Higher-order logic and equality; multiple ways to use lambda calculus for logic - <AUTHOR> https://blog.burakemir.ch/2020/04/higher-order-logic-and-equality.html <comment><USER2> In a world where cranks use Curry-Howard to justify their ridiculous beliefs, it is refreshing to see not just a correct application, but a well-formed and aesthetically pleasing presentation. Thank you for not trying to obfuscate the material.

<comment><USER3> > where cranks use Curry-Howard to justify their ridiculous beliefs

I'm not an abstract thinker so that correspondence is not interesting to me (open to being educated though if it is applicable to my daily work), but to what ridiculous beliefs do you refer? TIA

<comment><USER2> Curry-Howard-Lambek distills largely into a big table which relates type theory, category theory, formal logic, and metamathematics. This table is very precise, but high-dimensional, so that we can only take small limited slices of it. Nonetheless, the slices that we take are very formal. The important parts are well-known and published, say at [0] or [1]; extending beyond this is possible but requires care and effort. That said, once one groks the nature of the correspondence, then it becomes painfully obvious, to the point where folks who don't grok it seem block-headed.

I don't really have a glossary or nosology of how people misuse this, but I'd say some wrong ideas include:

* If a language has a type system, then it is usable for formal proofs, it is sound, and it is a language that ends the need for other languages.

* Dependently-typed languages have values that are also types, so all values are types, and therefore dependent typing makes no sense.

* Because my language uses higher-order logic instead of first-order logic, Turing's results don't limit my language's problem-solving abilities.

* Because of my religious beliefs, type universes have a certain shape, and thus Cantor's results are incorrect.

* The English language is far more powerful than any programming language.

* All logic is really just intuitionistic logic.

* All logic is really just linear logic.

* Syntactic formalism must be wrong, because abstracta only exist in my mind.

To repeat myself, all of these are _wrong_ , despite some relatively large tribes of programmers believing them sincerely.

[0] [https://ncatlab.org/nlab/show/relation+between+type+theory+a...](https://ncatlab.org/nlab/show/relation+between+type+theory+and+category+theory)

[1] [http://math.ucr.edu/home/baez/rosetta.pdf](http://math.ucr.edu/home/baez/rosetta.pdf)

<comment><USER4> Thank you! That list intersects with some of what has been troubling me too. You should write a blog post or paper expanding on these. Some of these beliefs are more dangerous than others. Especially:

> * All logic is really just linear logic.

and

> * Because of my religious beliefs, type universes have a certain shape, and > thus Cantor's results are incorrect.

</comment></comment></comment></comment><comment><USER5> IMO Paul Tarau has some good stuff in this area, e.g.: "On a uniform representation of combinators, arithmetic, lambda terms and types", Paul Tarau [https://dl.acm.org/doi/10.1145/2790449.2790526](https://dl.acm.org/doi/10.1145/2790449.2790526)

Abstract:

> A uniform representation, as binary trees with empty leaves, is given to > expressions built with Rosser's X-combinator, natural numbers, lambda terms > and simple types. Type inference, normalization of combinator expressions > and lambda terms in de Bruijn notation, ranking/unranking algorithms and > tree-based natural numbers are described as a literate Prolog program.

> With sound unification and compact expression of combinatorial generation > algorithms, logic programming is shown to conveniently host a declarative > playground where interesting properties and behaviors emerge from the > interaction of heterogenous but deeply connected computational objects.

</comment><comment><USER6> > Yet, I believe it is fairly common to call this kind of logic intuitionistic > logic, even though there is no rule for ⊥.

I don't believe this is very common—it's _an_ intuitionist logic, but "intuitionistic logic" by itself pretty much always includes ex falso—but actually it's rather strange that this is the case; it's not immediately clear that ex falso is constructive at all!

Minimal logic is both 'intuitionistic' (since LEM does not hold) and paraconsistent (since ex falso does not hold). I actually think there's a fairly solid case to say that only paraconsistent logics can be thought of as truly constructive; certainly if we start from BHK, it's not at all obvious that ex falso is a sound principle, and Kolmogorov himself had great issues accepting this. When he finally managed to convince himself of this in 1932 [1], it seems more that he was trying to finish off the logical framework by sidestepping the issue.

Kapsner [2] argues that the constructivist can only accept ex falso if she is willing to accept so called "empty promise constructions" as being constructive (see the source for more details on what this means, but it seems to broadly line up with Kolmogorov's justification); I personally don't think that they are compatible with the way BHK is usually presented at all.

Brouwer isn't around to tell us exactly what _he_ means by constructivism, so ultimately this is all philosophical, but I think this it's an interesting area that people don't really think aboutl I think a lot of people are exposed to intuitionistic logic via Martin-Lof type theories but don't actually consider how the logic fits into the wider notion of constructivism.

