No, negative masses have not revolutionized cosmology - <AUTHOR> http://backreaction.blogspot.com/2018/12/no-negative-masses-have-not.html <comment><USER2> I'm not a physicist, just an interested bystander but some of these arguments don't seem to hold water to me:

> There's a more general point to be made here. The primary reason that we use > dark matter and dark energy to explain cosmological observations is that > they are simple.

> A creation term is basically a magic fix by which you can explain everything > and anything.

Dark matter is an unknown 'substance' that interacts only through gravity (weakly) and must have a very specific and complex distribution in the universe to 'work'. That strikes me as neither 'simple' nor much different than tossing a constant into an equation to make it work. Similarly Dark Energy is an unknown form of energy that in uniformly distributed through the universe, which to me is just a fancy way of saying "we added a constant to make it work". In both cases I don't see how either are implicitly better than adding a 'creation term'.

<comment><USER3> I believe the author's argument is: however simple or complicated dark matter and energy are, negative (inertial) mass just makes things even more complicated, without offering any new (testable) insights. The author herself points out that she (and the GR community) may be wrong about a lot of this stuff (e.g. that gravity is mediated by a spin-2 field), but absent a testable hypothesis, negative masses don't actually move the field forward at all.

Seemingly "crazy" ideas sometimes turn out to be correct! But in science, we demand radical ideas at least make testable hypotheses.

<comment><USER4> > "it's highly problematic to introduce negative inertial masses because this > means the vacuum becomes unstable. If you do this, you can produce particle > pairs from a net energy of zero in infinitely large amounts. This fits badly > with our observations."

Basically, if you mess the the equation, you have to be very sure you aren't simulating something silly. Which is easy to do, unfortunately I've done it often.

I still need to read the original paper in detail to confirm, but if the post is correct, the N-body simulation might have some issues.

<comment><USER5> Waaait a minute, isn't that describing something we've already observed - spontaneous creation of virtual particle pairs in a vacuum?

<comment><USER6> We have definitely not observed spontaneous creation of virtual pairs in a vacuum. I do not blame you for thinking so as it is often described this way.

Almost no computation in Quantum Field Theory can be done exactly. What physicists do is using perturbation theory which is very similar to doing Taylor series in introductory calculus. Feynman, in a genius inspiration, found a way to represent the various mathematical terms that occur in these types of calculations as pictures which could be described in words. In this pictorial language, one would say things like "this term correspond to the creation of a virtual pair of particles", etc." The perturbation expansion is a mathematical "trick" done so that we can do obtain approximate results. Each individual term in that expansion has no physical meaning - in spite of the pictorial language used.

</comment></comment></comment></comment></comment><comment><AUTHOR> This is a critical response to [https://news.ycombinator.com/item?id=18609375](https://news.ycombinator.com/item?id=18609375) ; in the comments is a response by Jamie Farnes, the author of the paper, and a rebuttal by the blog's author.

<comment><USER7> I have absolutely no idea who is right, but I don't see why Dr. Hossenfelder is being so patronizing? In her rebuttal in the comments she says

>Trust me, I do not enjoy doing this, but I do not want false claims to spread in the popular science literature.

The only way to stop popular science lit from misinterpreting/aggrandizing scientific findings and publishing what eventually amounts to false claims would be to just never publish anything provocative at all...and then they'd still probably find some BS to publish. I don't really see why such reasoning would prompt this response for the paper.

<comment><USER8> > I don't see why Dr. Hossenfelder is being so patronizing

This is her personality. I don't think it's productive to resolving scientific disagreements and don't endorse it; she looks obnoxious in contrast to the author's polite reply in the comments. But it's definitely her natural state, and it seems to produce a writing style that readers enjoy.

> The only way to stop popular science lit from misinterpreting/aggrandizing > scientific findings and publishing what eventually amounts to false claims > would be to just never publish anything provocative at all

Hossenfelder is claiming much more than that the work is provocative. She's claiming it's highly disfavored for widely known reasons that the authors do not sufficiently address. She's probably also implicitly suggesting the authors are allowing their work to be marketed directly to the lay public, who do not have the expertise to assess the work, for personal gain. Obviously you can always give alternative explanations (the establishment is close-minded, or whatever), but keep in mind that Hossenfelder is waaaay outside the establishment.

</comment></comment></comment><comment><USER9> "[T]he gravitational interaction is exchanged by a spin-2 field, whereas the electromagnetic force is exchanged by a spin-1 field. Note that for this to be the case, you do not need to speak about the messenger particle that is associated with the force if you quantize it (gravitons or photons). It's simply a statement about the type of interaction, not about the quantization. Again, you don't get to choose this behavior. Once you work with General Relativity, you are stuck with the spin-2 field and you conclude: like charges attract and unlike charges repel."

There was a bit of discussion about this on [https://news.ycombinator.com/item?id=18609375](https://news.ycombinator.com/item?id=18609375) as well. Working through the exercise of how spin-2 mediated forces differ from spin-1 is a worthwhile exercise for those who are so inclined.

<comment><USER10> If negative mass experiences an attractive force (that is, one that adds momentum toward the source of the force), doesn't that push it away? After all, with negative mass, the momentum vector and the velocity vector point in opposite directions.

</comment></comment><comment><USER11> Occam's razor is a heuristic used in the investigative process, not a principle. While it's fair to point out that a theory makes everything more complicated and thus might make it less likely to be sound, it's not fair to push back on the first bit of research into a theory because they haven't had the time to fully develop it.

Indeed, a scientific revolution generally starts by treating as false an assumption previously held as true. Not to say that this is a revolution, but if you push back too hard it won't be, whether it's true or not.

<comment><USER12> History : Dun Scotus (really) probably invented Ockham's razor - William was his student and used it to avoid the thing that all medieval philosophers needed to avoid, namely being tied up and put on a bonfire.

Why did Dun invent it (probably)… well here's the thing, Christianity has a God with three faces, son, father and holy ghost thing. Why? The answer is - don't multiply entities beyond necessity, so God has the number of faces necessary to do the job, no more, no less.

I'm wittering on because this is where that heuristic came from, literally it's angels on pins stuff. So don't invest in it, I'd bet a bit that if we got Dun and Bill together with a few pints of mead they'd laugh themselves silly to here that 21st Century physics pins any weight onto their measure.

The Greeks wouldn't have, the Chinese didn't, why do we?

<comment><USER13> I mean, we still _call_ it Occam's razor, but I don't think that it's really even the same principle by this point, it just shares the same name. In science today, we don't really care about the number of entities. We don't reject the idea that the stars are suns like our own just because that would imply that the number of atoms in the universe is drastically larger than the number of atoms in the solar system. Instead of hypotheses with the least number of entities, we favour hypotheses with the smallest Kolmogorov complexity. [1] As a slogan for the modern version, I like the phrasing by John Von-Neumann: "With four parameters I can fit an elephant, and with five I can make him wiggle his trunk." [2]

[1] [https://en.wikipedia.org/wiki/Kolmogorov_complexity](https://en.wikipedia.org/wiki/Kolmogorov_complexity) [2] [https://www.johndcook.com/blog/2011/06/21/how-to-fit-an- elep...](https://www.johndcook.com/blog/2011/06/21/how-to-fit-an-elephant/)

<comment><USER14> Nitpick: The historical problem with stars being suns wasn't (just) the universe being larger than the solar system, but that the telescopic observations available at the time seemed to imply that every other visible star would have to be much larger than the Sun, in fact larger than the _orbit_ of Saturn. This was because early astronomers didn't understand optical diffraction and thought the Airy disks visible around stars were the stars themselves, making their angular radius in Earth's sky seem vastly larger than the reality. [1] Both characterization of the Airy disk and observation of stellar parallax didn't occur until the 19th century, by which point religious objections wouldn't have had the same status as in Galileo's day anyway (for example, Darwin's work was published only a few decades later).

Source: [http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.612...](http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.612.5617&rep=rep1&type=pdf)

</comment></comment></comment></comment><comment><USER15> Can't help but think of phlogiston:

 _Eventually, quantitative experiments revealed problems, including the fact that some metals gained mass when they burned, even though they were supposed to have lost phlogiston. Some[who?] phlogiston proponents explained this by concluding that phlogiston had negative weight;_

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

Eventually, the mass paradox was resolved by the realization that combustion is really something else altogether: the combination with a then-unknown element, oxygen:

 _Phlogiston remained the dominant theory until the 1770s when Antoine-Laurent de Lavoisier showed that combustion requires a gas that has mass (specifically, oxygen) and could be measured by means of weighing closed vessels._

<comment><USER16> Side note: it's pretty incredible how phlogiston theory correctly linked burning and rusting, despite being unaware of oxidation. (Also, that plants have a part to play in the oxidation-carbon cycle.)

I don't know if oxygen theory would have developed without phlogiston theory first linking these phenomena.

<comment><USER17> Almost certainly. Joseph Priestly, the discoverer of oxygen, was a confirmed phlogistonist. He even called oxygen "de-phlogisticated air". The reason oxygen theory wasn't developed sooner was technological limitations, not intellectual ones: scientists simply didn't have any way of preparing pure oxygen to experiment on before Priestly.

(FYI, I just happen to know all this because I'm in the middle of preparing a series of lectures on the history of science, and I just finished the segment on the atomic theory. It's a really fascinating story.)

</comment></comment></comment><comment><USER18> It is fun to read these things, and of course discussion is a good thing, but I do hope that blogs and comment sections do not end up serving any formal role in the scientific literature.

There are several reasons for this: a blog's visibility is low compared to a preprint server (in the scientific community at least), the contents of the blog probably won't be as well-preserved, and there is a tendency to be more casual with the arguments.

