Pascal's Apology, or why computer science is complicated - <AUTHOR> http://carlos.bueno.org/2012/08/pascals-apology.html <comment><USER2> "I started writing Lauren Ipsum by looking for ideas that I understood well enough to explain to a nine-year-old child."

Three decades ago I started a company that created a word processor. As part of our usability testing, we gave our little 100 page manual to an eight year- old boy and told him to write a letter. A couple of hours later he finished and we pronounced our endeavor a success. Even our customers were happy with how easy it was to use.

For our next release we produced a real manual -- 400 pages long. We were inundated with complaints about how difficult our product was to use now. Lesson: keep the story simple. Make the advanced features emergent and discoverable.

</comment><comment><USER3> Maybe I'm that ahead of the curve, but I understood inmediately what an algorithm that "takes a Bernoulli sequence with p != 1/2 and outputs another B. seq. with p = 1/2" is. Or perhaps the author chose a wrong example.

If anything, it shows that this field is mature, and has progressed to a more general vocabulary. It's still light years behind other kinds of engineering, IMO.

<comment><AUTHOR> It's not at all accessible to children, at least compared to what it could be. I've been writing code for money for 20 years and it took me a long time to understand that paragraph. It is concise, but it's not clear. And worse there is no indication of just how important this clever little algorithm is.

<comment><USER4> Writing code is very different from computer science. Also, computer science isn't really a young field, it is a new(ish) branch of mathamatics.

</comment></comment></comment><comment><USER5> Jargon is wonderful _once you've learned something_. Then it lets you communicate concisely with others who share the same working knowledge.

<comment><USER6> More specifically, jargon is wonderful once you join a community that uses it. Much like any other language, its lifespan is measured by how many speakers it has. As a term, it is not significantly meaningful from "pidgin" or "creole" or "dialect" or "slang".

</comment></comment><comment><USER7> I'm a developer, a good one people say, but I'm not a computer scientist, or any kind of scientist, nor a mathematician (and my CS degree won't change that)

I get code, and I get design, but I didn't get that example without the (very interesting) simplified explanation

Bought the Kindle edition (price is very reasonable), will let you know what I think of it for grown ups...

<comment><USER8> I'm with you--got a BS in EE&CS, and an MS in Software Engineering, but I can't really honestly say I'm an engineer, electrical, software, or otherwise, nor a computer scientist. Maybe a computer scientician... And while I did very well in my studies (many, many years ago) and am pretty highly compensated for my work with computers, I needed the explanation too.

</comment></comment><comment><USER9> I really see programming as an art first and then a science, just like music.

Art comes from creating something new and stepping outside the box while science is about explaining some existing thing and defining the box to put it in. By studying music history we can see that new styles, harmonies and figures almost always came before the theory that explained them. This is much like new languages, frameworks or patterns coming out and then papers being written about them.

During the middle ages you would hear almost only intervals of an octave or a fifth. Then with classical music came the third and the sixth intervals and the second and seventh intervals only made it a few centuries later. Music as a theory evolved over thousands of years. Only recently did it explode with jazz trying to find every single way to bend that theory.

The brain cannot easily play with a concept it has no single-word name associated to. Right now CS is full of concepts described by mini-phrases and no clear hierarchy for all of these concepts. Music theory by contrast can be entirely described starting from the major chord. Every single concept (as far as I know) has it's proper place in a tree structure with the major chord as its root element.

It's ironic how programmers dread spaghetti code yet ended up with a spaghetti computer science. It might also not help that the industry is plagued with code smells.

In the end, by comparing harmonies to data structures, melodies to code flows and multiple voices to concurrency, I believe its mostly all the same to the brain. A musical score is nothing more than source code for the human brain to read and interpret.

<comment><USER10> > Art comes from creating something new and stepping outside the box

That's a big part of science, too.

<comment><USER9> That's the art of science. :)

</comment></comment></comment><comment><USER11> On another page [1] the writer says: "Children in Finland go to school year round". Why would he say that? Did he just pick a random far-away country to say a strange (but untrue) thing about? Or does he really think that children in Finland go to school year round, even though a little googling would reveal otherwise?

[1] <http://www.laurenipsum.org/mostly-lost>

<comment><AUTHOR> In a word, yes. It's a running joke in the book, eg children in Finland start reading at 12 months. Children in Finland eat all their vegetables, etc. It's intended to poke fun at fretful American parents and the things they say to motivate children. I've gotten more outrage over this one sentence _from Finns_ than anything else in the book. :/

</comment></comment><comment><USER12> > _This algorithm works because no matter what the bias is, the odds of > getting a Heads then Tails will always be exactly the same as the odds of > getting a Tails then Heads._

That may be easy to state, but I don't see it at all as a self-evident Truth. Hence the need for jargon, in order to actually come up with proofs in the language of mathematics.

<comment><USER13> The odds of getting Heads on any given flip are always (x)%, regardless of the previous result. Likewise, the odds of getting Tails is always (100-x)%. So you will get HT with probability (x)% * (100-x)% which might be as high as 25% with a fair coin but might be much lower. _Regardless_ of how small the probability, it is _exactly_ the same as getting TH which is (100-x)% * (x)%.

edit: typos

<comment><USER14> Is something like this sufficient as a proof? It's so natural and easy, yet convincing and accurate, that I have hard time believing it. :) Even if it's just an explanation it's still awesome. How I wish I could find materials teaching math ideas without relying heavily on math language! (And no, because I'm not going to contribute to the field I don't really need to know that language... Except I need, because it's the only way to obtain what is useful to me, however uncomfortable it is for me...)

<comment><USER4> That is a completely valid and rigorous proof.

The difficulty with reading more "formal" proofs is that they try to make each statement as consise as possible, because it makes it easier to manipulate the results, and hold more of the proof in your head at a time.

For perspective, consider the quadratic equation. This equation was first discovered in 628 AD, India. An English translation (from 1817) reads: "To the absolute number multiplied by four times the [coefficient of the] square, add the square of the [coefficient of the] middle term; the square root of the same, less the [coefficient of the] middle term, being divided by twice the [coefficient of the] square is the value"

Or, as modern mathematicians would right, x=(sqrt(4ac+b^2)-b)/2a.

The equation is slightly different for two reasons. First, it applied to equations of the from ax^2+bx=c, as apposed to ax^2+bx+c=0, so the sign of 4ac is inverted. It also misses the second answer provided by the '±'.

The original paragraph form is probably easier for someone unfamiliar with anything beyond arithmetic, however the modern form is far easier to reason about, and use to those who invest the time to learn the notation.

<comment><USER14> > The original paragraph form is probably easier for someone unfamiliar with > anything beyond arithmetic

Isn't this because of the fact that at the time (628 AD as you say) there wasn't that much to be familiar with beyond arithmetic? (I don't really know the history of maths, just curious.)

> and hold more of the proof in your head at a time

Is it really the case? I mean that no matter with which notation you start with, you need to parse and evaluate it mentally to convert it into terms you actually think with.

I can see that for maths 'natives' it is helpful, because their mental models are very closely tied to the formal notation. But for me mathematics is a foreign language, it seems that I think in slightly different terms and this succinct notation makes it harder for me to actually understand what it is really about. (I don't mean your example specifically - it's still well inside my comfort zone).

As a programmer I do struggle for "math literacy" because I have to. I need to be able to read proofs, understand some concepts to be able to use them and to know when I need them. The problem is it's not natural for me. Yesterday I found here on HN a book that just may be exactly what I'm looking for: <http://greenteapress.com/thinkstats/html/index.html> (didn't have time to read it yet, but it looks promising).

> who invest the time to learn the notation

I think I said it before but maybe it's worth noting explicitly. I am somewhat familiar with the notation, I consider myself 'literate'. But I'm far from fluent and I probably never will be. Similarly, I can read and write cyrillic script (with pen and paper). But it takes me more than twice the time to read russian in cyrillic than reading the same text written with latin letters. I don't need someone to translate russian to english for me. It's just the character set that is a problem. I think it's very similar to what I experience with math.

</comment></comment></comment></comment></comment><comment><USER15> Intel's Ivy Bridge chips use that technique of eliminating bias to ensure true random numbers for the RdRand instruction (it gets random data from thermal noise).</comment>


Show HN: Prototype your Slack bot - <AUTHOR> https://walkiebot.co/ <comment><USER2> Didn't even know you could do footers in attachments. Well done!

</comment><comment><USER3> awesome and super useful when designing advanced bot interactions

</comment><comment><USER4> Cool stuff ;)</comment>


Hacker News London meetup, Wednesday 23rd Oct - <AUTHOR> http://www.meetup.com/HNLondon/events/145037122/

<comment><USER2> I will be speaking there:

[http://bit.ly/GTaE5X](http://bit.ly/GTaE5X)

<comment><USER3> Really nice to recognize a name here. Such a shame I won't be able to attend this, I have to return to Portugal on the 17th.

I heard some tales of you in Fullsix when I worked there and would love to get to know how it's going on SO. Best of the luck for the presentation.

<comment><USER2> I was in Fullsix in May giving the long version of this. Were you attending?

<comment><USER3> Oh no, didn't even know that happened.