[1] : [https://plato.stanford.edu/entries/intuitionistic-logic- deve...](https://plato.stanford.edu/entries/intuitionistic-logic- development/#Kolm1932Heyt1934)

[2] : [https://www.springer.com/gp/book/9783319052052](https://www.springer.com/gp/book/9783319052052)

</comment><comment> ibn-python During undergrad, I was only exposed to logic in my set theory and theory of computation classes. Any recommendations on good books/textbooks that are good for a relative beginners exploring set theory and type theory?

<comment><USER7> This is a list of type theory resources: [https://github.com/jozefg/learn- tt](https://github.com/jozefg/learn-tt)

This is an exposition of Martin-Lof's dependent type theory: [http://www.cs.nott.ac.uk/~psztxa/mgs-17/notes- mgs17.pdf](http://www.cs.nott.ac.uk/~psztxa/mgs-17/notes-mgs17.pdf) Section 5 is about Homotopy Type Theory (HoTT), a newer type theory that is still being developed.

Chapter 1 of the HoTT book introduces Martin-Lof's dependent type theory, then the rest of the book covers HoTT-specific topics: [https://homotopytypetheory.org/book/](https://homotopytypetheory.org/book/)

</comment></comment><comment> alan-crowe These are ideas are implemented in the theorem prover HOL light [https://www.cl.cam.ac.uk/~jrh13/hol- light/](https://www.cl.cam.ac.uk/~jrh13/hol-light/)

I find the discussion in of logic in [https://sites.math.northwestern.edu/~richter/HolInformalMath...](https://sites.math.northwestern.edu/~richter/HolInformalMath.pdf) more concrete and more accessible.

</comment><comment><USER8> I put a related question on Computer Science Stack Exchange a week ago. Linking it here in the hopes that HN users roll-calling here will shed some light.

Ref: [https://cs.stackexchange.com/questions/122066/does-the- under...](https://cs.stackexchange.com/questions/122066/does-the-underlying- computational-calculus-in-type-theories-affect-decidability)

</comment><comment><USER9> Struggling to get past the Minimal Logic section as I don't recognise the notation. Any pointers?

<comment><USER10> The term you want to search for is "Natural Deduction". It's what you use if you study type theory. I don't know any lightweight introductions off the top of my head.

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

The short version is that

        A     B
        </comment></comment><comment>-
           C

means "If A and B, then C". Any free variables in A, B, C are universally quantified outside the "if". The reason for writing the rules in this weird format is that you can combine them in a tree:

        A     B
        </comment><comment>-
           C       D
           </comment><comment>---
               E

This proves E, given A, B, and D, via the application of two rules.

<comment><USER11> The blog post (and your response) is actually a bit confusing, as we should be seeing inline rules -- at least that's how I've seen it in just about every textbook. The "implication" rule you suggest is actually (technically) called "elimination" (in λ-calculus, we say you _eliminate a variable_ ) and should be denoted via _→e_ (sometimes the arrow is omitted). As a more practical example, see proposition (11) in this paper I wrote back in college[1]. There are two elimination rules, both denoted by an inline _→e_.

[1] [https://dvt.name/logic/horse2.pdf](https://dvt.name/logic/horse2.pdf)

<comment><USER12> While naming the different derivation rules can be useful for guiding readers the names are not formally necessary.

The rules

      A   B
      -----
        C

and

      A   B
      ----- (→c)
        C

are logically equivalent, the latter just gives you a name to refer to the rule by.

Additionally, I would be careful about correcting others that something is "technically" called something else as programming language researchers often use many names for the same concept.

<comment><USER11> > Additionally, I would be careful about correcting others that something is > "technically" called something else as programming language researchers > often use many names for the same concept.

My point had nothing to do with programming language research (in fact, my academic background is logic/metalogic). And by the way, this is _not_ a rule:

        A   B
        ----- (→c)
          C

It's a _derivation_ (also known as a _proof_ ) -- technical terms are important when doing logic. The rule is →c -- so I know what you're doing by including the →c there. Why the →c is necessary (and, again, I've seen it in every lambda calculus/type theory book I've taken a gander at) is because there are many rules[1] (including _several_ kinds of elimination, so things can get complicated and it's important to keep our ducks in a row).

[1] [https://www.irif.fr/~mellies/mpri/mpri- ens/biblio/Selinger-L...](https://www.irif.fr/~mellies/mpri/mpri- ens/biblio/Selinger-Lambda-Calculus-Notes.pdf)

<comment><USER12> Perhaps using abstract names A, B, and C was unclear. The following is the rule that is commonly referred to as modus ponens:

      A → B    A
      </comment></comment></comment></comment></comment><comment>-----
           B

However, modus ponens is just one of the names for this. I could also call it function elimination. I could call it →e. Or I could not bother giving it a name and just say that this is a rule in my logic call it whatever you want in your head if you so desire.