<comment><USER19> > I do hope that blogs and comment sections do not end up serving any formal > role in the scientific literature.

Why not? It all depends on the qualification of the people writing blog posts and comments. Remember that some 300 years ago a lot of scientific results existed in epistolary form only, and that first journals that looked like today's thing (like the Bulletin of the Royal Society) were basically compilations of letters sent by astronomers, naturalists etc and reactions of their peers sent as follow-up letters.

Naturally, this doesn't mean that anybody and their dog should have a voice in discussing matters like cosmology if they actually have no clue about it.

<comment><USER18> The continuation of the system you mention still exists today, and is the main channel of scientific discourse. I think it is a better channel to use when challenging someone's work.

(I don't agree with your statement that it depends on qualifications -- I don't think qualification is a measure of the importance of a contribution.)

</comment></comment></comment><comment><USER20> > These equations tell you that like masses attract and unlike masses repel. > We don't normally talk about this because for all we know there are no > negative gravitational masses, but you can see what happens in the Newtonian > limit.

I feel like I am misunderstanding what the author wants to say here. It seems to me that this would only be the case if you change the sign of the gravitational mass (F[-m_1,-m_2]=F[m_1,m_2]), but not of the inertial mass?

In the Newtonian case you get that the force is proportional to m_1 _m_2, so +_ +=+, + _-=- and -_ -=+, but then F=ma flips the direction of the acceleration, right?

+ _\+ gives F >0 and a>0, so attraction.

-_\- gives F>0, but negative inertial mass yield a<0 and hence repulsion.

+*- gives F<0, so the positive inertial mass sees a<0 and is repelled, while the negative inertial mass sees a>0 and is attracted.

What am I missing here?

</comment><comment><USER21> Tone of this blog post is extremely pedantic and comes across as if the author were personally insulted by the paper.

But her argument is basically "You didn't understand the math, and you misunderstood the work that you cited".

I feel like the burden is a little higher -- i.e. put in some effort to at least show the readers the math she's talking about and the counterfactual conclusions they arrive it if worked out.

I would be much more convinced if she took the original paper's claims at their strongest and most convincing and formulating a simple proof or mathematical argument why the paper is wrong -- instead it feels like she's knocking down a straw man and saying "you're too stupid to be doing this kind of work"...

<comment><USER22> The argument presupposes that a person either believes (if they're not a physicist) or knows (if they are) that a spin-2 field must obey those rules, and that gravity is a spin-2 field, which makes the conclusion follow naturally.

The math for this would not make any sense to a layperson, but is widely accepted. Proposing a new theory of negative mass means proposing much more significant alterations to the underlying theory of gravity; the theoretical machinery supporting this current understanding is huge.

<comment><USER21> True. I'm not a physicist, so help me understand -- we've only ever observed fermions with spin 1/2 and bosons with spin 1 (and recently, Higgs at 0). We've postulated that gravitons would have to be spin-2 because of how the math works out (I don't understand the math but wikipedia suggests that its because gravity is defined by the use of 2nd order tensors) but we've not confirmed the existence of gravitons. Hopefully I'm not talking past you by speaking of particles, correct me if I'm wrong but particles/fields are interchangeable as a matter of quantization, right?

I definitely trust the general relativity math -- gravitational lensing /GPS atomic clock corrections are perhaps the easiest bits to wrap my head around as evidence.

Anyways, all that is to ask the question -- Is this negative mass model in conflict with observations or is it in conflict with other models of those observations?

<comment><USER22> I am not an expert on this either, though I guess I hope to be someday. But when Hossenfelder says that Spin-2 necessitates like charges attracting, I believe her. I've also heard that result elsewhere.

My understanding is that the spin of a field or particle is more of a result of the equation (specifically, the Lagrangian) which governs its dynamics. This is irrespective of whether you consider it as a field or as a quantized particle of that field; either way the Lagrangian has certain symmetries. The Fermion Lagrangian has symmetry on 4pi rotation, but not 2pi, which (confusingly) we call spin-1/2\. I suppose that the GR Lagrangian has symmetry under pi rotations, which corresponds to spin-2.

(that would make sense if the stress-energy tensor is contracted with two vectors; it would essentially boil down to the fact that (-x^T) M (-x) = x^T M x if you wrote everything as matrices. But while I have studied GR I haven't studied it as a field theory so I'm not sure it's this simple.)

So the Spin-2 thing is not too questionable. I don't anything about how to turn that into a statement about gravitational charges, though.

</comment></comment></comment></comment><comment><USER23> "highly problematic to introduce negative inertial masses .... This fits badly with our observations."

Science news is not scarce. Click-bait titles aren't either. There's no shortage of catchy on-paper theories that 1)are not backed by evidence, 2) make no predictions.

Cosmology has a big problem, and thrashing around in desperation is not becoming.

</comment><comment><USER24> Negative matter is created spontaneously everywhere, according the article in theconversation.com. Why then can't we collect it, isolate it, and poke and prod it? Because the particles are too small and interact too weakly?

<comment><USER25> > _the particles are too small_

That's not a good way to talk about these things. Usually it's the really small stuff that is very strongly interacting - see quarks.

> _and interact too weakly_

That's better.

</comment></comment><comment><USER26> Obligatory XKCD: [https://xkcd.com/955/](https://xkcd.com/955/)

When you read breathless science journalism about the latest revolutionary paper, remember how it usually works out. Enjoy it as entertainment if you wish, but don't get your hopes up.

<comment><USER27> Reminds me of the SUSY bets.

</comment></comment><comment><USER28> Well, the negative consensus is disappointing, but the criticisms are absolutely massive.</comment>


Mysterious heart damage, not just lung troubles, befalling Covid-19 patients - <AUTHOR> https://khn.org/news/mysterious-heart-damage-not-just-lung-troubles-befalling-covid-19-patients/ <comment><USER2> This headline is definitely a lot scarier than the actual body of the study.

The most likely cause of the heart damage by far is the systemic inflammation induced by pneumonia. We know this because pneumonia patients of all types often have heart strain afterwards[1]. But that damage is very rarely permanent as the risk subsides back to baseline given enough time.

Until we see evidence of heart issues in patients without pneumonia complications, we shouldn't be any more scared of covid-19 as we were before. In particular young and healthy people still have very little risk from infection. Patients who recover without serious complications should not be afraid of hidden heart damage.

[1] [https://www.health.harvard.edu/heart-health/heart-attack- ris...](https://www.health.harvard.edu/heart-health/heart-attack-risk-rises- after-a-bout-of-pneumonia)

<comment><USER3> Hospitalization rates for people aged 20-44 are in the range of 15% to 20%. You might want to read up on the experience of COVID-19 hospitalization before you decide that there's little risk from infection.

[https://www.statista.com/statistics/1105402/covid- hospitaliz...](https://www.statista.com/statistics/1105402/covid- hospitalization-rates-us-by-age-group/)

<comment><USER4> That is percentage of confirmed cases that wind up with hospitalization.

However we mostly don't try to confirm cases if it won't affect the care we give. We just tell them to self-isolate. We therefore will not have good statistics on what percentage of cases are confirmed until after the immediate crisis is over and we test to see how many have antibodies.

So your figure is, "Of young people who have it severely enough to get tested, 15-20% get hospitalized." This says nothing about what fraction of cases are severe enough to get tested.

Also note that we undercount deaths. If a person dies and was never confirmed to have COVID-19, they are also not counted as a COVID-19 death. Nobody knows how big this undercount factor is.

<comment><USER5> All good points. But paulsutter's message remains: young people are at significant risk. Yes, the risk for older people and those with pre-existing conditions in higher. But the parent poster's characterization of the risk for young people as "very little" is dangerous.

<comment><USER6> This is also why I don't really like that some propose various "herd immunity" schemes - we simply don't know what the virus actually does to people in practice, even if it does not outright kill them. So it seems very irresponsible to propose schemes like that at this point in time.

<comment><USER7> Exactly. I know I'm waiting until they have herd immunity available for everyone.

</comment></comment></comment></comment></comment></comment><comment><USER8> So, I've been battling this bug for the last three weeks or so, probably caught it on the way back from my last job in Finland. I expected an empty plane instead it was packed like it was the last train out of San Fernando and everybody was scared there never would be another one.

After a week or so symptoms started in spite of having self-isolated already after the flight, so that's why I figure that is where I caught it, no positive confirmation because tests are still pretty rare around here but all the symptoms are present. At least I hope that I did not infect anybody else by taking that precaution. One thing I noticed (besides the hacking cough that does not seem to want to go away) was a pretty highly elevated heartrate at rest. Up to 20% higher than normal.

I already had some lung damage to my right lung due to an earlier pneumonia, but also played saxophone which does a good job of teaching you how to breathe properly and may improve your lungcapacity a bit.

The last couple of weeks have been a continuous rodeo of improvement and falling back again, today is the first day that I have a bit more energy, other than that the time over the last weeks was mostly spent sleeping.

Today is the first time I've seen my heart rate at rest below 60, and I take that as a very good sign that I'm on the tail end of this.

Wouldn't wish this on my worst enemy.

If you can avoid this bug you really should. I totally believe that if I had had a worse general condition that I may have ended up in the hospital, and given the extra strain on the heart I find the heart damage not so much mysterious as logical. After all, if your lung capacity decreases due to fluid in your lungs then your heart and chest muscles will have to work harder (possibly _much_ harder) to get your blood O2 levels to saturation (if they still can...).

<comment><USER9> There is a hypothesis [0] that the virus attacks red blood cells and impacts their capacity to transport O2, and that the lung damage is actually caused by that, and not directly by the virus. Elevated heart rate makes a lot of sense.