</comment></comment></comment></comment><comment><USER4> This is in the middle of LinuxCon Edinburgh, a huge Linux conference being held in the UK for the first time in a long time.

<comment><AUTHOR> Edinburgh is on the other side of the country. HNLondon is popular, but we don't quite have that much pull.

<comment><USER5> Not just on the other side, but 400+ miles away, and in a different country ;)

</comment></comment></comment><comment><USER6> This is a great event. I'd highly recommend it to anyone in the London area.

</comment><comment><USER7> Really excited to come along as I've not been to a tech meet up in London before. First time being around likeminded others was at WWDC and that was awesome!

</comment><comment><USER8> I was skeptical at first, but this is a good event. Worth the money.

EDIT: If you want pizza, though, get there early.

</comment><comment><USER9> Interesting.. Woz is giving a talk that same day, in the morning, in London @Appsworld.

<comment><USER10> I'm heading along to that, from Dublin, and I'm thinking I might stay an extra day in order to go to this meetup.</comment></comment>


One meteorologist explains why he won't fly again - <AUTHOR> http://www.salon.com/2013/09/30/one_meteorologist_explains_why_he_wont_fly_again/ <comment><USER2> What some of the other comments here seem to miss is that he isn't suggesting to replace air travel with other modes of transport. He suggests cutting back on unnecessary long distance travel. And if you have ever seen scientists' travel schedules, you might be inclined to agree. I find it bizarre that those people who should be the first to understand climate change are among the most active producers of CO2.

As a grad student I once flew half way around the world (18 hours + 2 hours flight time) to present a paper to a room of 10 people who had traveled similar distances to get there. Because the paper was more or less mistakenly assigned to a "robots for hazardous environments" session, exactly none of the people in the audience cared. And because I was last to present in a session of 6 presentations and the 5th presenter didn't show up, I started mine ahead of schedule. A few acquaintances who wanted to stop by just to see me present came in just after I finished. Nobody gained anything from this 15 minute presentation.

If I had skipped the trip, my paper would not have been included in the conference proceedings. Publishing papers at conferences is one thing you have to do to be considered a successful scientist and this was only my second conference paper. The story is only one anecdote, but the entire system of science is built around encouraging people to travel long distances frequently. It's stupid.

<comment><USER3> Similar story. When I was grad student, I was flown half way around the world (Oregon -> Italy) to present someone else's paper (!) because they were feeling ill. I had only the most rudimentary knowledge of the contents, since it was such a last minute affair. So, as in your experience, the presentation was hardly worthwhile at all, much less the expense (environmental or financial) of sending me, in aggregate, all the way around the world.

</comment></comment><comment><USER4> He won't fly? Or he won't travel?

Big, big difference. Because flying is one of the MOST efficient ways to travel. FAR more efficient than even taking a bus.

> If more would cut down on just one long-distance flight per year, he > maintains, that would also have a major impact.

That's terrible advice because people will drive instead. And adding "long- distance" makes the advice worse since long-distance flights are more efficient than short ones (most of the work is getting in the air, not staying there).

The ONLY was to cut down CO2 emissions is nuclear power plants. Nothing else is practical. If you care about CO2, and you have the opportunity, lobby to have a nuclear plant installed near you[r city].

<comment><USER5> I don't think you're right about efficiency. Trains and boats are definitely more fuel efficient than flying, and cars are close. The figure for planes is about 90 passenger-miles per gallon, for fully loaded (55 people) deisel buses it's about 330. (All from this lovely article [http://en.wikipedia.org/wiki/Energy_efficiency_in_transporta...](http://en.wikipedia.org/wiki/Energy_efficiency_in_transportation))

Of course it depends on your stopping and starting.

<comment><USER4> See: [https://en.wikipedia.org/wiki/Energy_efficiency_in_transport...](https://en.wikipedia.org/wiki/Energy_efficiency_in_transportation#US_Passenger_transportation)

For more realistic figures rather than theoretical maximums.

And I especially found it interesting to note that as typically used, cars are better than busses.

<comment><USER6> I think buses are better than cars, for inter-city travel. Wikipedia's numbers are probably more relevant to transit buses (i.e. the ones local governments run, which are often empty). Greyhound doesn't run uneconomic routes.

<comment><USER7> Bicycles are really healthy, cost little to acquire, are easy to repair, last for ages, and work reasonably well in most climates.

 _the bicycle is one of the most efficient forms of transport... half the energy per unit distance of walking ... converts to about [there are 2 claims in wikipedia, 732 and 879 mpg]_

I strongly suggest any hackers (aging and pot-bellied or otherwise) give long distance cycling a go: it's truly pleasurable and great for your brain! I spend much of my 20s doing this in foreign countries.

<comment><USER8> > work reasonably well in most climates.

If you like to be boiled in the summer and frozen in the winter, not to mention having to cycle on icy roads with no shoulder and sixteen-wheelers bearing down on you.

Anyway, if you do cycle, please don't make a habit out of blowing past pedestrians at full speed, and think twice about riding on the sidewalks.

<comment><USER7> Perhaps consider moving to a less automobile-obsessed culture and a better climate.

<comment><USER8> Your snark aside, I don't cycle. I walk. Mainly, I'm concerned with getting knocked down by a cyclist who thinks that sidewalks are a wonderful place to go full speed without having to worry about anyone else.

<comment><USER7> Do you think perhaps they may have a similar concern regarding significantly larger mass vehicles moving at higher speeds some distance to your side?

<comment><USER8> > Do you think perhaps they may have a similar concern regarding significantly > larger mass vehicles moving at higher speeds some distance to your side?

So they're justified in acting recklessly around me because others act recklessly around them? If it's that much of a problem, they should walk.

</comment></comment></comment></comment></comment></comment></comment></comment></comment></comment><comment><USER9> There's an interesting response to this, in which the author argues that "for the sake of the planet, please fly!":

[http://qz.com/131024/its-ok-to-have-a-big-carbon- footprint-a...](http://qz.com/131024/its-ok-to-have-a-big-carbon-footprint- and-pay-others-not-to/)

<comment><USER10> > [http://qz.com/131024/its-ok-to-have-a-big-carbon- > footprint-a...](http://qz.com/131024/its-ok-to-have-a-big-carbon-footprint- > and-pay-others-not-to/)

It's bit like saying "it's ok to each caviar at charity dinner". It may be right economically but it's very morally shady if costs of caviar and benefits it brings to fundraiser aren't carefully, unambiguously calculated.

</comment></comment><comment><USER11> This guy is reducing his quality of life to save the environment (or so he believes). That's more than most of us are willing to do, and that's why his sacrifice is futile. He's the exception that proves the rule. I don't think _any_ civilization has ever voluntarily reduced its resource consumption. Adapting to climate change or reversing it with geoengineering is probably easier than changing human nature.

<comment><USER12> You can fly and drive all the miles you please knowing that you will never impact the planet as much as someone who has 2 or God forbid more kids. Because there is one and only one thing that will save the planet, and that's fewer us.

<comment><USER13> How haughty to assume that the onus is on us to "save" the planet. How absurd to also assume that the only way we could accomplish this is by some quota of human beings.

<comment><USER12> Oh the planet will do fine without us, but using the commonly accepted meaning of the phrase to mean preserving a familiar ecosystem, then yes, the only was todo that is to consume less. If we abandon modern tech that will happen anyway since we rely on industrial farming.

So we can reduce our load on the ecosystem in a managed way likeChina did, or we can have it forced upon us, but it is going to happen.

</comment></comment></comment></comment><comment><USER14> Not at all what I expected. But this feels like the very definition of a power law problem: the few people out of the human population who fly regularly have so much more impact than the rest combined.

</comment><comment><USER15> This is South Park material. I would love to see an episode with ManBearPig, Al Gore and the crying meteorologist.

<comment><USER16> And this is the type of poisonous, vacuous comment that makes Hacker News a worse place.

If you want to make an argument that Climate Change is not an issue: Make it. If you want to say that this person's reaction is irrational, make that argument. Don't be snide and claim "This person's emotional response is obviously stupid, and he deserves to be mocked without justification".

As it stands, we have no idea why you feel that this is stupid (though your reasons are probably crap). You're simply being offensive, and not adding anything to the discussion. People who disagree with you are disadvantaged, because you've made no actual points; and so you can dodge any criticisms with "Where did I say that?". Which of course, is the main point, you haven't said anything. You're just being an ass.

<comment><USER15> Man-made climate warning is most likely a hoax that fuels a multi-billion- dollar industry and is used, among other things, to erect protectionist barriers against Chinese and Indian cars. So there are extremely powerful vested political and economic interests to ensure that there's no possibility of an honest debate, even to the point of falsifying data I would suspect (never mind the indoctrination of young children across most of the western world).

Even if that weren't the case it would still be pointless to worry about it as trying to change people's behavior outside the marketplace can only be done with totalitarian methods, which is exactly what environmentalists propose. Not to mention, since this is Hacker News after all, that I would love to see CO2 concentrations go up 50 times to reach those recorded during dinosaurs' time (sorry, too lazy to check exact era), as a much denser atmosphere would allow almost car-sized airships to be built, or even human flight with wings and how cool would that be.