Things _can_ get complicated, but they aren't always complicated so naming rules isn't strictly necessary.</comment>


Ask HN: Backing up online services? - <AUTHOR>

I'd like to backup my Asana to my Evernote.<p>I know that IFTTT and Zapier have things where I can create a new Evernote note if I create a new task on Asana and stuff like that, but is there anything that does specifically backups of online services and keeps them synced? <comment><USER2> Zapier co-founder here, we've heard this question a lot and TBH, it is a fairly difficult thing to do. In addition to lots of users using Zapier to dump important data into Google Spreadsheets for safe keeping, I've heard of users having success with [https://www.backupify.com/](https://www.backupify.com/).

Good luck!</comment>


Facebook, Google, Apple and Amazon haven't joined the new anti-travel ban brief - <AUTHOR> http://www.recode.net/2017/3/16/14948732/facebook-apple-google-amazon-travel-ban-trump <comment><USER2> Because it's no longer beneficial for them to do so.

The main news cycle window is over, the shock effect has passed, news outlets don't run stories 24/7 about some poor millennial with an unfortunate skin complexion stuck at an airport.

Nothing to gain from a PR standpoint and everything to lose from a political one with the current administration.

Neither of these companies really makes decisions based on morality they do it based on calculated risks and benefits.

They need to administration to ease on h1b restrictions and don't make it harder for them to store money offshore and use it as a credit line without officially repatriating it.

So standing up for one kind of brown people takes a back seat so they can import another kind.

Note: if you have problem with the language of this comment google ad absurdum.

</comment><comment><USER3> Could it not just be that it's redundant for them to sign on the second brief? Opposing the first ban is obviously opposing the second. I don't think it needs to be some conspiracy about corporate politics and PR.

</comment><comment><USER4> Strange. Is political pressure out of the question?</comment>


Gnu tar happily connects to remote hosts, depending on filename - <AUTHOR>

Today I Learned:

    $ tar xvzf wtf:foo.tar
    tar (child): Cannot connect to wtf: resolve failed
 Apparently the ":" in the filename tells tar to connect to "wtf" using the "rsh" command (aliased to "ssh").
There is no mention of this in the man page: http://linuxcommand.org/lc3_man_pages/tar1.html ; apart from the rather surprising --rsh-command and --rmt-command options.
This actually is documented in the "info" pages:
http://www.gnu.org/software/tar/manual/tar.html#SEC152 :

    '-f [hostname:]file'
    '--file=[hostname:]file'

        Use archive file or device file on hostname.

    If the file name contains a ':', it is interpreted as 'hostname:file
    name'. If the hostname contains an at sign ('@'), it is treated as
    'user@hostname:file name'. In either case, tar will invoke the command
    rsh (or remsh) to start up an /usr/libexec/rmt on the remote machine
 Isn't it dangerous that a random filename could trigger "tar" to connect to remote hosts ? <comment><USER2> It doesn't look particularly dangerous, but it could be irritating if your filename has a colon character in it. Still, I never heard of this usage of tar before, and I routinely manage several score linux servers. Pretty surprising.

</comment><comment><USER3> In what way? I mean to say that I could probably think of something, but do you have some specific danger in mind?

<comment><USER4> The colon's a legal character in Unix filenames, so it's possible someone could send you a file named somehostname:foo.tar and convince you to run tar on it. Of course, if you quote the filename or escape the \:, as bash autocompletion would do, it wouldn't be an issue, but I could imagine some possible scenario.

<comment><USER5> I don't see how quoting or a shell-level backslash would change tar's behavior to something safe. Tar would still see a colon in its argv either way. Right?

<comment><USER6> No, it would see \:</comment></comment></comment></comment>


You think you know what teachers do. Right? Wrong. - <AUTHOR> http://www.washingtonpost.com/blogs/answer-sheet/wp/2014/02/22/you-think-you-know-what-teachers-do-right-wrong/ <comment><USER2> This is true of being a professor as well (I certainly didn't understand what teaching really was about until I starting doing it).

I've always thought that our graduate students should be made to take acting lessons, because there's an element of second-order persuasion you have to do in a classroom that's hard to learn and difficult to describe but that shares some similarity to acting -- or maybe just rhetoric in the very ancient sense.

You can't just purvey information and mumble something about its importance. Ultimately, you're modeling what it means to be an intellectual -- trying to give your students certain habits of mind by showing them how those habits play out in practice.

We also spend an enormous amount of time trying to devise strategies for dealing with students who just don't get it (and you quickly learn -- or better learn -- that this might be the most important part of the job).

I could say more, of course. It's a very subtle set of skills -- more art than science, as they say. It's hard to do it at the college level, and I think it's far, far harder to do it at the elementary level, where the stakes are much higher.

<comment> barry-cotter What kind of third level institution do you work at? One is under the impress that going from passable to outstanding in teaching has much, much less effect on one's chances of getting tenure than going from mediocre to good in your research.

<comment><USER3> They never said it was particularly important for career advancement. How did you read that into their post?

Also, what's with the condescending sneery tone?