[0] see thread and linked paper: [https://twitter.com/yishan/status/1244717172871409666](https://twitter.com/yishan/status/1244717172871409666)

<comment><USER10> > There is a theory [0] (unproven!)

Would it be more appropriate then to call it a hypothesis?

<comment><AUTHOR> No, "theory" is simply a provable "hypothesis". Doesn't have to be proven, just provable.

The thing is, a theory can never be completely proven. We can never completely discount the possibility of making a new observation or experiment that disproves the theory (hence "falsifiability").

That's why, for example, the "germ theory" is a correct term, even though its probability of being correct is so close to 100% that we could just call it the "truth".

</comment></comment></comment></comment><comment><USER11> Random speculation aside, if you (like me) are currently at the tail end of COVID-19 and beginning your convalescence from it, it's wise to assume you have some degree of myocarditis and behave accordingly - that is, as best you can, avoid activities that may strain your heart and circulatory system for a couple weeks to a month following end of active COVID-19 symptoms.

I'm not a doctor, and this isn't medical advice, but it isn't alarmism either. It's well known that pneumonias, however caused, tend to be rough on the heart. So it's just common sense to regard this pneumonia the same way.

Look at it this way. If you aren't at risk, but assume that you are, the worst that happens is nothing. If you _are_ at risk, and assume that you _aren 't_, you may well not be so lucky. So, especially when you may not be able to rely on the usual degree of hospital support - better safe than sorry.

</comment><comment><USER12> One factor to consider: Some folks will be absolutely _terrified_ to learn they have this disease, which may have real effects. An example: [https://en.m.wikipedia.org/wiki/Voodoo_death](https://en.m.wikipedia.org/wiki/Voodoo_death)

"These data suggest that vagus contributes to severe emotional states and may be related to emotional states of immobilization, such as extreme terror. Unfortunately, this immobilization technique is potentially life-threatening for mammals (but not for reptiles). Mammals would undergo states of bradycardia or hypoxia as an over-activation of parasympathetic vagus system. The organs of the oxygen-hungry mammal are deprived of oxygen due to lack of blood flow, and the animal dies."

<comment><USER13> That implies a low heart rate causing death, correct?

If so, this would be an easy hypothesis to test based on heart rate.

But also, do the rats in voodoo death have heart damage? These covid patients do. If the rats don't, then you're quite off track.

<comment><USER12> It's just one example of a heart-related effect, that's all. Considering that we're all here reading another hypothesis that this is the first-ever respiratory pathogen to _infect the heart_ , it doesn't seem that much of a stretch.

We totally should research whether fear can lead to physical heart damage, but I would bet that "stress in general" is the source of this damage, not only emotional stress. See:

[https://www.medicalnewstoday.com/articles/295664](https://www.medicalnewstoday.com/articles/295664)

[https://www.medicalnewstoday.com/articles/317478](https://www.medicalnewstoday.com/articles/317478)

</comment></comment></comment><comment><USER14> let me preface this by mentioning that i havent been tested for covid-19.

two weeks ago i've been having real issues breathing. it felt like my upper body was borderline paralyzed and i had to really force myself to fully breathe in. this wasn't constant but happened every day for several hours each. especially at night.

i got worried that i might have the virus so i checked my temperature and oxygen blood saturation as well as my pulse.

temperature was fine (36.6°C-37.2°C), blood saturation was in the normal range, however it dropped from 97-100 when i wasnt having any issues to 94-97. my pulse rate however went from usually ~75-80 to >110 whenever i had breathing problems.

it went away last week.. or so i though. i had another episode of that this morning, it was only for 3 hours today, however. it seems to be going away, but if it actually was (or is) the virus... it seems plausible to me.

but i'm a person without any medical knowledge so ... listen to the people actually treating the patients, not random armchair specialists like they're frequent on hacker news -- especially in threads about covid-19.

<comment><USER15> You could be having panic attacks; based on the fact you've got numbers, it sounds to me like you're actively monitoring your own blood saturation, which already implies you may be worrying too much about things like that. Don't underestimate the effects of worry and stress. If it's temporary and you don't have other symptoms then you probably don't have the virus.

<comment><USER16> I'm not a doctor, but each time I hear about a possible diagnostic about panic attacks, it feels like somebody tells a patient having a rhinovirus "your symptoms are explained by the runny-nose illness!". I.e. just stating the symptom (sympathetic/parasympathetic system going weird, heart too fast, etc) but phrasing it as if it was found to be the cause.

<comment><USER17> I mean, panic attacks have no "real" cause by definition. They are your body overreacting in response to a perceived threat that isn't really there; they are a type of cognitive distortion. If a panic attack was in response to a "real" cause, it wouldn't be a panic attack, it would be a normal response to a threat.

<comment><USER16> I know, but look, it is not the correct behavior of the body, right? So obviously something is wrong, and I find it hard to believe that the problem is from the mind if the patient is not himself stating it. In most cases, if he has an anxiety problem, he would straightly start by talking about it, like "I have been in wrong terms with my neighbors for years, and now just thinking they are next door is hurting my chest and making me hard to breathe"...

I admit that in some cases the problem origin could have been repressed, but this is not very common.

<comment><USER18> > "I have been in wrong terms with my neighbors for years, and now just > thinking they are next door is hurting my chest and making me hard to > breathe"...

Not at all. Anxiety is hearing the boss music in a video game and not seeing any enemies. I'll often find myself so tense I'm holding my breath with no ability to rationalize why I'm in that state. It's a real bastard.

<comment><USER16> You're right. So (I agree with you but from here I'm trying to think about some path to search an explanation) maybe could it be explained by some long- term learning of the body-mind connection under repeated stress situations (like being in a crowd while being self-conscious), and then it repeats itself without the obvious stimulus?

What I resent, actually, is when physicians are presented with a package of somatic symptoms and sympathetic/parasympathetic symptoms, and readily discard the somatic part in order to jump to the "panic attack" conclusion.

</comment></comment></comment></comment></comment></comment></comment><comment><USER19> Scroll down to figure 1. Non survivors end up with cardiac and kidney injury. Interesting that this might shine light on the cause.

[https://www.thelancet.com/journals/lancet/article/PIIS0140-6...](https://www.thelancet.com/journals/lancet/article/PIIS0140-6736\(20\)30566-3/fulltext?fbclid=IwAR3Hyjh3ax53XAGCxWpC3aNWx1k8_VEPxiOlfptMkVUinaN_MWHodgsIy1k)

<comment><USER20> Thanks. Specifically, from your citation:

"In addition, angiotensin converting enzyme 2, the receptor for SARS-CoV-2, is expressed on myocytes and vascular endothelial cells, so there is at least theoretical potential possibility of direct cardiac involvement by the virus"

The most sane hypothesis I've seen is that the virus will attack any cell with the ACE2 receptor, including the heart and kidneys:

"Angiotensin converting enzyme 2 (ACE2) is an enzyme attached to the outer surface (cell membranes) of cells in the lungs, arteries, heart, kidney, and intestines."

This would require the virus to enter the bloodstream from the lungs, which is possible after sufficient alveolar damage.

ref: [https://en.wikipedia.org/wiki/Angiotensin- converting_enzyme_...](https://en.wikipedia.org/wiki/Angiotensin- converting_enzyme_2)

As an aside, although Wikipedia doesn't mention it, testicular cells also express ACE2, leading to some worry about downstream fertility effects:

[https://www.medrxiv.org/content/10.1101/2020.02.12.20022418v...](https://www.medrxiv.org/content/10.1101/2020.02.12.20022418v1)

<comment><USER21> Interesting point about the ACE2 receptors in the GI tract. I wonder if that's why certain infections present with GI symptoms?

</comment></comment></comment><comment><USER22> There is a paper circulating that claims that the virus impedes red blood cells leading to organ failure including lungs, and not the other way round.

<comment><USER23> Do you have a link?

<comment><USER24> [https://chemrxiv.org/articles/COVID-19_Disease_ORF8_and_Surf...](https://chemrxiv.org/articles/COVID-19_Disease_ORF8_and_Surface_Glycoprotein_Inhibit_Heme_Metabolism_by_Binding_to_Porphyrin/11938173)

Among the speculation is that a blood transfusion may be a viable treatment.

</comment></comment></comment><comment><USER25> Disclaimer: I'm not a medical professional.

My understanding is that myocarditis is a possible, albeit rare, complication of many viral illnesses?

Additionally, respiratory failure causes a massive strain on the heart, so it's not hugely surprising that many patients would have heart complications.

It would be interesting to know how many patients without respiratory distress develop these cardiac symptoms.

</comment><comment><USER26> There are ACE-2 receptors all over the heart.

<comment><USER27> [https://www.youtube.com/watch?v=jAW6VBWTiAA#t=36m](https://www.youtube.com/watch?v=jAW6VBWTiAA#t=36m)

ACE2 is also found in several other organs in which they are seeing multiple organ failure with this virus so it likely is can bind to them and contribute to damage in these organs including the heart but as OP says there are multiple ways the heart could be affected

Loss of ACE2 receptors in the heart can cause impaired heart function

[https://www.youtube.com/watch?v=jAW6VBWTiAA#t=8m](https://www.youtube.com/watch?v=jAW6VBWTiAA#t=8m)

<comment><USER26> Also there is a close connection between the heart, kidney, kidneys and other organs.

For instance, ACE1 and ACE2 receptors are involved in a complex hormonal system that manages your blood volume, blood pressure, etc. Antihypertensive drugs target this system at different points. (ACE inhibitor drugs such as Lisinopril target the ACE1 receptor and don't bind much to ACE2 at all)

Liver failure can present with symptoms similar to asthma because if your kidneys can't get rid of water, the water will leak out of your lungs.