Environmentalism is the new communism and Gaia-worshiping is a religion with Al Gore as its main tele-evangelist. The guy has even set up his own company selling carbon credits. I am certainly not going to write a lengthy exposition identifying the errors in Benn Hinn's theological doctrine. Ridicule saves time.

<comment><USER17> > Man-made climate warning is most likely a hoax that fuels a multi-billion- > dollar industry and is used, among other things, to erect protectionist > barriers against Chinese and Indian cars. So there are extremely powerful > vested political and economic interests to ensure that there's no > possibility of an honest debate, even to the point of falsifying data I > would suspect (never mind the indoctrination of young children across most > of the western world).

What you present here is, as far as I can tell, an argument that there are (well-monied) interests that stand to gain from having people believe in AGW. That is a valid point to make, but it does nothing to prove the conspiracy that you sketch. Do you have any proof?

You go on (sorry, it's cumbersome to quote on my phone) to suggest that the fact that there are people who take a religious view towards environmentalism matters for the debate. I agree to a certain extent that this is a problem, but the solution is simple: don't listen to the enviro-religious people. Listen instead to the science.

<comment><USER15> Even assuming that man-made global warming is true and that high concentrations of CO2 is a bad thing, what does science tell me that's really actionable? Coordination is impossible in prisoner's dilemma type games. No solution, no problem. The only way to "solve" the "problem" is with world-wide totalitarian measures which would produce untold misery as a side effect. I 'd much rather have the sea level go up 2 meters. The crying meteorologist is to me on a par with the British young woman who had an abortion "for the environment". To recap: powerful interests, alarming indications of intellectual fraud (e.g. accusations of data massaging, gradually speaking more of "climate change" than "global warming"), nothing to do that's compatible with me pursuing my interest, yes selfish interest - is there another kind? -, in a market economy. Case closed for me.

</comment></comment></comment></comment></comment><comment><USER4> He says he recycles.

What does he recycle? Because only metal is worth recycling, everything else is not worth the extra pollution and water.

<comment><USER18> Combustible garbage can be usefully turned into electrical energy.

<comment><USER19> The city I grew up in, did just that with all of its garbage in the 60s/70s and had to shut down in the 80s because it was a net loss once the full cost of exhaust scrubbers, disposal of whatever they scrub out, etc, was taken into account.

They were having profitability issues as it was once labor costs, boiler certification and related costs, maintenance, and ash disposal were factored in, so it didn't take much environmental cleanliness regulation cost to wipe out any profit from the incinerator.

Or rephrased, you can burn trash to make X units of electricity, it'll just n*X units of electricity to operate the plant, pay the workers, clean the fumes from the smokestack, maintain the boilers, operate the facility... Some factors are O(1), some O(n), some probably O(polynomial) if not exponential so simply making a bigger facility doesn't help (and a bigger facility means burning more diesel to haul the trash, no free lunch...)

<comment><USER20> You realize that was fifty years ago, right? This is like saying computers are impractical because their vacuum tubes require too much power - here in the 21st century, Sweden has actually run out of combustible garbage because it's working for them. They now have to import garbage as a fuel for power generation.

<comment><USER4> It works for Sweden because the population does the work for them.

They have like 10 different bins for garbage [http://blog.liu.se/rhiannonbristowstagg/category/life-in- swe...](http://blog.liu.se/rhiannonbristowstagg/category/life-in- sweden/page/3/)

So the power plant hardly needs to do any sorting - all the combustibles are already separated (which means much less ash). Of course no one counts the work of the population when factoring costs.

<comment><USER18> In fact, machines sort garbage better than humans. In the UK, we're moving away from having people do lots of sorting, towards having everything "recyclable" going into one giant bin. The factory then sorts that into metals, burnables, glass & whatever... it's cheaper, easier and better for everyone.

<comment><USER19> Do the machines shred? That would be an interesting advantage to machine sorting, shove an old car thru the shredder, and the glass chips go this way, the metal chunks go that way, and the plastic pieces go this way.

Maybe we don't often throw cars into the residential trash, but I could see this working with kids toys, or plastic bottles with metal caps.

<comment><USER18> Here's a good video of a modern plant: [http://www.youtube.com/watch?v=rJzqP5pnOF0](http://www.youtube.com/watch?v=rJzqP5pnOF0)

</comment></comment></comment></comment></comment></comment></comment></comment><comment><USER21> Climate change is alarming enough, and has been for long enough that I don't get responses such as these. Wikipedia says a 747 rates 91 passenger-miles per US gallon. We need big changes to the energy supply system that will be incredibly difficult to attain. We don't need irrational responses. The hard problem is to de-couple energy from coal and oil from wealth. Without accomplishing that, air travel won't matter one way or the other.

<comment><USER22> Air travel do matter and there is nothing irrational in doing our best to decrease it. Just because Americans first compare it with cars that is the most inefficient way to travel doesn't mean that air travel is efficient compared to busses, trains or boats. (Also, 91 passenger miles per gallon is slightly less than me and my wife gets when travelling in our Prius together.)

The point is that we have to learn to live with travelling much less. Both me and my wife are scientists, and we have become used to 2-4 intercontinental trips (back and forth) per person and year for conferences and collaborations. That contributes much more to our total carbon footprint than everything else we do summed together. It just have to stop.

<comment><USER21> OK, but that may say more about the limits of carbon reduction in discretionary actions by individual consumers than about air travel as a problem. At some point you have to start transforming the supply balance at a significantly faster pace than demand growth, or you can't make a dent in the absolute components of coal and oil in the energy supply, nor will carbon- conscious consumers like you be able to achieve further savings.

<comment><USER22> We must do both. Of course we need to change how our energy is produced, but we must also decrease the amount of energy we consume at the same time. Otherwise we have no chance to succeed.

And of course I am know very well that what I and my wife do is just a piss in the sea. The point is that it is much easier to argue that you should do your part to decrease the amount of greenhouse gases you are responsible for, and even support legislations that forces you to, if we already have done our part and a little more. It would be much easier for the US to ask China to do something about their greenhouse gases if the US per capita emission wasn't something like 4 times as high as China's.

</comment></comment></comment></comment><comment><USER23> Anyone else get auto redirected from Salon to Candy Crush Saga in the app store (on iphone)?

</comment><comment><USER24> I don't want this to sound the wrong way. I certainly accept human caused climate change and all that. However, I think this is an example of how some people are just too dramatic for their own good and really should avoid quick fire social media tools.

<comment><USER25> I just flew throug SFO last week and what made me sad was the skid marks in the grass reminding me of the recent crash.

<comment><USER24> Right, and that's pretty normal.

</comment></comment></comment><comment><USER26> According to what I assume is a 100% scientific pie chart the leading cause of global warming is fire. So I don't know why this guy is concerning himself with air travel.

[http://i.imgur.com/AvIHovx.jpg](http://i.imgur.com/AvIHovx.jpg)

<comment><USER17> What do you feel that this adds to the discussion? Seriously - if you want to express yourself, please do so in a way that adds to the conversation.

(I realize that this very comment of mine also does not add anything.)

</comment></comment><comment><USER27> We need to throw money at this kind of stuff - [http://www.gizmag.com/eads- voltair-electric-airliner/18988/](http://www.gizmag.com/eads-voltair-electric- airliner/18988/)</comment>


My Big Idea Today: Saturate the Groupon Model - <AUTHOR> http://robisit.com/f8

<comment><USER2> We had a conversation about this on IRC yesterday. Lots of opportunity out there in this space, and all of the groupon clones prove that.

My angle was going international. It looks like it hasn't really caught on in other parts of the world.</comment>


Ask YC:  Is it possible to build a computer display that corrects your vision? - <AUTHOR>

I know that 3D displays exist that don't require special glasses.<p>So maybe this is possible as well? <comment><USER2> The short answer is no. The long answer is, anything is possible. You have to invent it or wait. Whatever you come up with is not going to look like a conventional display.

I'd suggest spending a day with the optics section of a good physics book. I have terrible vision, and both eyes are different. So the first thing _I_ would think about is how to get different light into each eye.

</comment><comment><USER3> I give this a solid "no".

Notice that when you wear glasses, the lenses stay in the same place relative to your own eyes.

The display would need to track your head position continuously in all three dimensions and have some sort of rapidly-changing lens that continuously adjusted which way the light was pointing so that it hit your eyes from the same angles that were caused by the lenses of your glasses.

This might include growing and shrinking the lens as you move closer to it and further from it. Notice the size difference between contact lenses and wearable glasses lenses and extrapolate that to the screen.

Plus, you would get the bizarre sensation of seeing only the screen clearly with everything else permanently out of focus.

All this, and the next person over still can't see it.

Even if this were somehow possible, it's hard to argue that it's a better solution than putting lenses in front of someone's eyes.

</comment><comment><USER4> Correcting vision is about changing where the light lands on the retina in the eye. I don't see how a display can do that, but I'm not a physicist and so will not claim possibility, let alone impossibility.

</comment><comment><USER5> Strictly Guessing, but I would suppose that you could make a "Lens" out of a polymer that would direct different images at each eye, for a given distance of the viewer.