<comment><USER4> Because every time a post on education comes on HN everyone thinks they know all the answers. The comments end up turning into a "Well this is the real reason..." or "Everyone needs to be just like..."

The discussions end up being so worthless that I now flag every education related post on HN because it's just not worth the time here.

<comment><USER5> Why do you think it's called master of Arts in teaching, and not master of Science?

</comment></comment></comment></comment></comment><comment><USER6> My wife is a teacher. I am consistently shocked how much work she does in evenings, weekends. I earn more than twice as much as her and more than her maximum salary cap (we are both early in our careers). She blows me away in her dedication and effort, it's a great inspiration for me to continually study and work harder.

I mention it to people and always hear 'well maybe she is different but I've seen lots of teachers and they just do it for the holiday'. As if everyone is equally dedicated in any profession. As if the guy that sits at his computer 'working' for hours a day is a more efficient or effective worker just because he does more hours. As if outside observers of any industry can really spot who is producing vs who is not.

<comment><USER7> I can echo your story exactly. My wife teaches and is involved in an after school program. It isn't football but has a similar time commitment. During certain parts of the year she works 6 days a week often leaving the house at 8 am and returning at 9 or 10 pm. It is insane. Two other teachers in her department work similar hours. The pay per hour isn't very good once you factor all of that in.

<comment><USER8> At the other end of the spectrum, one of the teachers at my old school used to turn up at 8:30 and leave at 15:30. She used to put a video on, and then hand out worksheets to fill in whilst she marked the worksheets from the class before. Terrible teacher, luckily I only had her for a few weeks.

<comment><USER9> I have a few friends that are teachers and most of their schools wouldn't allow for this sort of thing to happen. Teachers aren't allowed to sit at their desk while a class is in session, they must be instructing or walking around (during a test, video, etc...). They get a planning period, where they might have a chance to do some grading or lesson planning, if they don't need to meet with a parent or something. This means they need to either stick around school several hours after it lets out to grade work and do lesson plans, or bring it home and work on it that night.

</comment></comment></comment></comment><comment><USER10> >The problem with teaching as a profession is that every single adult citizen of this country thinks that they know what teachers do. And they don't. So they prescribe solutions, and they develop public policy, and they editorialize, and they politicize. And they don't listen to those who do know. Those who could teach. The teachers.

Sorry, I cant take this seriously. The teachers unions are one of the most politically powerful entities in the US. They can make a candidate, and they can break a candidate. They can pass and tank ballot measures...even ones completely unrelated to their jobs. They can protect drunkards and criminals from getting prosecuted, let alone fired. They are fine forcing their agenda down our throats, but they cant take a little pushback?

<comment><USER11> > _They are fine forcing their agenda down our throats_ //

The agenda of ensuring children have access to life-enhancing educational opportunities?

> _They can make a candidate, and they can break a candidate._ //

You mean a political candidate? You really think that the combined voice of a group of teachers can do that against the weight of media conglomerates, other unions, rich lobbyists and other political groups? Any examples?

Presumably under your assertion the education system in the USA is the one that the teaching unions have won by political action and the politicos and business people are looking on powerless to influence it?

<comment><USER12> Well, I can say that in two weeks of homeschooling I got my son to write more than they did in five years.

He was having trouble with bullies and the school did nothing about it. They pretty much gave up on teaching spelling completely. We found out that our school is a "magnet school" for behaviorally disturbed "special" kids from other districts so kids in the rich school and kids in the poor school where communities complain a lot get to enjoy a safer environment because the rural school gets all the psychotic kids.

I gave up on them when the superintendent gave a "town hall" where he told the mother of a "special" kid that he was a partner in his education and he told me I should just butt out because he was the expert and there's a new paradigm and homework is obsolete and because I don't have a phone number to call to get Albany breathing down his neck.

F the teacher's unions.

<comment><USER13> The problems you experienced go beyond teachers unions. Dumping "problem" kids into one school is a recipe for disaster and communities are not served by that kind of thing at all (except those that dumped off students, although I would argue those communities aren't fixing their underlying problems). Administrator heavy, top down approaches that override community and teacher autonomy are a bad thing in general, and the obsession with testing over standard lessons and homework is a huge problem with the way the public education system is run.

Ultimately teachers as a professional class deserve a union. We see in other places and countries that the unions do not serve as an impediment to a quality public education, so we have to ask ourselves what is really going on with current systems and unions that make the situation so shitty (esp. in New York state).

<comment><USER12> I'm not saying that teachers shouldn't have a union, but from my perspective it is part of the problem rather than the solution more often than not.

For instance, they opened a charter school in our district which seems to be an honest effort to provide a safe (bullying free) environment for the high school and there have been two people associated with the union who have just been consistently hateful trying to shut it down.