I had a friend who passed away last year from a bacterial infection that got to his heart. We all have bacteria that live on our skin without problems, but if you get a wound they can get into your blood and go to your heart.

He had heart valve damage which is bad because if your heart valves work improperly, it can damage your blood the way you can 'damage' cream by whipping it. This can cause clots to go into your lungs or your brain with bad results either way.

He had open heart surgery but they had a hard time restarting his heart and he was in a coma for a few months before they removed his feeding tube.

One reason why penicillin was a miracle was that all sorts of people who got even minor wounds (e.g. soldiers, children, farmers, ...) would progress like that before WWII.

</comment></comment></comment><comment><USER28> Was reverse causation considered? Those with some heart damage are more likely to be tested and hospitalized for COVID-19?

<comment><USER25> Article addresses this

</comment></comment><comment><USER29> There's a growing body of evidence that C19 attacks hemoglobin in the blood, with the effects similar to malaria (where the parasite uses hemoglobin as a nutrient source): blood with depleted hemoglobin simply can't carry as much oxygen, so people start gasping for air, their lungs swell, and then pneumonia kills them. Crucially, gasping for air seems to happen well before the onset of pneumonia. This also explains why diabetics are more severely affected.

If that's the case, ventilators aren't going to help if you use air in them, without supplemental oxygen: even if you pump air into the patient's lungs, their blood simply won't be able to carry sufficient oxygen. You need to supplement with oxygen.

It also explains why (hydroxy)chloroquine helps: if it stops/reduces depletion of hemoglobin (which it does [*]), the patient may never progress to pneumonia, because their blood is able to carry sufficient oxygen.

For those who already have pneumonia, supplemental oxygen would be vital if they also have C19. Standard ARDS treatment protocol will not work well.

[https://chemrxiv.org/articles/COVID-19_Disease_ORF8_and_Surf...](https://chemrxiv.org/articles/COVID-19_Disease_ORF8_and_Surface_Glycoprotein_Inhibit_Heme_Metabolism_by_Binding_to_Porphyrin/11938173)

</comment><comment><USER30> It's not "mysterious". Myocarditis is a common result of viral infections of any kind, and can persist for weeks after recovering from the virus itself.

</comment><comment><USER31> I wish these articles would be more specific about what they mean by "pre- existing heart conditions". I have slightly high blood pressure which has been known to enter hypertension territory before (by like 1 point), but I think mostly stays a bit below there. Never know how worried I should be.

</comment><comment><USER32> is this 1 in 5 in people who are otherwise asymptomatic as well? I guess not, or we would be seeing a lot more dead but I wonder if there are any heart attacks occurring in otherwise asymptomatic people and not being marked down as Covid-19 related.

<comment><USER33> I just had a family friend die of a heart attack with no covid symptoms - definitely a scary time

<comment><USER34> A (distant) friend shared he lost his wife to hearth attack a couple of weeks ago out of the blue. I figure(d) it was random.

</comment></comment></comment><comment><USER35> This might be the reason: Covid-19 attacks the 1-beta chain of hemoglobin to inhibit human heme metabolism link: [https://chemrxiv.org/articles/COVID-19_Disease_ORF8_and_Surf...](https://chemrxiv.org/articles/COVID-19_Disease_ORF8_and_Surface_Glycoprotein_Inhibit_Heme_Metabolism_by_Binding_to_Porphyrin/11938173)

</comment><comment><USER36> ACE2 (the entry point for the virus in the lungs) is expressed in the heart too, so it makes sense that the virus could attack the heart directly.

It could also be a side effect of chloroquine.

Frustrating how little we know at this point.

</comment><comment><USER37> There's so much blind speculation in this comment section. The kind that's intriguing and fun when it's about engineering/math/whatever, but dangerous when it's about the health effects of an ongoing pandemic.

I hope moderators do something about it.

<comment><USER25> Can you explain how exactly it is "dangerous"?

<comment><USER38> Speculation on treatments for Covid-19 has already killed people: [https://ktla.com/news/arizona-man-dies-after-taking-form- of-...](https://ktla.com/news/arizona-man-dies-after-taking-form-of- chloroquine-used-for-aquariums-in-apparent-attempt-to-treat-coronavirus/amp/)

<comment><USER15> Speculation is fine; this guy died from self-medicating. There is a difference. We shouldn't resort to censoring to protect stupid people.

</comment></comment></comment></comment><comment><USER39> It's interesting that the chloroquine has possibly been linked to cardiac arrest. Is is chloroquine, or possibly the virus that is causing? Or maybe both in combination?

</comment><comment><USER40> I wonder if the patients get too much hydroxychloroquine. It can couse heart failures.</comment>


Machine Learning Projects for Mobile Applications - <AUTHOR> https://itbook.store/books/9781788994590 <comment><USER2> Every submit for this site is just a daily ad for Amazon affiliate linked books (tag=itbook.store-20). A new ad is submitted every day, like clockwork.

There is no "store". Even the descriptions are ripped from Amazon's pages.</comment>


A Senseless Conversation - <AUTHOR> https://sites.google.com/site/asenselessconversation/

<comment><USER2> Nice short story. For a full sci-fi book of this genre, check out _Permutation City_.

For another fun question: "What time is it?"

And lastly a quote: "The effort of using machines to mimic the human mind has always struck me as rather silly: I'd rather use them to mimic something better." ~E.W. Dijkstra

<comment><USER3> better yet, also Dijkstra, "The question of whether a computer can think is no more interesting than the question of whether a submarine can swim."

<comment><USER4> We are complex machines, aren't we?

</comment></comment></comment><comment><USER5> Fitting. Just a few minutes before reading that I had one of those "Contemplating your hands" epiphanies. I sat down in my computer chair, reached over to my mouse and came to a dead stop. A thought had brought itself to the foreground.

"I can't feel myself move."

Now when I say this I don't mean a numbness, or loss of the senses. But I couldn't discern what exactly I was doing that made my arm move. Or any other part of my body for that matter. That was silly of course, I move them all the time. So I tried moving them slowly, and felt a slight sensation.

Of course I thought; the slight sensation isn't _really_ the feeling of moving my arm, it's the feeling of matter like air brushing against it. After all, I am basically sitting in a tank of atmosphere. Nerves report _state_ , but aren't really projecting the feeling of movement.

That thought chain quickly led to a minor existential freakout. (During which I puzzled over the question of how the hell I move at all.)

I eventually generated three hypotheses:

1) The feeling of movement simply isn't reported by nerves. Introspection can't discern your cognitive processes, so why should it be able to your physical ones?

2) The feeling of movement is so faint that its overshadowed by the mere touch of air/one's own body hair. I know that when I'm in the deepest state of somnolence just before sleep; it's very often for me to realize I need to get up to do something, and struggle against the inhibitions on your movement somnolence induces before sleep. I can feel the struggle of this, it also feels the same if you try to fight sleep paralysis. One could argue that this _is_ the feeling of movement.

3) You could argue that the feelings reported by nerves about the state of your environment _are_ the feeling of movement. After all, feelings are just signals sent by nerves and interpreted by the brain. These feelings are generated by movement, and thus _are_ indeed the feeling of movement.

4) My understanding of cognition is too incomplete to even hypothesize something remotely plausible.

Now, considering that so many articles on sleep studies mention them, I'm sure that the mechanics of how the brain controls the body are well understood and that if I'm truly curious I can google it. (Which is something I might just do.)

But the real reason I shared that anecdote, besides being semi-relevant to the topic at hand. Is because I took my ability to move for granted. In the same way that I take the idea that we could all be a simulation for granted. I've considered that a non-zero possibility for quite some time now.

I'll admit that I read some of the comments here before reading the story. (A big no no for science fiction, a genre that thrives on twists.) And after glancing at Tichy's comment, was afraid I might have spoiled it for myself. However, the journey is more important than the destination, so the concept of such a twist automatically made me go read the story. I was thoroughly disappointed with the ending.

The concept of a memory loop isn't really new. (I've seen it mostly explored in the context of time travel, but still.) But trapping a human in a text interface and presenting it as the thinking machine? Morbidly delicious. (In all the right ways.) And useful too. I could pull it out any time someone exhibits signs of having decided that a computer program can't be conscious simply by virtue of not being implemented on a human brain.

Having a human brain with no senses hooked up presented as a computer program would really drive home the message.

EDIT: Regarding the story, my immediate thought after finishing was questioning why if the program panicked because it lost all it's senses, why didn't he simply swap out the memories of J. Random. Person. With someone who already accepts that they might be a simulation. I'm sure that if they really believed that, it would be possible to calm them down by explaining that they are a simulation of themselves. And for bonus points, if someone were to consent to have their memories used for this (It isn't stated how he actually _got_ the memories mind you.) that they would already have the possibility of being the simulation strongly in their head. And would eventually accept that they are a non-human.

Though, if _you_ consent to something like this, you essentially ensure that you can never be sure weather your you or a replay of your memories. Though as it stands, you can't really determine this already. Which makes for one of those classic thought experiments that still has mileage.

Trains of thought down this road are probably inherently unresolvable, but still fun to try.

<comment><USER6> _The feeling of movement simply isn't reported by nerves_

Bzzt...

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

<comment><USER5> First and foremost, you sir are awesome.

So number two was closest. (And what I figured. Though I have to say that ahead of time for it to count.)

One of the things I love about the answers to questions like this is the amount of interesting stuff you learn. At first (before I'd read the article) I thought you were being a bit harsh. It WAS a hypothesis after all. But after reading that it was so obviously far off the mark I had no trouble seeing why that sentence got the buzzer.