I don't know why I guess about such things though, it' just an interesting problem.

This guess was based on the following: when I was a kid I went to a polymers camp, one of the doctorate candidates students there was working on a covering for LCD screens to correct the distortion at different angles, so it seems possible.

</comment><comment><USER6> You mean to correct farsightedness? One could imagine displaying an image corrected by a real or virtual convex lens, but the farther the "lens" was from the viewer, the smaller the image would have to be (or the larger the display).

Or the lens could be placed closer to the viewer: <http://www.50plushealth.co.uk/index.cfm?articleid=2128>

But if it's that close already, why not just wear glasses?

<comment><AUTHOR> I mean to correct any common vision problem that would make it difficult to see what's on the screen. So this would include not just farsightedness but also astigmatism.

Some people don't like wearing glasses. At least with such a display, they won't need to when using a computer.

<comment><USER7> The problem there is that, even if it were possible, most people do not have the same astigmatism in both eyes... so which eye would you calibrate the monitor to correct for?

<comment><AUTHOR> You would use a special sort of display that would direct a distinct image to each eye.

3D displays that don't use special glasses already do this.

<comment><USER8> You mean these?

<http://en.wikipedia.org/wiki/Autostereoscopy>

You made me google it; I had no idea those existed. At first sight, it looks like it should be able to do what you ask. Geez, it could even diagnose your (short|long)sightedness|astigmatism and recheck it every now and then.

Pretty sweet tech; I hope it gets commercially viable soon!

</comment></comment></comment></comment></comment><comment><USER9> There are a number of computer controlled glasses. Adaptive optics for example:

See: <http://www.wired.com/science/discoveries/news/2006/02/70181>

<comment><AUTHOR> The point of my proposal is to get rid of glasses while using a computer.

</comment></comment><comment><USER10> Try "M-x glasses-mode" in emacs.</comment>


Trump: Post Office loses $1.50 on avg for each package it delivers for Amazon - <AUTHOR> https://twitter.com/realDonaldTrump/status/980063581592047617 <comment><USER2> _"The whole post office thing, that 's very much a perception he has," another source said. "It's been explained to him in multiple meetings that his perception is inaccurate and that the post office actually makes a ton of money from Amazon." _

[https://www.axios.com/trump-regulation-amazon- facebook-646c6...](https://www.axios.com/trump-regulation-amazon- facebook-646c642c-a2d7-454b-a9a9-cdc6e4eaef2c.html)

</comment><comment><USER3> I'm much more worried about the China subsidy and how it allows crap goods sellers to unfairly compete with Americans.

For example: [https://mobile.twitter.com/PollySpin/status/9555543439562219...](https://mobile.twitter.com/PollySpin/status/955554343956221953)

<comment><USER4> So you're saying you prefer these cheap Chinese products be sold first to American merchants, and then resold to US consumers? More American merchants will make money through arbitrage but it's effectively money spent by consumers to subsidize merchants. There isn't any real value being created. And fewer products will be sold, making entry to interesting maker or hobby projects prohibitively expensive.

If I need some cheap diodes and caps, I'll hit aliexpress rather than spend 20x the markup for the exact same product on Amazon.

</comment></comment><comment><USER5> Citation?

Follow up questions:

1\. How much of that is fixed cost that has to be paid (if not by Amazon then by other customers)

2\. How does -$1.5/package for Amazon compare to other shippers? E.g. how much does USPS lose on Walmart?

My understanding is the USPS is structurally designed to lose money as a subsidy to society for communication/interaction over long distances. I'm fully in favor of revisiting whether that subsidy is necessary in the modern internet driven age in which border expansion is not a goal. But, picking on Amazon for using the subsidy as intended doesn't make sense.

<comment><USER6> Your second question is the key: the USPS exists to encourage business. It loses money on most, if not all, package plans it has with businesses. It does not seek to gain profit.

<comment><USER7> The USPS does not exist to encourage business. It should not be losing money on business plans. The USPS is solely funded, so losing money on a major part of their business is just bad business

</comment></comment></comment><comment><USER8> One thing that has always been a worry is the budget deficit the postal service runs. I think more should be done to examine where costs are going, where profits could be made, or expanded. Quoting from their 2017 financial report: "The Postal Service reported a net loss for the year of $2.7 billion" [0] That use to be $8 billion ten years ago, so perhaps things are getting better...

[0.] [https://about.usps.com/news/national- releases/2017/pr17_069....](https://about.usps.com/news/national- releases/2017/pr17_069.htm)

</comment><comment><USER9> [https://www.snopes.com/fact-check/amazon-bankrupting- united-...](https://www.snopes.com/fact-check/amazon-bankrupting-united- states-postal-service/)</comment>


MCUBoot Bootloader for PineTime Smart Watch (NRF52) - <AUTHOR> https://lupyuen.github.io/pinetime-rust-mynewt/articles/mcuboot <comment><AUTHOR> Doing Wireless Firmware Updates the right way on PineTime Smart Watch... With the open source MCUBoot Bootloader from Apache Mynewt and Zephyr.

[https://lupyuen.github.io/pinetime-rust- mynewt/articles/mcub...](https://lupyuen.github.io/pinetime-rust- mynewt/articles/mcuboot)</comment>


Ask HN: How do you protect your IP in a startup? - <AUTHOR>

Hopefully, the co-founders have completely vetted a person when adding members to the startup team. References, coding tests, thorough interview, etc. But what happens when they actually need to start working? You are probably handing them keys to the entire kingdom because you need them in all corners of the product when it is still small.<p>While there is always the legal route, I am looking for more practical lessons learned by people who have already gone through this. Without impeding a new person's passion to jump right in and contribute immediately, how have you protected your code from being downloaded and walking away? <comment><USER2> IP has gone "the way of the dodo", meaning become obsolete, for all digital copyright forms including software. The solution is to develop a robust business model that depends on generatives. See [http://www.kk.org/thetechnium/archives/2008/01/better_than_f...](http://www.kk.org/thetechnium/archives/2008/01/better_than_fre.php).

Assume your competitors are already doing the same thing and even putting out better code. Your business model should be robust enough to withstand this also. Consequently, a new worker who downloads and walks away is no greater threat than the existing competitor, assumed or real. Stronger stated... the loss of IP and consequent spread of one of your infinite resources... why that's beneficial advertising in this day and age. Get the business model right, and the IP worry disappears.

Open source is like the musician giving away free mp3s. Proprietary code, and all the IP concerns it requires, are like overpriced physical CDs from major labels. More prosperity awaits you in the long tail and in generatives.

Best of luck!

</comment><comment><USER3> You probably can't. If the code is all you've got, someone else is probably going to beat you anyway, especially if you're spending a bunch of time worrying about it instead of building stuff.

Instead of paranoid maneuvering to protect something of unproven worth, spend your time creating an awesome place to work and a business culture that treats customers/users right and it won't matter all that much if someone steals some code or clones your software, there's far, far more to being successful than a few loc's.</comment>


William Gibson on writing, science fiction and the Future - <AUTHOR> http://blog.williamgibsonbooks.com/2010/05/31/book-expo-american-luncheon-talk/ <comment><USER2> I grew up reading Neuromancer and the Sprawl trilogy. I can honestly say that it largely influenced me into my current career (programmer).

I really wish that Gibson wasn't so bored with capital F Future. I would love to see what kind of hard-scifi novel he could produce today.

Everything he wrote seemed so terrible and magnificent at the same time and I strongly believed that it helped shape the direction of technological progress for a generation. You can't capture the hearts and minds of an entire generation of teen geeks and it not leave its mark.

<comment><USER3> I was interested to find out that he's not a singularity type (he's at pains to say this in a way that only singularity types will notice, though).

Many sci-fi authors today do subscribe to the idea of the singularity, and feel that it is impossible to do the sort of 'life in 50 years' Sci-Fi prognosticating that Gibson did in Neuromancer.

My favorite of the prognosticators is Vernor Vinge; I loved Rainbow's End for its balls-out attempt to paint a picture of (and make sense of) a near-ish future. Even that doesn't get 50 years out, though.

Taking a totally different spin (and one he takes in his essay): Neuromancer is a product of its time just like, say Echo and the Bunnymen, David Bowie, or the Cure. Seen in this light, you can complain about the lack of new quality music today, or just get with the program and learn to appreciate Lady Gaga.

Put that way, this first decade of the millenium is one which holds huge promise, huge unknown dangers, and a pervasive sense of lack-of-shock by we- the-people living in it. We should expect our Sci Fi literature to be variously engaging in this or responding to it.

This is what I've liked so much about his last two novels; the real (or realistic, or at least possible in today's society) brought out and examined as the bizarre. I'm really looking forward to the close of this trilogy in the fall.

<comment><USER4> > _just get with the program and learn to appreciate Lady Gaga._

I know it's a little off-topic, but I don't find Lady Gaga to be all that 'new.' She just reminds me of Cher.

[Further off-topic: Chromium's dictionary didn't think 'reminds' was a word]

<comment><USER5> That's because in the capital-F Future you cannot 're-mind'; you can only 'mind'.