<comment><USER13> The charter school movement is one of those things that draws strong opinions. Initiatives to provide safe school environments are good, but privatized charter schools have a lot of downside in terms of how a community, parents, and teachers can retain control over how education happens. In New York state in particular, there has been a strong effort to close public schools and open private charters, which in my opinion is the wrong way to fix problems with public education. The disagreement over charters isn't just a union thing, although public educators would be upset to see the system they work for dismantled instead of repaired.

</comment></comment></comment></comment></comment></comment><comment><USER14> puff piece, if not pure propaganda bordering on hyperbole.

People and students respect teachers as a whole, what they do not respect and I bet many in the profession do as well is the inability to remove those who are not good teachers.

It is not a position one walks into without many upon many stories about what your really getting into. My Aunt retired from the trade, her aggravations in order that I remember are, Administrative people(usually political appointees), other teachers, and parents. There were a few others but mostly the tripe coming down from non teachers within the system seemed to be what we heard of.

That and the personal money she spent to have supplies because it was more important to blow money on marble floors than supplied, or having someone's wife/kid/friend in some advisement position that did nothing but occupy space.

Guess what, I can say the same of some other service professions, having a neighbor who does night shifts as a nurse and hearing the horror stories of what she puts up with is enough to let me know some jobs come with extra mental if not physical stress.

I think in the end we are all more than willing to heap accolades on good teachers. Its a system where the kids aren't first that irritates

</comment><comment><USER15> Teacher worship can only go so far.

Because this post makes the claim that _all_ teachers should be looked up to.

My entire family consists of teachers. They know who the bad teachers are. You've got Paulina Pensioner who just shows old VHS tapes as a history cirriculum. Or Carl the Coach that knows, just _knows_ there's only one way to solve this pre-algebra problem.

And some teachers work hard. They bust their ass and bring grading home and lesson plan on the weekends.

But they aren't the problem. There's a bad system that keeps bad teachers in at the expense of the good.

So they design tests and standards as a way to "firewall" these bad teachers in, to turn their poor performance into mediocre performance. And there's a cost, because it removes the creativity and initiative from the good teachers.

I understand that the goal of the author is to criticize common core, but while the conclusion is sound (Core is garbage) the reasoning is not.

And the new standards being developed? One of the main proponents is the Council of Chief State School officers. Many (probably most) came from the teaching profession. Who know what it's like to be a teacher.

The author gives us some feel-good patronization about how teachers have it so hard and we have no right to impose standards upon them. But these standards exist because we can't fire bad teachers.

<comment><USER16> I don't think Core is garbage at all. I think there's a deeply ingrained culture of anti-intellectualism in US culture that needs to be nuked out of the school system, and I honestly couldn't care less what the collateral damage is.

<comment><USER15> Here's the thing.

You like it when there's wide, sweeping cirriculum on the Federal level... when you agree with it.

But what happens if there's enough political pressure (it is a midterm election cycle) to add ID into the cirriculum? Or maybe they look at feel-good math that is just teaching to the test [1]?

And that's the issue. Centralized power is great when you agree with it, but terrible in the wrong hands.

[1] [http://www.momdot.com/common-core-is-making-me- stupider/](http://www.momdot.com/common-core-is-making-me-stupider/)

<comment><USER16> I agree with your point. I suppose I'm fortunate enough to also agree with the goals of Common Core as they are today.

Onto that article, however:

1\. I never use an academic degree as an indicator of intellectual capacity. I find that some people are so objective-driven that they zoom right past the point and straight to rageville when they don't understand something.

2\. A simple Google search on front-end estimation would have helped this mom realize that the example given on the sheet is incorrect. I will concede that an effective teacher would have realized that the example given is incorrect and would have corrected it.

(In front end estimation, you round the leftmost digit, so the example should actually be 400 + 300, not 300 + 200). IMHO 700 is actually a decent estimate for 645, so I don't think there's a problem with the math itself. It's not really feel-good math, but I think some people take for granted that estimation is not an innate ability.

Now, it becomes another discussion altogether when the teacher is so horrible that they refuse to accept that the example is wrong. But, I don't think I've seen evidence of that, so I won't accuse anyone of anything.

EDIT: I just read some of the comments in that article, and it looks like some districts teach front-end estimation with truncation rather than rounding, in which case 300 + 200 = 500 would be correct.

Here are a few more things to note: the parents here _assume_ that estimation and rounding are the same thing. That in itself isn't true.

More importantly, though, look at the _goal_ of the estimation -- to see if the _actual_ answer, 645, is reasonable. That's _not_ the same thing as asking if 500 is a reasonable estimate of 645. I think the point of this exercise is for kids to say "ok, if I add these two numbers together, I _expect_ to get a 3-digit number somewhere in the ballpark of 500." That is to say: if I add 354 and 291, I shouldn't expect to get 20000 or 7 or 81 or 9750. It's just a simple way of checking your work using a quick, easy method that you can do in your head. Again, I find the value in this -- adding "common sense" to the curriculum is definitely something I can get behind, but I understand that parents who aren't used to "common sense on paper" will struggle.

