution level is any worse than other major cities.

<comment><USER19> I have done a fair bit of traveling. In Houston, I ate lunch, walked out of the restaurant and into the polluted air and basically promptly threw up in reaction to it. I decided I was done and leaving. It may not be worse in your eyes, but it is the worst air quality I have personally experienced.

I said nothing about _weather_ , just humidity. Houston is closer to the coast than Dallas.

I grew up in Georgia and I have lived in Texas. I have some familiarity with the weather of the Southeastern US.

<comment><USER20> > In Houston, I ate lunch, walked out of the restaurant and into the polluted > air and basically promptly threw up in reaction to it. I decided I was done > and leaving.

Strange, I've never seen or heard of anyone losing their cookies over Houston pollution before. I lived there for 11 years, was an endurance athlete there, and have lived in Austin for 22. I wonder what the circumstances were.

> It may not be worse in your eyes, but it is the worst air quality I have > personally experienced.

I think you haven't seen real air pollution then. I've choked in Los Angeles in the '70s, had to take a bath after being outside in Pittsburg in the 60's, and seen the choking effluent that cities like Gary, IN and Erie, PA had before the EPA got geared up. That's not to mention places that I haven't been, like Beijing, or Shanghai, or Sao Paolo, or even Tokyo at times. I think it is an exaggeration to claim Houston is any more polluted than most major cities.

<comment><USER19> I wasn't claiming it was more polluted than most major cities. I only suggested it was probably more polluted (and humid) than Dallas. So, you are reading in things I did not say.

</comment></comment></comment></comment></comment></comment></comment></comment></comment><comment><USER21> "HARVEY WRECKS UP TO A MILLION CARS IN CAR-DEPENDENT HOUSTON"

</comment><comment><USER22> trump needs to order a fleet of busses from tesla.

<comment><USER23> lol</comment></comment>


Dear HN: If you could take a free online class in anything, what would it be? - <AUTHOR>

<comment><USER2> I see lots of free classes on the technical side of things such as math, science, learning to program, etc.

I would love to learn more about the financial side of things and I don't mean just micro- and macroeconomics. A class that is more practical that teaches you about valuation, reading a statement, marketing, negotiations, etc.

</comment><comment><USER3> A class in web development just explaining what everything is and what it does. There are a million different acronyms for all the different technologies out there. I look up stuff when I can, but more often than not I just end up more confused.

</comment><comment><USER4> Some sort of conflict resolution - e.g. a guided roleplay.

</comment><comment><USER5> I'm not sure. Maybe something like law.

</comment><comment><USER6> Permission Marketing

</comment><comment><USER7> Chinese -- it'd be pretty impressive if anyone could pull that off well in a free online class.

<comment><USER8> Memrise.com is pretty awesome.</comment></comment>


How to get a content piece to go viral? - <AUTHOR> https://capitalandgrowth.org/questions/1124/what-are-some-good-booksresources-on-learning-how.html?src=hn-2018-8-30 <comment><USER2> I don't think there is formula to do it. But yes if you keep trying the best practices then the chances are there that it go viral.</comment>


Instacart tweaks tipping system after tip-baiting outcry - <AUTHOR> https://www.theverge.com/2020/6/5/21281910/instacart-tip-baiting-changes-congress-inquiry-exploitation-covid-19 <comment><AUTHOR> 'Instacart is adjusting how it handles customer tips following the announcement last week of a congressional inquiry[1][2] into the practice of tip-baiting, in which Instacart allows customers to promise big tips for shoppers only for those customers to later rescind the tip after the order is dropped off.

'Instacart now says it will shorten the window a customer can alter their tip from three days down to 24 hours. It's also now requiring customers leave feedback for removing tips and pledging to deactivate any customer who "consistently and egregiously engages in this type of behavior." The company claims "only 0.25 percent of orders had a tip adjusted after 24 hours," and that, "less than 0.5 percent of orders have tips removed after delivery." Instacart is also expanding its in-app cash-out feature to include tips, so shoppers can now receive the extra earned money from an order 24 hours after a completed order.'

[1] [https://www.theverge.com/2020/5/29/21274540/instacart-tip- ba...](https://www.theverge.com/2020/5/29/21274540/instacart-tip-baiting- deceptive-shoppers-ftc-investigation-congress)

[2] [https://www.schatz.senate.gov/imo/media/doc/Letter%20to%20In...](https://www.schatz.senate.gov/imo/media/doc/Letter%20to%20Instacart%20re%20tip%20baiting%205-28-20%20Final.pdf)</comment>