</comment></comment></comment></comment><comment><USER6> Sounds like post-modernism, or [http://en.wikipedia.org/wiki/The_End_of_History_and_the_Last...](http://en.wikipedia.org/wiki/The_End_of_History_and_the_Last_Man)

I agree the future isn't what it used to be. I think it's that technology fundamentally changed our social structure, and while it was assimilating the technology, it created a gap, an unknown, that we could escape to, and which might answer perennial questions about being a human, for better or worse. But now we've assimilated it, so that gap is no more.

Perhaps we'll get science fiction again, when next we develop a technology that fundamentally changes the structure of society. Continuously improving communication wouldn't do it; that's one of the things we've assimilated. Don't know what it would be, but perhaps a way of looking for it would be to examine our social structures, and ask what changes it copes well with, and what it wouldn't. ie. hack society.

</comment><comment><USER7> I loved Gibson at the time, but it seems he doesn't really have the passion of a futurist, like my personal fave Greg Egan. I've always thought that writers who use SF merely as a trope to talk about the present sort of miss the whole point. Yes, the present is the launchpad; but what is interesting is to speculate about the possible futures any particular now might imply.

I have to assume PKD would find something to write about, were he alive today.

<comment><USER8> Yes, probably. PKD wrote paranoid fiction (his own words, I believe)--his stories are not really tied to an particular technology, but more to a state of mind.

</comment></comment><comment><USER9> I like his thought about the capital-F future only really being present in the minds of people of a certain age/cultural background, and the alternative being a kind of endless digital Now, but I don't know that I completely buy it.

The digital Now, as a concept seems as if it needs some kind of thinking comprehension as a state. An inward recognition that as he puts it "the future is always someone else's past". But I don't see that when I look around me. I don't see a society filled with people conscious of what's around them, I see one filled largely with sleepwalkers. Where ground-breaking technological marvels are not accepted as part of a capital-N Now, but simply ignored, or never apprehended. I don't know, but I fear that the end of the Futurist is more to do with the end of the Presentist - you can't consider the future without the springboard of the present, and current culture seems to be too numbing for most people to have the will, or need, to do so.

Well, that came out much more grumpy than I'd thought.

</comment><comment><AUTHOR> My fave quote from the article: _A book exists at the intersection of the author's subconscious and the reader's response_

<comment><USER3> This is fairly standard 'death of the author' literary theory, except, Gibson has a nice way with words. I guess I'd call it style. A really nice book about modernism meeting post-modernism in literary theory (written for nerds) is Richard S. Powers' book Galatea 2.0. You might like it.

</comment></comment><comment><USER10> Thing is, while Spook Country and Pattern Recognition are not groundbreaking the way Sprawl Trilogy was, Gibson still remains a truly gifted writer who has a way with words.

Too much of sci-fiction has been written by people with great ideas, but inferior way of writing them down.

</comment><comment><USER11> William Gibson - Still my favorite sci-fi author. Orson Scott Card a close 2nd.

<comment><USER12> _opens mouth and raises finger_

 _closes mouth and walks away_

</comment></comment><comment><USER13> "I called it Zero History because one of the characters has had a missing decade, during which he paid no taxes and had no credit cards. He meets a federal agent, who tells him that that combination indicates to her that he hasn't been up to much good, the past ten years. But that quotidian now finds him. Events find him, and he starts to acquire a history. And, one assumes, a credit rating, and the need to pay taxes."

Interesting. Will there be a free online version?</comment>


How to Create a Firefox Plugin (hacker-friendly javascript framework) - <AUTHOR> http://blog.popupchinese.com/?p=19

<comment><USER2> firefox plugins aren't really all that hard to begin with. i'm not sure if you're gaining much with this framework

<comment><USER3> firefox plugins are actually pretty tough to get started with if you are new to them, even for the adept hacker. there's just not that much in the way of introductory documentation out there. and sure all plugins are open source, but it isn't that fun to try and reverse engineer someone's plugin just to figure out how things work.

i really like the looks of this! thanks for posting.

<comment><USER4> Not to forget that some of the tutorials and examples floating through the Internet are outdated.

</comment></comment></comment><comment><USER5> just glancing over the instructions it already seemed harder to get working than jetpack(<https://jetpack.mozillalabs.com/>) and they seem to have the same goals

<comment><USER6> Jetpack is an additional extension install for users.

This framework looks like it builds native extensions without an extension needing to be preinstalled - at least until jetpack is shipped with ff.</comment></comment>


Old graph paper - <AUTHOR> http://leancrew.com/all-this/2015/08/old-graph-paper/ <comment><USER2> My favorite kind of graph paper is engineering paper. The grid is printed on the back, so when scanned it isn't visible.

What it looks like in person: [https://upload.wikimedia.org/wikipedia/commons/5/55/Engineer...](https://upload.wikimedia.org/wikipedia/commons/5/55/Engineering- pad-simulation.png)

What it looks like scanned: [http://3.bp.blogspot.com/_wP_s3WyQd4A/S-s4B-sm4oI/AAAAAAAAAe...](http://3.bp.blogspot.com/_wP_s3WyQd4A/S-s4B-sm4oI/AAAAAAAAAek/8qWpkCf2xnA/s1600/scan0009.jpg)

<comment><USER3> Is this how all engineering paper is (or pads)? Took a quick look on Amazon and only one had the same or similar pattern.

What's a good brand?

<comment><USER4> I have a few sheets of K&E from my grandfather's, they're fantastic. I'm thinking about framing one.

My go-to is Staedtler, simply because it's available. My dad still uses a lot of National. I've also used Ampad, which I find to be a little thin, and the fibers are course: tends to gouge.

<comment><USER5> I used to use the Staedtler, for that reason. Is very nice. But the Rhodia pads, as mentioned below, are exquisite.

<comment><USER4> I'm unclear. I use bound Leuchtturm1917 books for note taking these days, and I used to use moleskine. I have a number of others, including a Rhodia and white lines. I am not aware of Rhodia selling what I would call an engineer's pad. Graph paper, yes. Engineer's pad, no. Can you cite a link?

<comment><USER5> I apologize. I don't think I've seen an Engineer's Pad from Rhoda, for sure. I use one of the gridded variations.

</comment></comment></comment></comment></comment></comment><comment><USER6> All my notebooks are graph paper. I wanted to use them for composition but my teachers complained. I explained quite correctly that with graph paper you had lines for text and _bonus_ you could draw diagrams as well. How cool was that?

Apparently not cool enough, and one English teacher insisted on "wide rule" composition notebooks, it made me ill to write in it.

One of these days I'll buy enough Eureka Lab notebooks in a single order to have them customize them beyond the simple lab/engineering moniker. :-)

<comment><USER7> High school wasn't all fun, but one of the definite low points was breaking out one of your new notebooks and discovering that you accidentally bought a ten-pack of wide-rule notebooks.

I, uh, guess I was a nerd.

</comment></comment><comment><USER8> Another fun type of graph paper is composed of triangles in a hexagonal grid, commonly used for making isometric drawings:

[http://web.mit.edu/16.810/www/Isometric%20Drawing.pdf](http://web.mit.edu/16.810/www/Isometric%20Drawing.pdf)

For those of you looking to improve your by-hand visual communication skills, a cool old book is _Thinking with a Pencil_ . I picked up a copy a few months ago, and have been enjoying working through the exercises as I find time (which also includes isometric techniques):

[http://www.amazon.com/Thinking-Pencil-Henning- Nelms/dp/08981...](http://www.amazon.com/Thinking-Pencil-Henning- Nelms/dp/0898150523/)

</comment><comment><USER9> As far as the triangular grid goes, it's not common, but is very useful when you need it.

Ternary diagrams are probably the main use for it. They're particularly common in the geosciences as many classification schemes and solid-solution phase diagrams are defined in terms of a mixture of three components.

I used it through most of undergrad to make ternary diagrams by hand (and had to remember and draw in various classification schemes off the top of my head).

It's hard to find, so I would guess that professors are still handing out badly photocopied versions of an ancient sheet of triangular graph paper. (Sure it would be easy to create a nice blank ternplot with grids in $plotting_package_of_choice, but what's the fun in that??)

<comment><USER10> Its very much not hard to find triangular graph paper today. It may be hard to walk into a brick-and-mortar retail store and find it (though I wouldn't be surprised if _campus_ bookstores in places where it was used in courses carried it), but its quite easy to find online, both printable and pre- printed.

So there's really no real reason anyone should be relying on "badly photocopied versions of an ancient sheet of triangular graph paper" (that's not saying that there aren't people doing it, just that there's no good reason for them to be doing it.)

<comment><USER9> Good point. I'm sure I could order it from Amazon/whatever and have it here day-after-tomorrow.

My memory of "very hard to find" meant that 15 years ago the campus bookstore didn't carry it.

I'd still bet that badly-photocopied sheets of ternpaper are being handed out on a daily basis in Petrology classrooms around the globe, though :)

<comment><USER11> If you can see through the ads, this site has what you want:

[http://incompetech.com/graphpaper/trianglehex.html](http://incompetech.com/graphpaper/trianglehex.html)

Adjust line parameters as you like, and it gives you a PDF.

I used it to get a hex grid when explaining Pascal's triangle to my kid.