</comment></comment></comment></comment><comment><USER17> I hate writing like this. Even if most people don't know the thing you're referring to, basically telling the entire browsing population of the internet "we're all stupid and here's why" immediately leaves a bad taste, particularly for people -- you know, like _teachers_ \-- who _do_ know what teachers do, or people who didn't make the assumption being assumed in the first place (which says a lot more about the author than anything else).

Pedantic? Maybe. But to me this is a really childish way to make a point that could be better stated in a way that doesn't instantly, baselessly denigrate the reader, particularly when you're writing for a publication that banks on its credibility and reputation.

</comment><comment><USER18> I have tons of respect and sympathy for teachers, but the argument I often hear for raising their pay ("they work really hard, they're super important, it's a difficult job") misses the central point.

It seems like we have enough teachers at the wages we currently pay. Teachers are willing to go into the profession despite the low wages, probably because they want a satisfying job with good benefits. If we didn't have enough teachers...we'd have to raise wages. Supply and demand.

<comment><USER19> And like many other situations which can be summed up as supply and demand, a race to the bottom is an obvious outcome.

Maybe we'd get better teachers if we paid more?

<comment><USER18> We'd get better teachers if we paid more to good teachers. The problem is no one can seem to agree on how to measure what makes a good teacher - one side is busy arguing seniority should be the primary measure, the other side argues test scores, and neither one seems to want to spend any time or money figuring out an actually successful way to measure teacher skill.

<comment><USER20> You could _ask the kids_. They certainly know which classes are engaging, and which are time-biding garbage. And ultimately, assuming a teacher isn't running a movie theatre, student interest _is_ the most important metric. You'd of course have to keep the actual weighting process a bit fluid to avoid the inmates gaining control of the asylum, but it should be quite straightforward to pick out the extreme bad and extreme good teachers.

It would also be a good introduction to the rationale behind secret ballots, and when it is actually appropriate to lie.

<comment><USER21> Look at ratemyprofessor and see how well an incredibly difficult professor that is also engaging and interesting does; now imagine that in a situation where the people in his/her class are forced to be there.

<comment><USER20> I took a quick look through that site, paging through my alma mater of a decade ago. I do see pathologies in the ratings/comments that remind me of complaints I would hear about professors from fellow students that were stressed, not getting the material, or used to a more structured environment. And if these ratings held weight with the university, I can definitely see professors dumbing down their lessons to avoid bad reviews. So I do see what you're getting at with it going terribly wrong.

Still, I think there's several key differences:

1\. Every school student would be rating their teachers, rather than just those that loved a professor, had an axe to grind, or were encouraged to by an entertaining personality.

2\. The context would be "closed", with each teacher relative to their school, rather than open cross-institution competition with a front page of featured "rockstar" professors that make the rest seem inadequate.

3\. The high schools officially sanctioning ratings with real results would give kids the feeling that they really do have a stake in the process, rather than simply being its victims.

4\. High school is a more structured environment where the process details matter a lot more. So a teacher eg giving out an incomplete homework problem is actually a valid indictment rather than the stressed out nitpicking of a culture shocked freshman.

5\. In college, there's a certain level of appreciation for the material that everyone should have but doesn't necessarily, causing them to get frustrated at a professor with a dry personality. Whereas with high school, the idea is that everybody should be learning a cursory understanding of all subjects.

6\. In college, there's a huge variation in the level of courses. One specific professor I had for a seminar where it was basically his PhD research group and me, an undergrad who'd just started on a simultaneous master's. I learned _a lot_ in that class, and really appreciated him. I then ended up in a grad- level "intro" course with him (which I knew was an utter waste going in, but it was the only thing that fit my schedule). Most of the students were rote- memorization paying-for-credential types, but his style certainly did them no favors either, and I can definitely see my recollection echoed in a few of his current reviews. I'd say that he's still a teaching asset, but not for intro lectures where most students aren't already committed to the subject.

Really, there just needs to be _some_ extrinsic motivation/reward for teachers that are truly making a difference versus simply clock-punching, and that's not more top-down testing edicts that further shackle them. And sure, the immediate reaction shouldn't be to fire the lowest-reviewed, but neither should we pretend that they deserve similar compensation to the exceptional ones.

</comment></comment></comment></comment></comment></comment><comment><USER22> You think you know what field workers do. Right? Wrong.

You think you know what factory workers do. Right? Wrong.

You think you know what farmers do. Right? Wrong.

You think you know what oil rig operators do. Right? Wrong.

You think you know what coffee shop owners do. Right? Wrong.

You think you know what lawn care specialists do. Right? Wrong.

<comment><USER23> I agree with your point: the title is sensationalist. The difference between teaching and owning a coffee shop (and the others examples) is that few people will try to tell you how to handle your coffee shop while a lot think they know better than you how their children should be taught.