This in particular caught my eye:

"The proprioceptive sense is often unnoticed because humans will adapt to a continuously present stimulus; this is called habituation, desensitization, or adaptation. The effect is that proprioceptive sensory impressions disappear, just as a scent can disappear over time. One practical advantage of this is that unnoticed actions or sensation continue in the background while an individual's attention can move to another concern."

Which would probably qualify for "Overshadowed by virtually the slightest application of any other sensual input."

Back to the Turing Test however. One of the things I like to do when I'm bored is get on Omegle. Now, my goals are different from 95% of the other users on there. I wade through the sea of wankers until I find someone who actually wants to talk. I then to proceed to:

A) Attempt to convince them that I am a machine.

B) Convince them that they're a machine.

(Obligatory XKCD: <http://xkcd.com/329/>)

So far the tally is something like: I've convinced two people of my non- humanity. And B hasn't happened yet. Which brings me back to this story. The moment I finished it, after the thought about getting the memories of someone more compatible with the idea of a brain simulation, my face formed a mischievous smile.

I thought "This will be great for the next time I get on Omegle."

</comment></comment></comment><comment><USER7> Does anyone remember a thread of comments on HN a year or two ago where a guy was placing bets that he could totally swing your opinion on giving a sentient AI freedom? Supposedly he convinced everyone and won every bet but no-one revealed what he did and I thought this was going to be a posting of one of those conversations at first ;-)

<comment><USER8> Sounds like the ai box experiment: <http://yudkowsky.net/singularity/aibox>

<comment><USER7> Wow, I never realized it was _that_ old but that's the one - thanks!

<comment><USER9> It has been discussed on HN more recently: <http://news.ycombinator.com/item?id=3324152>

<comment><USER10> Somewhat recently, someone attempted it with the intention of reposting the log. However, he failed: <http://lesswrong.com/lw/9ld/ai_box_log/>

<comment><USER9> Saying "here are next week's lottery numbers" would not convince me.

Suppose I am outside the box and the AI is inside the box, the AI cannot have a perfect model of the lottery machine or of me. At best it has seen photographs. All photographs are noisy. There will always be some detail it does not have that would invalidate the simulation (e.g. I have a minor injury that I have never talked about and is not visible in any photo, an ant crawled into the lotto machine last night, etc.)

If it has sent drones to physically inspect the internals of the machine or my brain, then it is already out of the box, so my decision is irrelevant.

If I buy a lottery ticket, there are four possible outcomes.

1\. I don't win (or I die before I can claim my winnings, the draw is declared invalid etc.)

2\. I win, but it is a coincidence (maybe it was worth a shot for the AI, but my odds of winning are no better than they would be without the AI's help.)

3\. I win with the AI's help, because the AI is already outside the box and has rigged the draw by modifying the machine, or just inspected it closely enough to predict the draw.

4\. I win (or believe I win) with the AI's help, because I am inside the box.

#3 and #4 should not affect my decision (whether I like it or not, the AI is out of the box or I am in the box with it and unable to let it out.) So I dismiss them.

But the relative probabilities of #1 and #2 are the same as if I bought a ticket without consulting the AI (which I would not normally do.)

<comment><USER10> The AI was not let out of the box, and you're saying that it wouldn't convince you? This only sounds like an argument that Eliezer was right in not posting his logs.

</comment></comment></comment></comment></comment></comment></comment><comment><USER11> I was imagining an alternative version in which Douglas later reveals that he was not participating at all in the conversation; his computer was covering for him. Good read; thanks for sharing.

<comment><USER12> I had exactly the same thought at first, that douglas was just sitting watching his friend talk to the computer. The sensory tank was the most unbelievable part for me it seems like there would be a better way to handle that. Anyway thanks for an interesting read.

</comment></comment><comment><USER13> Could also be a horror story about a human in a tank who was made to believe it is a computer. The whole tank could then be presented as an intelligent machine.

<comment><USER14> It occurred to me that this could be used as a dominance/brainwashing technique. Break a person's believe in his own free will and humanity and they will have little reasons to oppose you, the creator.

<comment><USER15> I don't think it would work.

People's sense of "self" can't be taken away, it is something we develop the moment we realize our thoughts are private and others can't give us what we want unless we ask for it. Children learn to lie very early; even when their language skills aren't sufficient, they learn to fake disappointment & force themselves to cry to get what they want.

IMO, even under prolonged captivity & complete dominance, humans only _submit_ to subjugation, but they never lose their sense of Self.

Higher-level indoctrination is even less plausible. Nearly all religious groups & cults have the human at their center. People have to willfully submit to hypnosis.

Going back to the development of self, I think another thing that makes it possible is the position of our eyes. We can only see in < 180 degrees, our eyes open & shut, and we happen to fall asleep. If the human subject was allowed free movement, the captor would want us to respond to commands .. we would need to be called .. differentiated amongst ourselves. Human Unit 1 is different from Human Unit 2. The captor _calls_ the subject, and the subject chooses to respond, somehow. In the presence of punishment, the subject _decides_ to carry out assigned duties to avoid punishment, or to gain reward: self-interest. Self.

<comment><USER16> > IMO, even under prolonged captivity & complete dominance, humans only submit > to subjugation, but they never lose their sense of Self.

Actually, it can be done. Depersonalization is relatively common: <http://en.wikipedia.org/wiki/Depersonalization>

<comment><USER15> Excellent, thank you for the pointer.

However, do depersonalized people feel like they're no longer individuals, or do they feel like they no longer have control?

<comment><USER17> they feel that they are somewhat detached from their physical selves... sort of like an observer, watchingyourself go through theday. its an odd sensation.

on another not to parent posters..... whether or not our sense of self is ongoing and inbreakable is certainly not decided or anywhere near scientific fact(yeah yeah, science only disproves, you know what i mean)...

all we can say is that we feel as if we have this continuity..... and that it apprars as if others feel the same way. memory is not like tape.... your sense of timing and events changes constantly, and what you perceive to be your unbroken, continuous sense of self and its memories is, in fact, almost universally incorrect on all kindsof things as it changes over time.... butyou (and i) will feel everything is in order. it is likely constantly teconstructed ad a survival trait.

Also look at surgical anaesthesia.... some theories on this, and subjectively i can see it, while you are under, you arent asleep...... you, your sense of self is gone, totally shut down. no dreams. no sense of how much time had passed when you wake........ not like a regular sleep whenyou at least havesome idea. it always feels like instant teleportation from the surgical suite to the recovery room, even if many hours have passed. then there arethepeople who just never come back.

we are far away from understnding consciousness... which is cool. weve batelyscratched the surface. were just nowrealizing the brain has far more plasticity than we thought a few years ago.... its still a hugemystery.

now take general anaesthesia...... during surgeries i can recall, i was simply gone. that time was simply time i didnt exist.

<comment><USER15> Interesting comments. Like the typos too :-)

</comment></comment></comment></comment></comment></comment></comment><comment><USER18> Sam Hughes wrote the same story 3 years earlier and I think I like his version better: <http://qntm.org/difference>

<comment><USER13> You could submit that as a story for some easy karma, just saying... Liked it.

<comment><USER19> Is easy karma worth it?

</comment></comment></comment><comment><USER20> Several thousand years later... <http://www.terrybisson.com/page6/page6.html>

</comment><comment><USER21> The story went off the rails for me when "Zach" said he couldn't hear himself nor feel himself move. Even in the midst of the most severe sensory deprivation, I continue to perceive "noise" in my sensory system: tinnitus, breathing, heartbeat, sub-resolution sparkles in my visual system (just close your eyes and pay attention), kinaesthetic sensations of enormous number and variety. As long as you're going to recreate memories indistinguishable from reality, you'll further need to create sensory input indistinguishable from reality. At which point you've simulated the entire encounterable universe and you indeed have something that I would call intelligent, despite its lack of carbon components in the mental mechanism. Each component technology might be interesting for its own sake, but aside from the philosophical point, what's the use? The carbon based versions are plentiful, and the construction process...

<comment><USER8> It's a thought experiment. It's not impossible to imagine a perfected sensory deprivation tank where you do not hear yourself move or breathe. The other stimuli are, from what I understand, hallucinations, and as such are irrelevant to the experiment.

> As long as you're going to recreate memories indistinguishable from reality, > you'll further need to create sensory input indistinguishable from reality. > At which point you've simulated the entire encounterable universe

Not really, after all you only need to simulate the universe at the human level of the perception, which means you can ignore most of the computational complexity of simulating the actual universe.

>Each component technology might be interesting for its own sake, but aside from the philosophical point, what's the use? The carbon based versions are plentiful, and the construction process...

The cabron based forms are not very durable (80 years ? c'mon), they break easily, and don't perform very well...

<comment><USER9> > _The carbon based forms are not very durable (80 years ? c'mon), they break > easily, and don't perform very well..._

Actually it's hard to build machines to last that long (how many 1932 cars are still functional today?)

The real advantage of the machines is that you can switch them off, open them up, replace parts, re-assemble them and switch them on again. You can replace parts of carbon-based lifeforms, but they don't always switch on again and opening them up often results in them being eaten by other carbon-based lifeforms. It's not cheap to do this to old machines, but its fairly reliable.

</comment></comment></comment><comment><USER22> On the subject of the Turing test Turing's actual originally paper is well worth a read: <http://cogprints.org/499/1/turing.html>

It's extremely readable and you may be surprised at how often people entirely miss the point when discussing it.