</comment></comment></comment></comment><comment><USER12> I count 10 graph paper notebooks at arms length as I type this. I use the wonderful Japanese Maruman Mnemosyne notebooks and a fountain pen. People think I'm nuts, maybe I am but the combination brings me great joy.

[http://www.jetpens.com/Maruman-Mnemosyne-Inspiration- Noteboo...](http://www.jetpens.com/Maruman-Mnemosyne-Inspiration- Notebook-A5-5.8-X-8.3-5-mm-X-5-mm-Graph-70-Sheets/pd/4078)

<comment><USER13> Looks nice.

I'm currently working my way through a Whitelines spiral bound graph paper notebook that I'm pretty pleased with.

</comment></comment><comment><USER14> This was the paper I loved for drawing Dungeons and Dragons maps in the late 70s. I loved how a #2 pencil looked on the faded blue grid. The paper has a distinctive smell, it's just delicious.

<comment><USER15> This was my thought - the main use for me was D&D!

</comment></comment><comment><USER16> I was a fan of analytic geometry back in high school. It illuminates so many mathematical and physical facts and propositions. It also enables you to take a brute force approach to solving seemingly impossible problems - just graph the thing and see where the curves intersect.

Then at some point I discovered computers and realized the true magnitude and capabilities of numerical methods.

Anyway, plotting graphs, that will always be fun.

</comment><comment><USER17> ICYI: Downloadable Graph Papers [http://www.printablepaper.net/](http://www.printablepaper.net/)

<comment><USER18> Impressively they even have Smith charts, for a graphical representation of RF transmission lines.

For a closely related good time hit images.google.com and try nomogram and nomograph for various paper and pencil based calculators.

I spent many an hour wargaming on hex grids in the olden days.

(edited to add: Oh my. I suppose its inevitable people would print on demand hex notebooks: [http://www.lulu.com/shop/jed-mcclure/albatross-dungeon- noteb...](http://www.lulu.com/shop/jed-mcclure/albatross-dungeon- notebook-008/paperback/product-20420848.html) )

<comment><USER17> Nomogram's remind me of slide rulers!

</comment></comment></comment><comment><USER19> Graph paper is still commonly required for math class in Israel (at least in elementary school). (E.g., supplies list for 2015-16 school year (word doc) [http://www.yigalalon.org.il/uploadfiles/igalalon/%D7%A8%D7%A...](http://www.yigalalon.org.il/uploadfiles/igalalon/%D7%A8%D7%A9%D7%99%D7%9E%D7%AA%20%D7%A6%D7%99%D7%95%D7%93%20%D7%AA%D7%A9%D7%A2%D7%95.doc)).

<comment><USER20> Please include [http://](http://) when you post URLs.

Or start very long lines with four spaces.

<comment><USER19> Apologies, corrected.

</comment></comment></comment><comment><USER21> I recall using a lin-log and log-log graph paper when I was 16 or so.

I suspect we HAD to use them because the school had some leftovers. We drew graphs on them for like 20 mins and then did it on the computer (GeoGebra I think).

</comment><comment><USER22> I have log paper and lab notebooks stashed away in case of armageddon or something. I like paper still, a lot.

</comment><comment><USER23> "Specialty graph paper" \- wow... I had never suspected there was anything but the square grid - and I'm old enough to have used it in my teenage years !

<comment><USER24> I learned to write on Seyès grid paper (exactly like this: [https://wonderpens.wordpress.com/2015/04/03/how-to-use- seyes...](https://wonderpens.wordpress.com/2015/04/03/how-to-use-seyes-or- french-ruling-for-handwriting/)).

There's a lot more than square grid. Though all my note books are 5x5mm grid papers these days (and usually square: [http://rhodiapads.com/collections_orange_le_carre.php](http://rhodiapads.com/collections_orange_le_carre.php))

<comment><USER25> Ugh, yeah, that's what they have here in France. Gives me a headache to look at my writing being criss-crossed by the overly heavy ruling :/

Perhaps i should sometime become un-lazy and look for some proper paper, rediscover the joy of writing :)

My other gripe is that my fountain pen keeps drying up (i use it too infrequently) and as a result i'm reduced to using those horrible throw-away BICs, at least they don't dry up. Does anyone have any golden tips for keeping fountain pens healthy?

</comment></comment></comment><comment><USER26> Am I dating myself to say that at my right hand is a pad of graph paper? I take my notes on it; it's wonderful to have both horizontal and vertical guides.

<comment><USER27> Maybe. I used them through college some 20 years ago prefered the same for years afterwards but have switched to yellow legal pads for temp scratch surface and [https://workflowy.com/](https://workflowy.com/) for note taking. Not sure why, but I like the yellow.

</comment></comment><comment><USER28> I have some old lab notebooks of my dad's from the 1950s. Also the india ink pens and lettering stencils he used to label figures in his thesis and other papers. All very high quality stuff and must have been pretty significant purchases for a grad student in those days.

</comment><comment><USER29> I found various types of old graph paper in my father's desk when I cleaned it out. I've kept most of it. He's an EE and a ham radio operator, so he had lots of things to graph.

</comment><comment><USER30> When I was a kid, my sister and I drew "pixel art" on graph paper. I bet we would have had a lot of fun with the isometric grid.

</comment><comment><USER31> I have a lot of this stuff from my dad, from the early 60s. Mostly various types of log paper, and polar.

</comment><comment><USER32> Anyone notice their handwriting speed and clarity goes up when writing on graph paper?

</comment><comment><USER33> duckduck the phrase "generate graph paper" \-- there are many sites offering a wide range of PDFs generated to your specs.</comment>


Farming Now Worse for Climate Than Deforestation - <AUTHOR> http://www.climatecentral.org/news/farming-now-worse-for-climate-than-deforestation-18629

<comment><USER2> "The research shows that the recent climate-protecting gains in forests are being nearly canceled out by efforts to satisfy the world's growing appetite — particularly its appetite for meat."

This. We're basically just pissing away most of the crops for some luxury food items while many people starve while bringing about global warming. Efficient resource allocation at its finest!</comment>


The shortest paper ever published in a serious math journal explained - <AUTHOR> http://fermatslibrary.com/s/shortest-paper-ever-published-in-a-serious-math-journal-john-conway-alexander-soifer <comment><USER2> This is really interesting, the full story is told here:

[http://www.wfnmc.org/mc20101.pdf](http://www.wfnmc.org/mc20101.pdf)

During the years 2002–2004 I was visiting Princeton University with its fabulous mathematics department, a great fixture of which was a daily 3 to 4 PM coffee hour in the commons room, attended by everyone, from students to the Beautiful Mind (John F. Nash Jr.). For one such coffee hour, in February 2004, I came thinking—for the hundredth time in my life—about the network of evenly spaced parallel lines cutting a triangle into small congruent triangles. This time I dealt with equilateral triangles, and the crux of the matter was a demonstration that n2 unit triangles can cover a triangle of side n. I asked myself a question where the continuous clashes with the discrete: what if we were to enlarge the side length of the large triangle from n to n+ε, how many unit triangles will we need to cover it? This comprised a new open problem: Cover-Up Problem 1. Find the minimum number of unit equilateral triangles required to cover an equilateral triangle of side n + ε. During the next coffee hour, I posed the problem to a few Princeton colleagues. The problem immediately excited John H. Conway, the John von Neumann Professor of Mathematics. From the commons room he went to the airport, to fly to a conference. On board the airplane, John found a way (Figure 1) to do the job with just n2+2 unit triangles! (Area considerations alone show the need for at least n2 + 1 of them.) Conway shared his cover-up with me upon his return—at a coffee hour, of course. Now it was my turn to travel to a conference, and have quality time on 28 Mathematics Competitions Vol 23 No 1 2010 an airplane. What I found (Figure 2) was a totally different cover-up with the same number, n2 + 2 unit triangles! Upon my return, at a coffee hour, I shared my cover-up with John Conway. We decided to publish our results together. John suggested setting a new world record in the number of words in a paper, and submitting it to the American Mathematical Monthly. On April 28, 2004, at 11:50 AM (computers record the exact time!), I submitted our paper that included just two words, "n2 + 2 can" and our two drawings. I am compelled to reproduce our submission here in its entirety.

<comment><USER3> I read the story. So much for publishers not doing at least 80% of the work when it comes to publishing papers.

</comment></comment><comment><USER4> Another example of a short peer-reviewed paper (and related to Computer Science, yay!) is "Counterexample to Euler's conjecture on sums of like powers": [http://fermatslibrary.com/s/counterexample-to-eulers- conject...](http://fermatslibrary.com/s/counterexample-to-eulers-conjecture- on-sums-of-like-powers)

<comment><AUTHOR> Hi Marat_Dukhan! By the way that paper has also been annotated on Fermat's Library: [http://fermatslibrary.com/s/counterexample-to-eulers- conject...](http://fermatslibrary.com/s/counterexample-to-eulers-conjecture- on-sums-of-like-powers) :)

<comment><USER4> Thanks! I updated the link

</comment></comment></comment><comment><USER5> Wasn't there a single page PhD thesis that was a single sentence describing a counter-example for some long-standing conjecture?