<comment><USER22> I've seen a close friend work 20 hours a day, barely make payroll, deal with employee drug habits and try to minimize the legal damage a sociopathic employee did.

You don't know what it's like owning a coffee shop.

</comment></comment></comment><comment><USER24> In other words, teachers are human and have real lives. This may be news to an 18-year-old, but I'd really be surprised if it's really news to that many people above 30. I may not be a teacher but I could fill a very stylistically- similar paragraph or two with the woes that have befallen me, too. Most people can.

This strikes me as a variant on the _You don 't know what's like!_ meme... as a rule of thumb, you should _never_ say that to anybody. You have no idea what they've been through. Everyone you pass on the street has a story, and no matter how bad you think yours is, you've got no guarantee that they don't have one worse than you.

What this essay describes is not specially "teaching", it's _life_.

<comment><USER6> You as an individual and your profession as a whole are different.

There is a very pertinent and legitimate point made in the article that -teaching- is not a respected industry.

It's not exactly a new comment!

<comment><USER25> Come to think of it, I don't think I hear teaching described as an industry very often.

What would be different if teaching were considered an industry? Would it be better?

</comment></comment></comment><comment><USER26> Teaching falls into the same category as stage magic, stand-up comedy and writing - it looks easy and effortless when done by an expert because that's part of the expertise. Capturing attention, exciting young minds and engaging them is something that, when done effectively, is transparent because that's how it works best. The whole host of knock-on problems that are spawned by this apparent ease are well-documented in TFA.

</comment><comment><USER27> i see a lot of comments saying that we're watching from the sidelines criticizing, and therefore have no clue what's going on.

How is that even remotely true? We are the victims of the system. We experience firsthand what they do or believe they do.

This is like saying you think you know what the TSA is doing. Right? Wrong. Of course we do, we're the ones being screened.

what we don't know is the logic and culture behind the decisions we see, but that doesn't take any right away to criticize it.

having been an overachiever in school, and early university, it's been a constant struggle. "oh but school is not actually made for people like you" you say. yeah, i know. how is that not a problem?

edit: don't get me wrong, i've had a few really good teachers. but they've been rather few. and no, i'm not just counting the teachers i liked as good.

<comment><USER28> Does someone who's used a computer all their life know the ins and outs of being a programmer? Would you listen to their recommendations on how to improve your code? The answer is likely yes, feedback from customers is important - but you're not gonna get any useful advice re: the architecture or the design patterns used.

</comment></comment><comment><USER29> Awhile ago, I had a teacher for a roommmate, and one who was young and very passionate, and I hope, good at it, because we were best friends and I'd hate to think I'd be a poor judge :). But I rarely heard her talk about the pure joy of teaching, at least compared to the difficulties of dealing with the management (the principal) and other logistics issues...such as having to pay for her own classroom supplies, including books that she wanted if they weren't on the state-wide curriculum, and pencil and paper for her poorer students.

Her complaints about office politics were what really surprised me. Even though I know every bureaucracy is universally crushing (well, maybe I grok better now after watching The Wire), it just seems that being a great, passionate teacher, supersedes any kind of office bullshit...such as the way principal communicates with you. But then again, if you can't get along with the person who runs the place, and you're put in a shitty classroom and have to share a teacher's officespace with 3 other novices...how could that _not_ affect your teaching performance and job satisfaction?

One memory I still have from high school was one afternoon when I had to stay after school to give a presentation to the teachers on their regular Thursday- school-wide meeting. The meeting was in the cafeteria...and you know how lunch tables reflect a sort of social-hierarchy among kids? It was no different for the teachers...and even more surprising, the social lines seemed to fall along with how I, as a student, expected them to (attractive young teachers sat with the other young teachers; cool popular teachers could sit anywhere they want; the weird chemistry teacher sat in the corner). I mean, it's one thing to have perceptions as a kid, but I _knew_ I was a petty kid...so it was a surprise to see that things were not much different in the adult world.

<comment><USER30> Grok means to understand in fullness ... from the Heinlein novel, the etymology of the word comes from to drink or to consume.

You cannot grok something just by watching it.

<comment><USER29> Yeah, but we're talking about _The Wire_ here :). But also I was an education reporter, worked as an aide, and have been part of other bureaucracies myself...

</comment></comment></comment><comment><USER31> >Most of all, we need to stop thinking that we know anything about teaching merely by virtue of having once been students.

I know something about teaching by reading peer-reviewed studies which give evidence for better teaching methods, but are almost never adopted because the teaching systems and/or teachers are extremely conservative apparently all around the world.

In fact, I'd trust studies over teachers any day.

</comment><comment><USER32> I feel like you could write this about basically any profession, besides the usual "teachers are underpaid" rant.