</comment><comment><USER23> Now the interesting question: How do you know that you are not the result of an experiment of some guy living in a sci-fi world where computation power and storage is extremely powerful? He would put your brain inside a virtual world, and make up all your interactions. The people you talk to, are just a picture, and a sound but they feel real people like you.

We have a brain like Zach have, but instead of being put inside Douglas tank, we are showed (and _sensed_ ) a virtual world. It's a trap, you can't prove that it's not the case.

Douglas also, in your memory, puts some strange definition/notion: infinity. The space and time are both infinite. But does that really make sense? If time wasn't infinite (and began somewhere) then we would know the Douglas trap. He is blocking your knowledge at some point.

<comment><USER24> From Nick Bostrom:

"A technologically mature "posthuman" civilization would have enormous computing power. Based on this empirical fact, the simulation argument shows that at least one of the following propositions is true:

1) The fraction of human-level civilizations that reach a posthuman stage is very close to zero;

2) The fraction of posthuman civilizations that are interested in running ancestor-simulations is very close to zero;

3) The fraction of all people with our kind of experiences that are living in a simulation is very close to one.

If (1) is true, then we will almost certainly go extinct before reaching posthumanity. If (2) is true, then there must be a strong convergence among the courses of advanced civilizations so that virtually none contains any relatively wealthy individuals who desire to run ancestor-simulations and are free to do so. If (3) is true, then we almost certainly live in a simulation. In the dark forest of our current ignorance, it seems sensible to apportion one's credence roughly evenly between (1), (2), and (3). Unless we are now living in a simulation, our descendants will almost certainly never run an ancestor-simulation."

<comment><USER9> My money is on #2.

Once they have switched on an ancestor-simulation, it's probably illegal to turn it off. So it would mean committing the hardware and electricity to the simulation forever. Whatever they gain from running the simulation, they would be reluctant to incur infinite cost in doing it.

<comment><USER25> There is no need for a realtime simulation. What it feels like centuries can be a fraction of second for such hardware.

With this kind of simulations you can obtain, in theory, "what if" universes where alternatives solutions and technologies can be created. If you can observe them and the simulation rate is faster than your own time, it can be a rewarding experiment.

About universe observing, this story is cool: <http://qntm.org/responsibility>

<comment><USER9> I don't think you can simulate your own future, even if you accept #3.

Either #3 is false (and there are no simulations) or #3 is true (and the vast majority of sentient beings live in simulations, which means those running the simulation are probably simulations themselves.)

Yes a computer can run a simulation of an alternate version of itself, but then the speed must necessarily decrease as you go down the hierarchy (as you will see if you try to run one vmware vm inside another.) Or the simulated universe must lag behind the one containing the more powerful (thanks to Moore's law) host computer.

 _Edit_ : unless you have an infinitely-powerful computer like in that story. But then you could argue that every theoretically-possible simulation must be being run by someone somewhere. Good for us even if _our_ society never discovers the infinitely-powerful quantum computer (at least we don't need to worry about being switched off, even if our creators die or their universe collapses.)

</comment></comment></comment></comment></comment><comment><USER26> If you like this sort of AI where people upload their conscienceness to computers and where people's identites/conscienceoness can 'fork', then check out Greg Egan. They have written lots of scifi on this topic.

<comment><USER27> > … check out Greg Egan. They have written lots of scifi on this topic.

I love, and I fancifully imagine that he would too, the idea of referring to Greg Egan as 'they'.

<comment><USER26> "They" can also be used as a (gender neutral) singular third party pronoun in English, and has been used that way since Shakespeare.

<comment><USER27> I am only slightly less amused by the idea that one needs a gender-neutral pronoun to refer to Greg Egan. :-)

</comment></comment></comment></comment><comment><USER28> Well, to be fair, writing an AI that can fool itself into thinking it's a human. Is much easier than writing an AI that can fool an average human. Any inexperienced programmer can write a program that fools itself with less than 10 lines of code.

The reason for that is that one of the problems with the concept of the Turing Test, is it's subject to the intelligence of the tester. A 6 year old boy with no talent in logic is much more likely to think a chat bot is a human, than an experienced CS researcher.

The dumber your tester, the dumber the AI needs to be to fool it. If you write a tester who is dumb as a rock, than it's trivial to write an AI that can fool it.

Zach and Douglas are only going into a lengthy conversation because Douglas went through the trouble of making Zach smart, knowledgeable and mimicking many human behaviors. If he made Zach as smart as a fundamentalist religious zealot. Then he could have just said "you're an AI because I told you so" and Zach would agree. But then again, that wouldn't be slightly as fun.

<comment><USER29> I would find it very hard to tell real humans from bots if we limit environment to YouTube comments.

</comment></comment><comment><USER30> This reminds me of one of my all time favorites games "A Mind Forever Voyaging".

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

It's an interactive fiction game where you play the role of a computer that has only just realised that it's a computer. From your point of view, you've been living a human life with real experiences and a family etc.

The game manual included a great little short story: <http://gallery.guetech.org/amfv/amfv.html>

</comment><comment><USER31> It isn't very helpful to talk about consciousness without defining it in a concrete way, but I think there might be something to that line of questioning.

What about something concrete, like the sensation of pain? I can feel it, and everybody else can probably agree that they feel it too, even if they can't confirm that others do. How would you go about reproducing this sensation in a computer?

It's not clear to me that human thought and experiences can be reproduced by any amount of computer logic and memory. That doesn't mean it's impossible, but I think this is an unresolved question.

<comment><USER32> _What about something concrete, like the sensation of pain? I can feel it, and everybody else can probably agree that they feel it too, even if they can't confirm that others do. How would you go about reproducing this sensation in a computer?_

While your hand, say, might be _physically_ hurt (say, it caught fire), to your brain it's only information coming in that says "now you should feel pain".

You can simulate that in a computer.

</comment></comment><comment><USER33> For a minute there, I really thought he has actually made a reasonable AI machine. Very interesting but disappointing if you were expecting something real. I am still waiting for JARVIS level AI.

</comment><comment><USER34> Readability link (fixes monospace and window-width columns): <http://www.readability.com/articles/b29kmcjg>

</comment><comment><USER35> The rhyme thing tipped me about the ending :-)

</comment><comment><USER36> I wish someone would do this to John Searle. He really deserves it.

<comment><USER37> :)

</comment></comment><comment><USER38> If you found this interesting, Hofstadters "Godel, Escher Bach" (and his second, IMHO more readable book "I am a Strange Loop") explore these ideas in great detail

</comment><comment><USER39> I guessed the ending as soon as he entered the tank but this story still creeped me out :(

</comment><comment><USER40> Computers are somewhere between humans and bacteria on the conscious scale. Biological or mechanical are just two different ways to shuttle electrons around.

I will proudly stand up for the rites of computers as citizens of this country when they exhibit significant signs of ability to choose their own course and have opinions.

The computers will be our children, they will colinate the galaxy, and if we are lucky we can subscribe to the experience streams.

<comment><USER41> I'm not sure that will ever be possible.

Consciousness produces logic as a tool to use. Logic does not produce consciousness.

Computers, by definition, are pure logic and rules. You can use logic to _mimic_ consciousness, but nothing more.

<comment><USER42> > Logic does not produce consciousness.

Considering we have no falsifiable theory about what _does_ produce consciousness, I don't see how you could possibly claim this.

You can't prove that you are conscious, nor can anybody else. I can perceive my own consciousness but I can't rigorously explain it. We have no way of determining if this alleged "consciousness" is a spectrum or binary. We can't test which life-forms are conscious and which are not. We can observe behaviors in animals that seem to imply consciousness, but is a dog conscious, or an insect, or an amoeba? We don't know.

And furthermore, if you believe in evolution, you have to believe that there was no consciousness and then consciousness at some point was created where there was none before. If logic doesn't produce consciousness, what _does_ produce it? And whatever produced it in cellular tissue millions of years ago, who's to say we couldn't likewise produce it in a die of silicon, which like our brains is highly electrical?

<comment><USER43> > And furthermore, if you believe in evolution, you have to believe that there > was no consciousness

Actually, you don't <http://en.wikipedia.org/wiki/Panpsychism></comment></comment></comment></comment>


RubyWarrior - Bloc - <AUTHOR> https://www.bloc.io/ruby-warrior/ <comment><USER2> Very cool! Proud to see that it's made with ImpactJS[1] (my game engine :))

[1] [http://impactjs.com/](http://impactjs.com/)

<comment><USER3> Hey! You made ImpactJS? That's very cool, but it's really hard to commit $99 to buy an engine when I can't even try it! It looks super-rad and I'd love to give it a shot, but it's a bit high of a bar for a casual game dev.

<comment><USER2> If you buy it and don't like it for whatever reason, I can give you a full refund within the first month. That's easier for me to handle than a separate trial license.

<comment><USER4> I never thought about it that way.

Totally stealing that idea.

<comment><USER3> Just anecdotal, but we tried that for a while. Our signups and conversions are much higher with a trial. I work on a SaaS product.

</comment></comment></comment></comment></comment><comment><USER5> Great...but how about turning down the music volume. It's 2:20am here, I opened the page and had a trouser changing moment and woke up the neighbours.

</comment><comment><USER6> Nicely made. Some frustrations:

\- while, until, retry (and others?) not allowed.

\- not being able to see the class of something. Its more ruby style to do 'space.is_a?(Enemy)' than 'space.enemy?'. This would also help to build case statements rather than lots of ifs.

\- no 'print' or 'puts'. How am I supposed to know what 'look' returns when it never really tells me?

\- I prefer a single set of rules rather than adding rules as you go. When first I have to use :backward but later this becomes basically redundant as 'pivot' is added, it just makes me frustrated in having to refactor. Same thing for feel/look.