I realize it's vague (to put it mildly), but it was 20-something years since it came up in the math class in the Uni.

 _Edit_ \- Haha, found it! It was in Littlewood's Miscellany - Picard's Theorem [1].

[1] [https://books.google.ch/books?id=MjVgeT7Laf8C&pg=PA40&lpg=PA...](https://books.google.ch/books?id=MjVgeT7Laf8C&pg=PA40&lpg=PA40&dq=An+integral+function+never+0+or+1+is+a+constant&source=bl&ots=ov_dqTGKL1&sig=4yqDoeXwS_JKjcb8NqdpnHqQI-o&hl=en&sa=X&ved=0ahUKEwjv7Y66iarJAhXJaRQKHS-2AN0Q6AEIGzAA#v=onepage&f=false)

</comment><comment><USER6> I'm personally a fan of John Nash's paper, "Equilibrium Points in n-Person Games" [1]. It's the bottom of page 48 and the top of page 49. It's quite high on the impact to word count ratio.

My understanding (which I haven't verified) is that this is the main paper resulting in his Nobel prize.

[1] [http://web.mit.edu/linguistics/events/iap07/Nash- Eqm.pdf](http://web.mit.edu/linguistics/events/iap07/Nash-Eqm.pdf)

</comment><comment><USER7> Is there a way to get rid of the 'Sign up with Facebook/Google' overlay that blocks the bottom part of the comments?

<comment><USER8> There's a very clear hide link to click, there's no need to open Dev tools like the other comments are suggesting.

<comment><USER7> You may be the Chosen One. I don't see a hide link on the overlay that obscures comments.

</comment></comment></comment><comment><USER9> One of the authors, John Conway, is the inventor of the Game of Life: [https://en.wikipedia.org/wiki/John_Horton_Conway](https://en.wikipedia.org/wiki/John_Horton_Conway).

<comment><USER10> If you like GOL, check out 'golly', the game-of-life simulator. It has tons of amazing examples included, including a cpu emulator. On sourceforge and probably in your favourite OS repos, too.

The banner on their homepage is a [low res version of a] valid game-of-life set: [http://golly.sourceforge.net/](http://golly.sourceforge.net/)

</comment></comment><comment><USER11> Is there an answer to the question? Is an n^2 + 1 tiling possible? Is there a proof that it is not?

<comment><USER12> It looks like proving that n^2 + 1 is impossible is still an open problem: [http://www.wfnmc.org/mc20101.pdf](http://www.wfnmc.org/mc20101.pdf).

</comment></comment><comment><USER13> what is this? I really don't understand how figure 2 has to do with figure 1, what the question is or what the construction is of the narrative I'm supposed to follow...

<comment><USER14> The comments on the left explain it (I didn't understand it either). Basically, it's known that an equilateral triangle of side length n needs n^2 unit triangles to perfectly tile it (e.g. you need 16 unit triangles to tile an equilateral triangle of side length 4).

Now, if you make the side length of the large triangle just a teeny bit longer (that's what epsilon is), what is the minimum number of unit length triangles it takes to cover the larger triangle? The two different figures show two ways this can be done with n^2 + 2 triangles: the first figure essentially adds 2 triangles to the base row (the comments show how they overlap a little bit), while the second figure uses 3 overlapping triangles to make up the "tip", instead of just 1 (again, the comments show how this works because the base row doesn't need any additional triangles).

Thus, these two examples show how it can be done with n^2 + 2 triangles. It's still an open question if it can be done with n^2 + 1.

<comment><USER15> _(the comments show how they overlap a little bit)_

OH. Thank you. This is what I was missing; I understood "cover" to mean "tile" and thought the bottom row was just misprinted slightly.

</comment></comment></comment><comment><USER16> This website is the TeX/Web combination I ever dreamt of!

</comment><comment><USER17> Asher Peres has a pretty famous short paper in quantum information: [http://arxiv.org/abs/quant-ph/0310035](http://arxiv.org/abs/quant-ph/0310035)

</comment><comment><USER18> Unrelated to the published paper. Fermatslibrary is fascinating. Is there something similar for CS papers? I would love this for some distributed systems papers.

<comment><USER19> Here's something similar for CompSci: [http://paperswelove.org/](http://paperswelove.org/)

They had a presentatino on the Paxos paper about a month ago: [http://www.meetup.com/Papers-We-Love- London/events/225736762...](http://www.meetup.com/Papers-We-Love- London/events/225736762/)

</comment></comment><comment><USER20> Some shorter proofs are available in the book "Proofs without Words."

But then again, that book begins with a description that visual arguments aren't truly proofs.

<comment><USER21> As one of my favorite math professors once pointed out, a proof is merely an argument that convinces people, so whatever works works.

<comment><USER22> Before the advent of computers we had two notions of proof in mathematics, the French school and the Russian school.

The Russian school is basically `something that convinces humans'. The French school is all about formality.

Since computer became a thing, the field has blossomed. Look at zero knowledge proofs and various forms of interactive proof systems as examples.

<comment><USER21> But the formality is, at bottom, just a set of rules for convincing somebody.

<comment><USER22> Some people would say that the formal proof stands on its own. No need for anyone to appreciate it.

</comment></comment></comment></comment></comment><comment><USER23> This simultaneously proves that there is a lower bound on the number of words in an academic paper. :)

</comment><comment><USER24> Another short paper published in the American Mathematical Monthly by Doron Zeilberger can be found here: [http://i.imgur.com/PSigYcb.png](http://i.imgur.com/PSigYcb.png)

</comment><comment><USER25> It would have benefited from being a little longer. It takes about as long to figure out that they leave open the question whether n^2+1 can, as it would to come up with the same or similar constructions on your own!

</comment><comment><USER26> I count 14 words (11 in the title, 1 in the body + 2 times "figure"), not 2. And 14 more if you count the authors names and affiliation as words.

<comment><USER27> The statement about the two words only concerns the body, and the formula _n_ ² + 2 counts for one word.

<comment><USER28> Why would you count a compound expression, with internal spaces, as one word?

<comment><USER29> Technically "n^2+1" has no spaces.

And I guess one way to think about it is that terms in an expression can be viewed as letters, so the expression then becomes a word.

<comment><USER30> How do you pronounce that word?

<comment><USER29> "n squared plus one"</comment></comment></comment></comment></comment></comment>


TechCrunch: The Age of Startups Is Over - <AUTHOR> https://techcrunch.com/2017/10/22/ask-not-for-whom-the-deadpool-tolls/ <comment><USER2> This industry is cyclical. It'll come around again.</comment>


Yahoo Announces Public Disclosure of National Security Letters - <AUTHOR> https://yahoopolicy.tumblr.com/post/145258843473/yahoo-announces-public-disclosure-of-national <comment><USER2> Does anyone else find it odd that these letters are not signed by a judge and are signed by the 'Special Agent in Charge?'

<comment><USER3> It would be odd if an NSL was signed by a judge, since NSLs are administrative directives that do not need to be approved in advance by a judge (they, and any associated non-disclosure order, can be challenged in court _after_ issued.)

<comment><USER2> Gotcha. Thanks for the clarification.</comment></comment></comment>


Reverse engineering a router part 1 – Hunting for hardware debug ports - ernesto-jimenez http://jcjc-dev.com/2016/04/08/reversing-huawei-router-1-find-uart/ <comment><AUTHOR> Cool, looking forward to the next post.</comment>


Cryptocurrency Market Plumbs New Depths in 2018 - <AUTHOR> https://www.wsj.com/articles/cryptocurrency-market-plumbs-new-depths-in-2018-1534241274 <comment><USER2> Anyone want to post the article?

Here are my 2 reasons

>Bitcoin is surviving because its a useful application of blockchain. It was designed to be limited in supply, so people could store value without relying on a government currency, government land rights, or nuclear chemistry obsoleting gold.

>Alt coins are collapsing because dApps are unused due to the extremely high cost and unpredictable times of blockchain. There is no usecase.

I think people fell for the youtube videos saying Blockchain was going to make web 3.0 without realizing you wouldnt pay 7 notaries to verify your July 4th photos for social media.

<comment><AUTHOR> [https://outline.com/SpCPNW](https://outline.com/SpCPNW)</comment></comment>


The "Girth-Wealth" Gradient: the poorer you are the fatter you're likely to be - <AUTHOR> http://www.slate.com/id/2229523/pagenum/all/

<comment><USER2> They don't need to do anything to solve the fat people problem. Just remove all crop subsidies and the problem will eventually solve itself. It's more expensive to eat healthy because the crops used in making unhealthy foods are heavily subsidized. At my local Kroger two red bell peppers cost more than a twelve pack of generic soda. A sprig of cilantro costs $.75 inside, but a soda can be bought from a vending machine in the front for $.50.

<comment><USER3> Is that hypothesis backed up by any data?

Australia and New Zealand have (almost) no agricultural subsidies, and yet have the sixth and seventh highest obesity rates in the world.

<comment><USER4> Do they import cheap food from abroad?

<comment><USER3> Australia hardly imports any food at all, because it's large and climatically diverse enough to support just about every crop in the world.