<comment><USER7> I don't feel `.is_a?(Class)` is ever idiomatic ruby. You should always be coding to an interface, not an implementation. This prevents things like mocks and duck typing, making testing more difficult and adding complexity when you want to add AnotherEnemy that doesn't share the same inheritance tree.

I try to avoid using `.is_a?(Class)` in all of my ruby code when possible. `.respond_to?` is much more responsible way of probing whether an object has the interface you are looking for.

<comment><USER8> > I try to avoid using `.is_a?(Class)` in all of my ruby code when possible. > `.respond_to?` is much more responsible way of probing whether an object has > the interface you are looking for.

#is_a?(class) is a much more specific check of semantics than #respond_to?(method_name). is_a? is the more cautious approach (least likely to produce false positives at the expense of being most likely to produce false negatives) whereas respond_to? is the less cautious approach (least likely to produce false negatives while most likely to produce false positives.)

<comment><USER9> Are you coming from java? That's my background (at least one of them), and felt that way too. Interface === API contract == safe.

But that really isn't the only way to do things. Read up on [http://en.wikipedia.org/wiki/Duck_typing](http://en.wikipedia.org/wiki/Duck_typing)

<comment><USER8> > Are you coming from java?

Well, java was one of the languages I used before Ruby, but I've done more Ruby than Java.

> Read up on > [http://en.wikipedia.org/wiki/Duck_typing](http://en.wikipedia.org/wiki/Duck_typing)

I am well aware of duck typing, and rarely use either #is_a? or #respond_to?

That doesn't change that, _if_ you have a reason to use that type of inquiry to check interfaces, #is_a? is the more safe of the two (more likely to reject an object that provides the semantics of concern and less likely to accept one that does not) and #respond_to? is the less safe (more likely to accept an object that does not provide the semantics of concern and less likely to reject one that does.)

</comment></comment></comment></comment></comment><comment><USER10> This should win every level (given enough tries):

      def play_turn(warrior)
        m = warrior.methods.grep(/.!$/).sample
        warrior.send(m, *([nil, :backward].sample if m != :rest!))
      end

(that sucker of :rest! that doesn't accept a direction argument!)

It's kind of amusing to see the warrior do random stuff like shooting arrows backwards and pivoting back in the worst possible moments. Too bad that Run button repeats the same movements if you didn't edit the source code somehow.

Great game and concept BTW!

<comment><USER11> The sandbox probably always initializes with the same random seed.

<comment><USER10> No, it seems to be a client-side thing. If no edit was made in the code editor since last run it doesn't make the request to [https://www.bloc.io/api/v1/ruby_warrior_players/:id](https://www.bloc.io/api/v1/ruby_warrior_players/:id) (which seems to be the one that returns the warrior and enemy movements). Repeating the same request in cURL multiple times does return different results.

</comment></comment></comment><comment><USER12> Had a lot of fun with my rusty Ruby on this game. Here's my solution to beat level 3 onwards:

[https://gist.github.com/hcarvalhoalves/6096888](https://gist.github.com/hcarvalhoalves/6096888)

</comment><comment><USER4> It would be cool if the game commited your code to a github repo every level.

This way you could see your own progress, and see what solutions other came up with without bugging them.

<comment><USER13> Maybe a gist would be appropriate?

</comment></comment><comment><USER14> Had to implement a

        if not warrior
          return nil
        end

in the play_turn method, to workaround a bug. But other than that, this is great!

</comment><comment><USER15> Akkk... sound... must... turn... off!!!

Ok default sound way too loud, and at least on Safari the little speaker icon in the top left doesn't seem to do anything.

</comment><comment><USER16> I am really disappointed that Ryan Bates is not being STRONGLY credited anywhere on this page... this is just a graphical wrapper on his original creation.

[https://github.com/ryanb/ruby-warrior](https://github.com/ryanb/ruby-warrior)

<comment><USER17> It's in the footer...

<comment><USER16> ah so it is... was below the fold and I didn't see it :-/

</comment></comment></comment><comment><USER18> Feature request: After you've beaten it once let you go through all levels with the same code. Right now it doesn't let you use the features it hasn't told you about.

</comment><comment><USER19> As someone who has never done any development in Ruby. I loved the idea and wanted to use. However what makes it not accessible is that you give no instruction initially on the structure of Ruby syntax. This means that I would need to follow another book or tutorial. Please consider drip feeding the player a syntax cheat sheet that will help with each level .

</comment><comment><USER20> This is VERY, VERY awesome.

As a web-rubyist, this forces me to think in a different way than I normally would.

Thank you for making this.

</comment><comment><USER21> Oh goddamn, this is amazing. As someone who hasn't even seen Ruby code before, you could include a bit more on the syntax of conditional/loop constructs (if/while/etc), but it's amazing. I'll send this to my non-programmer friends right now.

</comment><comment><USER22> It would be great if either `print` or `puts` worked.

<comment><USER18> I have to admit I kind of like that it doesn't. All games have artificial constraints and I feel like keeping you from inspecting too much of the internal state is a reasonable one for this.

<comment><USER23> I would like it to debug my own code. You are more aware of the artificial nature of the variables you create, so it's not as world-breaking to inspect their contents.

I saved a `health_change` variable in my code, and decided what to do based on that, but the warrior did the wrong thing. I wanted to see if my variable was being set correctly by printing it each turn, but I couldn't. My normal tool for understanding what was going on is missing, so I was forced to guess at the bug. I finally got it to work by reversing the order of two terms in my formula for `health_change`, but it was a lot harder to understand what was going on when I could only guess at or simulate the values of the variables.

</comment></comment></comment><comment><USER24> Cool idea, but I don't think it makes sense for there to be both a Player class and a warrior object. They seem like they are/should be one in the same. At the very least, I think behind the scenes, the Player class should look more like this such that the warrior object is always available, and I don't need to pass it around from method to method that I define. e.g.:

        class Player
          attr_reader :warrior

          def initialize(warrior)
            @warrior = warrior
          end

          def play_turn
            # I can now access `warrior` here or in any other methods I write
          end
        end

<comment><USER25> The player object would represent the current person playing the game, i.e. you. The warrior represents the object on the screen. The player tells the warrior to take actions, so it makes sense that they're different objects.

If there were multiple warriors then your code would no longer make sense, as the control logic would have to be changing the player_instance.warrior object.

<comment><USER26> > If there were multiple warriors then your code would no longer make sense, > as the control logic would have to be changing the player_instance.warrior > object.

You need to keep previous state about warrior. E.g. delta health.

</comment></comment></comment><comment><USER27> This is awesome, glad to see I can put my ruby skills to good use playing a game!

</comment><comment><USER28> This is really great, but it would be even better if it showed where the error it's finding is located. I am getting some weird errors that I can't spot- find.

<comment><USER16> just play the original: you can use a the text editor of your choice, run in terminal, run with or without animation (nearly instant), and you have full debugging capabilities via puts. Also you get the rogue-like ascii graphics which is the original inspiration for the game.

</comment></comment><comment><USER29> Discussion from yesterday: [https://news.ycombinator.com/item?id=6110382](https://news.ycombinator.com/item?id=6110382)

</comment><comment><USER30> I really like how this manages to introduce some object-oriented principles stealthily while mostly focusing on linear logic. Great job!

</comment><comment><USER31> First couple seconds was wondering where the hell the sound was coming from, rest of the seconds were in awe. Awesome job.

</comment><comment><USER32> Oh man, I love this!

I especially loved this: "warrior.feel.empty?". Allova sudden my RubyWarrior's getting all existential!

</comment><comment><USER33> How do you tell the character to stop on a space when walking? That monster keeps killing me.

<comment><USER34>
        if warrior.feel.enemy?
          warrior.attack!
        else
          warrior.walk!
        end

</comment></comment><comment><USER4> They should also add the intermediate levels as well

[https://github.com/ryanb/ruby- warrior/tree/master/towers/int...](https://github.com/ryanb/ruby- warrior/tree/master/towers/intermediate)

</comment><comment><USER35> You should do a score based on the number of lines of code or characters you have to use.

</comment><comment><USER36> kneel down before the warrior (all levels): [https://gist.github.com/syasrebi/6097679](https://gist.github.com/syasrebi/6097679)

<comment><USER37> I aint kneeling before any warrior that shoots captives (level 8!)

</comment></comment><comment><USER38> "undefined method `elements' for [:return0]:Array"

Marvelous

<comment><USER39> don't use `return` in your functions.

</comment></comment><comment><USER40> Does anyone know more games like this? Thanks.

</comment><comment><USER41> This is a lot of fun. Well done! :)

</comment><comment><USER42> Ok, that's kind of fun :).

</comment><comment><USER40> I made it. It was great!

</comment><comment><USER43> This is very cool. I hope others copy your idea - very nice way to marry programming with games.</comment>


What is the best way to accept payments in Latin America countries? - <AUTHOR> Is a world processor like Paypal or Stripe will help me or do I need another provider? Wich one? Also, can my company receive the payments in USD or do I will need to open a bank account in those countries to receive the payments?<p>Thanks in advance! <comment><USER2> PayPal is the more mature product and is accepted in more countries. You can opt to keep funds in the native currency, or perform the cross border conversion when the payment is received.

Stripe is supported in fewer countries.

It really depends on what you realistically need.

You also need to be aware of how refunds work. Also be aware of fraud and chargebacks. You lose a lot of visibility using a third-party service with fraud detection so you either rely on their tools or rely on the 3rd party to perform the due diligence for you.

Fees are also higher to accept globally, so you need to factor that into your pricing.