And yet people are still fat. Y'know why? Because they eat too much. Do they eat too much because they're too poor to afford better food? Nope, they eat too much because food is tasty and they have imperfect self-control.

</comment></comment></comment></comment><comment><USER5> Link is just a Times landing page; here's the real article: <http://www.slate.com/id/2229523/pagenum/all/>

</comment><comment><USER6> This is a well known problem. Healthy food is just too f-ing expensive.

If anyone is looking for a billion dollar idea, try making a healthy tasty affordable fast food chain. And no subway does not count, it tastes like cardboard.

The biggest problem with the healthy fast food chain is supply of fresh produce. One of the main reasons bad food is so much cheaper is simply because it lasts longer and thus can handle the long nationwide supply chains that are currently prevalent.

But that is the exact type of problem that should be solvable with present technology. You could connect all the small farmers in an area in some kind of online market and allow them to sell produce directly to restaurants at weekly or daily auctions or even sell contracts for future delivery of produce. Thus, the restaurants can have a way to get their supplies cheaply and reliably and directly from the farmer.

<comment><USER3> Where do people keep getting this idea that healthy food is expensive? Do they live in areas substantially different from mine? At my local supermarket most fruits and vegetables cost between $1 and $2.50 a pound. A whole head of lettuce is, like, a buck. Rice costs almost nothing. A potato costs... I dunno, but it's not much.

<comment><USER7> _Do they live in areas substantially different from mine?_

Probably. The article is talking about how poor people are fat. At grocery stores in poor neighborhoods, healthy stuff is significantly more expensive, or simply does not exist. For instance, a can of black beans at the ghetto grocery store by my apartment near Bushwick costs twice as much as it does at the Whole Foods in Union Square. Produce is rarely available, and when it is, it's almost spoiled.

<comment><USER3> For what it's worth, the "local supermarket" I was talking about is on the border of Oakland, and the area is so ghetto that they keep not only the liquor and razor blades, but also the toothbrushes and condoms, in locked cabinets.

I see plenty of fat people there.

<comment><USER7> Which supermarket is it? I used to live on the Oakland border.

<comment><USER3> The Pak N Save in Emeryville.

</comment></comment></comment></comment></comment></comment><comment><USER3> I hate these articles which pop up every week or so, trying desperately to make the claim that fat poor people are the victims of anything other than their own lack of self-control.

We all have to make decisions in life. Do we go to school, or do we cut class? Do we work hard, or do we slack off? Do we eat that cheeseburger, or do we have the salad? Do we go to the gym, or do we sit around eating chocolate ice cream in front of the TV?

Some people are better at making these decisions (i.e. choosing the less immediately satisfying option for long term gain) and some people are worse. It should not be surprising that the people who are bad at making these decisions tend to wind up both fat and poor.

</comment><comment><USER8> I know this is far less politically correct than discussing subsidies and prices, but can it be that poorer communities just assign less value to eating well and staying healthy and are not necessarily looking to maximize nutrition per dollar?

<comment><USER9> Could be. Looking at it economically, let's say I have a farm that produces equal amounts of two food items. They're fairly indistinguishable, but one is healthier, say because it has lots more omega-3 oils.

Which one would I charge a premium for? Which one would I make most of my money on? Which one would end up with the fancier packaging? Remember, that's presuming it's no more expensive to produce the healthy stuff.

And who would pay that premium? Who would eat the less-healthy stuff? Taking those two kinds of consumers as the model, I think that's why anywhere a business can apply price discrimination to a healthier food, it totally will.

<comment><USER8> I don't know which one you'd pay a premium for. You'd see which one you're selling more of and charge a premium for that.

The reality is, foods aren't indistinguishable. They have different tastes, different marketing, different cultural value, etc. How "good" something is is not, and never was, a prime indicator of success in the marketplace or value to the consumer. If Pepsi wants to spend billions on advertising, people will buy Pepsi.

I'd also venture a guess in saying that you don't just get a tally of every food component available within some distance of your house, their nutritional content and their price, and then you just optimize on nutrition regardless of what your favorite childhood dish was, or what you're in the mood for or what your friends are having.

All I'm saying is it isn't that simple as turning into a simplified problem of supply and demand. Go to a fried foods place at a poor neighborhood and watch how people order; I sincerely doubt they'd always end up getting the cheapest thing just that's what they can afford. Certain lifestyle choices lead you to a certain lifestyle (or perpetuate it) and completely forgetting those choices for problems like obesity is being disingenuous with yourself.

<comment><USER9> It's not as simple as you say either, so I don't know what I'm supposed to say here. But thanks for the conversation.

</comment></comment></comment></comment><comment><USER10> Who says healthy food is more expensive? For $20 I can get enough bananas, oatmeal, tuna, eggs, and cucumbers to last me a week (easily). What's expensive is the great tasting healthy stuff - lean chicken breasts, sushi, good cuts of steak, exotic fruits and vegetables, etc. And this is a rude thing to say, but there's a lot of fat people who given a little more money would prefer an extra big mac and mcFlurry with their combo rather than wild rice and BBQ'd salmon.

</comment><comment><USER11> Though I hate social engineering taxes, the easy way to fix the regressive nature of the fat tax would be to cut a cheque to every person legally living in the country. While the poor now have to pay, say, $1000 more per year they are also cut a cheque worth $1100, giving them real choice between healthy and nonheathly.

<comment><USER12> Nah, that's not how it works. I rarely go to supermarkets any more but when I do I always see the same thing: fat mothers, fat kids, trolley full of processed food and then to the cigarette kiosk to load up on fags, gossip and TV magazines, and lottery tickets. You can feed a family of four healthy food bought from the market for a day for the cost of 20 smokes - Indian and Italian food in particular is incredibly cheap to make from scratch. The problem is _not_ one of affordability. Anyone who says it is has a political agenda.

<comment><USER13> Kind of. Having lived for the past two years now on the low end of the income spectrum, eating well is definitely more expensive than eating for the least possible. White bread is cheaper than Whole Wheat. Low fat meats are always more expensive than the fattier meats.

Mind you, either way it is cheaper or it breaks even at worst when compared to buying pre-processed foods, but the point is: you can save some money by eating a little worse.

<comment><USER12> It depends on how much prep you're prepared to do. You can make a hearty lentil curry very cheaply, for example, if you buy the basic ingredients in bulk. 'Course this presupposes that you know how to cook, but that knowledge is very nearly free, the only investment is in time.

<comment><USER14> Wasn't it pointed out in a previous article linked here on HN that the poor tend to have less free time?

<comment><USER3> Some poor people have too little free time (the ones working two minimum-wage jobs) while others have too much (the unemployed). It would be interesting to compare the obesity rates of the two groups. I doubt you'd find that the unemployed were thinner.</comment></comment></comment></comment></comment></comment>


Show HN: CiiMS 2 Beta - A High Performance CMS Built in Yii - <AUTHOR> https://github.com/charlesportwoodii/ciims

<comment><AUTHOR> A detailed writeup of everything that is included in this release can be found at [https://www.erianna.com/ciims-2-0-0-beta-release- announcemen...](https://www.erianna.com/ciims-2-0-0-beta-release- announcement).</comment>


This is definitely the best designer's portfolio - <AUTHOR> http://www.balgova.com

<comment><USER2> [NSFW] - Maybe people should put that in the title when they post NSFW links?</comment>


Apple source code for OS X 10.11 - <AUTHOR> http://www.opensource.apple.com/release/os-x-1011/ <comment><USER2> It is the Core of OSX named Darwin. There used to be ISO files to burn to DVD and install it, but now we just get the source code. [http://apple.stackexchange.com/questions/72095/where-can- i-f...](http://apple.stackexchange.com/questions/72095/where-can-i-find-the- latest-release-of-darwin)</comment>


Microsoft's new tool helps developers assess the attack surface of applications  - <AUTHOR> http://www.securityweek.com/microsoft-releases-attack-surface-analyzer-encourage-secure-software-development

<comment><USER2> This is good. Use it! I've been using this for a few years and it helps find a lot of various security issues. It's been especially useful in the appliance world.</comment>


How Hashing Could Stop Violent Videos From Spreading - <AUTHOR> https://www.cnn.com/2019/03/15/tech/new-zealand-video-viral-social-media/index.html <comment><USER2> It's far too easy to subtly edit a video so that the hashes of the key-frames won't match. This would work for flagging unedited videos, but people could defeat it pretty quickly.

</comment><comment><USER3> I think if YouTube could catch duplicate videos with a simple "hash" they would. Nice try, CNN.</comment>


Analysis: Is Siri's Competition a Real Threat for Apple? - <AUTHOR> http://techpp.com/2012/08/13/analysis-siri-competition-real-threat-for-apple/

<comment><USER2> 'Google Now' pawns Siri. I really hope Apple opens up Siri's API before it is too late. Remember, Google has 14 years of data and Apple needs to beat Google in terms of implementation alone.

</comment><comment><USER3> Have tried Iris for myself - it's not something that would be worth even installing. Sometimes I envy Apple for Siri but hopefully, something good will reach Android in the upcoming period.

<comment><USER2> Iris? That's not even worth comparing :|

</comment></comment><comment><AUTHOR> Monolith info right there!</comment>