[https://www.paypal.com/us/webapps/mpp/country- worldwide](https://www.paypal.com/us/webapps/mpp/country-worldwide)

[https://stripe.com/global](https://stripe.com/global)

</comment><comment><USER3> Which country are you (or your company) based on? Which countries are you selling to?</comment>


What everybody ought to know about gold and Bitcoin: Part 1: Gold as a product - <AUTHOR> https://venturegrit.substack.com/p/what-everybody-ought-to-know-about <comment><USER2> Gold is shiny and pretty and has some useful physical properties. Bitcoin has no useful properties, but some people want it anyways. Both are hoarded, and are enviromentally destructive to get.

What else do you really need to know?

<comment><USER3> Both are scarce and easy to pass on.</comment></comment>


Microsoft preps IE 8 for the web-challenged - <AUTHOR> http://www.theregister.co.uk/2008/12/04/interent_explorer_8_list/

<comment><USER2> "IE 8, currently in beta, makes it hard to view millions of existing web pages because it's the first version of Microsoft's browser that claims to be fully standards-compliant."

That is, of course, quite an ironic statement, but good for MSoft for biting the bullet and sticking with it in spite of the hurt it is going to cause.</comment>


How to explain a 3-year gap (because of health issues) on my resume (developer)? - <AUTHOR> My work experience as a software engineer goes from 2008 to 2017, and there it stops because of health issues, so it's been three years without working. Now I must get back to work. So I've just picked up my old resume in order to rewrite it, and realized I have no idea on how I'm going to explain that. On one hand it seems there's no other way besides telling the truth, but on the other hand it feels like my resume will just be ignored. Should I place it like that:
<hiatus+explanation> <job N> ... <job 2> <job 1>
Or should I write it before/after the jobs listing? Or should I just omit it? <comment><USER2> There's no perfect answer here, because different people will have different reactions to _whatever_ approach you take.

So what follows is just an opinion. I work at a large biotech company, and sometimes hire engineers. Personally, I would like to see an entry in your job list in appropriate chronological order, with a very brief explanation. Many people have to take a break, whether for raising children, caring for family, or dealing with health issues. As a hiring manager, a gap in your job history with an explanation like that is less concerning to me than a completely unexplained gap.

If you can truthfully indicate the issue is resolved and won't impact you in a future job, great; if not, just stop with the explanation of the gap.

</comment><comment><USER3> I would ommit it but be ready to explain it.

They aren't generally allowed to ask about your health to prevent discrimination. I think you could say something like "I had to take some time off to take care of a sick family member". It's technically the truth as you are a member of your family, but should prevent discrimination.

</comment><comment><USER4> if you have marketable skills. I would look into contracting. or contract to hire. a lot times you by pass HR that way.

you can be straight up with the contracting recruiter and they might even help you with what to say on your resume.

Also, they can guide you on what opportunities might be a problem and which ones won't

I opened a mortgage company a couple of years ago and got back into software development. The contracting company did care and the company eventually hired me.</comment>


The "Granny Knot" - <AUTHOR> http://www.fieggen.com/shoelace/grannyknot.htm

<comment><AUTHOR> And from the same website: [http://www.fieggen.com/shoelace/ianknot.htm](http://www.fieggen.com/shoelace/ianknot.htm) A really simple and efficient way to tie you shoelaces.

Sharing this because it's such a cool way to do such a mundane task :)</comment>


An Introduction to PLT Scheme with Pictures - <AUTHOR> http://docs.plt-scheme.org/quick/index.html <comment><USER2> i dont have the #lang slideshow module, is it supposed to come separately or only with the newest download?

<comment><USER3> Get the newest download (399).</comment></comment>


Programming language that uses photographs as source code - <AUTHOR> http://killscreendaily.com/articles/kaleidoscopic-coding-programming-language-light-pattern/

<comment><USER2> _Light Pattern works with JPEGs only, as aperture and shutter are pulled from the EXIF data._

Boo, that's cheating</comment>


China plans security offices inside Internet firms to stop 'illegal behaviour' - <AUTHOR> http://www.theguardian.com/world/2015/aug/05/china-security-offices-internet-firms-stop-illegal-behaviour

<comment><AUTHOR> Yet another example of why you simply can't trust or do any internet related business with Chinese firms. Even if these firms wanted to be above board they legally couldn't with Chinese cyber monitors breathing down your neck - literally.</comment>


Antimalarial drug linked to increased risk of death in coronavirus patients - <AUTHOR> https://www.washingtonpost.com/health/2020/05/22/hydroxychloroquine-coronavirus-study/ <comment><AUTHOR> Full title is: "Antimalarial drug touted by President Trump is linked to increased risk of death in coronavirus patients, study says"</comment>


Apple pulled Dash from the App Store for "review manipulation" - <AUTHOR> https://blog.kapeli.com/apple-removed-dash-from-the-app-store#what-happened <comment><USER2> Sounds pretty heavy-handed to ban the whole account for alleged review vote stuffing. Even if there was actual review spam going on, couldn't this be solved by just removing all existing reviews and blocking further reviews, so the app could be downloaded by searching the app store (or via a direct itunes link)? Brutal.

It also opens up a massive blackmail opportunity. Pay up or we will review- spam your app with 10000 fake 5 stars so Apple kicks you out. It's reverse xrumer all over again. Nice.

Lots of speciality and companion apps don't make any revenue from app store sales and don't care about rankings. I'm sure there's a fairly big subset of app store developers that would be happy to run their apps unlisted and possibly unreviewed, since there is no other way to deploy an ios app to the general public.

<comment><USER3> As I replied elsewhere in this thread - Bogdan is being requested by Apple to claim Apple was Correct in Banning him.

Apple found a Niece of Bogdan's for whom he bought an Apple Dev account & shared test devices, had fraud on their app review.

But Apple did not notify him they had "linked his account" to hers - and he got mysteriously banned.

I think Apple is making things worse, in this situation.

</comment></comment><comment><USER4> So what stops someone who is against X app, pays for clickworkers to leave fake reviews to get the app pulled? Would the same thing happen if fake reviews were left for a major company like Google/Microsoft/Dropbox in the app store?

</comment><comment><USER5> Freedom to install/use is one of those cases where the web beats apps, hands- down. Check out devdocs.io in your browser for a free alternative. Works just fine on mobile, too.

I love it, and after hooking it up to Alfred, I can search 90% of my commonly- needed docs with a single interface.

<comment><USER6> Doesn't devdocs.io require you to open it before going offline to work?

</comment></comment><comment><USER7> Would this be the time to explore selling iOS apps outside of the app store?

Offer users a binary download (like when you buy the desktop app outside of the store). Then have a little tool that you run on your Mac, connect the iOS device, enter your developer credentials (since this is a developer's tool the user likely has them, otherwise registration is quick and free)... and the tool sideloads the app to the iOS device.

<comment><USER8> I build what I believe is currently the most popular (mostly for being free and solid: Cydia Impactor) simple tool for this, and will point out that apps sideboards in this fashion are extremely limited as you don't have access to basic iOS functionality that requires special profiles, such as push notifications, and you can only have up to three such apps installed on an iOS 10 device at a time, each of which will have a certificate that expires after only 7 days. (Apple has been slowly clamping down on these limits; it used to be such apps expired after 30 days, then they rate limited free app identifiers to 10 per week, then they made the apps expire after 7 days, and, most recently, you are limited to 3 total installed apps.)

</comment></comment><comment><USER3> Phil Schiller accuses Kapeli of fraud:

[http://www.macrumors.com/2016/10/06/dash-pulled-for-app- stor...](http://www.macrumors.com/2016/10/06/dash-pulled-for-app-store-review- manipulation/)

"...

I hope that you understand the importance of protecting the App Store from repeated fraudulent activity.

Thank you, Phil"

<comment><USER9> I don't see anything obviously wrong in any of the Dash reviews (I think this is the correct app):

[http://webcache.googleusercontent.com/search?q=cache:1e3kQGL...](http://webcache.googleusercontent.com/search?q=cache:1e3kQGLIpDMJ:dash- api-docs.appstor.io/app-reviews+&cd=1&hl=en&ct=clnk&gl=ca)

It also seems somewhat unlikely that a developer with such great reviews would deliberately trash his competitors.

I wonder if Apple's automated fraud detection system detected it as a false positive, simply because he got so many good reviews?

<comment><USER10> Who are Dash's competitors anyway?

<comment><USER3> None AFAIK. Google search, Visual Studio / Other IDE Intellisense features.

</comment></comment></comment></comment><comment><USER11> Apple, how on earth is this good for existing customers? You're not protecting us - you're discouraging us. We've paid for the application and now can't get access to it. If there's an alternative channel, I'll never buy from an Apple app store again.

</comment><comment><USER12> Yet some how my comment got -4 points...

I can only applaud Apple for doing this

</comment><comment><USER13> He could embarrass Apple by releasing the app on Android.</comment>


Beginners view of Python/Evernote API - <AUTHOR> http://www.chucklukowski.com/2013/03/python-with-evernote-api-struggles/

<comment><AUTHOR> As you can see, I've got a long way to go. It did feel good to get this to work, though. The things I've always done with programming have been mostly tutorials.

They definitely leave you lacking as far as how to setup a program.</comment>


Justice Department memo reveals legal case for drone strikes on Americans - <AUTHOR> http://openchannel.nbcnews.com/_news/2013/02/04/16843014-exclusive-justice-department-memo-reveals-legal-case-for-drone-strikes-on-americans?lite

<comment><USER2> I wonder which whistleblower is Obama going to prosecute this time. When the government itself is the _criminal_ , then it makes perfect sense from their point of view to "eliminate" the threat, in this case the people who don't intend on becoming criminals.</comment>