</comment><comment><USER25>
        > All of you former students: you did not design
        > curricula, plan lessons, attend faculty meetings,
        > assess papers, design rubrics, create exams, prepare
        > report cards, and monitor attendance. You did
        > not tutor students, review rough drafts, and create
        > study questions. You did not assign homework. You
        > did not write daily lesson objectives on the
        > white board. You did not write poems of the week
        > on the white board. You did not write homework on
        > the white board. You did not learn to write
        > legibly on the white board while simultaneously
        > making sure that none of your students threw a
        > chair out a window.

I'm not a teacher, so I could be wrong, but it seems to me that much of this list falls into two categories:

1\. Routine things that could be orders of magnitude more efficient (or even fully automated) given enough resources. In most cases, the resources needed would be fairly modest compared to the aggregate amount of effort teachers everywhere spend on them. Writing and grading elementary-level math tests, for example, shouldn't take any time at all given the right software.

2\. Routine things that couldn't be automated well but could easily be done by some sort of entry-level assistant. Babysitting and discipline tasks don't require college degrees.

It strikes me that the economics of education are structured in a way that there is marginal impetus to improve efficiencies in the day-to-day work of teachers.

<comment><USER33> You are not a teacher. And from your comments, you have not looked too much in the research about how to teach students.

Yes, certain things COULD be automated... at considerable expense to student achievement. One big thing they have found - remove the personal feedback and connection to students --> lose the motivation of students. If a teacher (the same teacher) isn't interacting with a student consistently at nearly every step of the learning process, the feedback doesn't stick and the student loses motivation.

It would be interesting to looking to the basic research behind the feedback- achievement connection and stereotype threat to start.

Hope that helps you address some of the problems with the automate/delegate solutions so often thrown at teachers.

<comment><USER25> > Yes, certain things COULD be automated... at considerable expense to student > achievement.

I seriously doubt that letting teachers automatically grade arithmetic tests will hurt student achievement. The fact is that many teachers do that sort of thing at home in what should be considered overtime hours. I would like to hear how automatic grading causes student achievement to suffer.

Likewise, I'm skeptical that it should be solely educators' responsibility to make sure chairs are not being thrown out windows. Letting teachers focus on educating and not babysitting seems like a good thing.

</comment></comment></comment><comment><USER34> I did two years of a special ed major in college before switching over to computer science and I can say that the ed program I was in covered in depth how to teach and handle a class room, it focused on how to teach math to people who don't understand any concepts, and the department had additional offered classes if you wanted to do teach for america or inner city schooling.

Speaking with friends who have become professors they are often jealous of this because they were never given any kind of 'teaching' classes. Their under grad wasn't in education and their teaching experience was trial by fire teaching assistant jobs of handling undergrad college courses.

All that said, I grow tired of the arguments and articles of 'don't speak unless you've walked a thousand miles' which I felt as I read this article. Not all knowledge and understanding must derive from doing something to have a valid opinion. We need to treat teachers better and find better pay structures but I've found no harsher critics of teachers and our schools than the teachers I went to college with as they filter into the systems and find tired and broken systems in which they get no voice until they have 'tenure'.

<comment><USER33> > All that said, I grow tired of the arguments and articles > of 'don't speak > unless you've walked a thousand miles' > which I felt as I read this > article. Not all knowledge and > understanding must derive from doing > something to have a > valid opinion. We need to treat teachers better and > find > better pay structures but I've found no harsher critics of > teachers > and our schools than the teachers I went to > college with as they filter > into the systems and find > tired and broken systems in which they get no > voice until > they have 'tenure'.

I don't know that this article is so much about "not speaking bad about teachers", but about having compassion for teachers and talking about education with a little more humility for the institution that helped produce you. I would say this article is more of the "teachers don't write articles about how to __________ better, so don't let _______________ers tell teachers how to teach better" variety.

And I totally agree that most young teachers are completely overwhelmed by the ridiculous systems in which they are forced to teach. My only hope is that some of these young, inspiring teachers remain in the profession long enough to change the broken system (which might take a LONG time!). The unions are broken; for the most part, teachers are not.

</comment></comment><comment><USER35> I'm not sure what the implication at the end is about public policy? Even if we supposedly do not understand teaching, that does not mean we can't form opinions about the current system and develop policies for it. That's precisely how politics work in every other field.

How many people who want to ban fracking actually understand fracking or precisely what the real risks are? How many people want to ban nuclear energy and don't understand any of the actual risks of modern nuclear power plants?

Politics suck for anyone that isn't a politician. Each industry must learn how to deal with that aspect. Writing an appeal to emotion on the Washington Post is not going to sway anyone. It just resonates with people already on their side and sounds like whining to people that aren't.

</comment><comment><USER36> Since the author says she started out making 5 times as much as a lawyer than as a teacher, I can only assume she landed one of the associate jobs at a major law firm straight out of law school making $160k+.

She makes it sound like anybody can hit up law school and come out making almost $200k. The vast majority of law graduates do not land jobs like that. The vast majority also have nearly crippling debt. The vast majority of the firms paying $160k+ are also in hyper expensive metro areas, whereas teachers can live comfortable lives in very rural towns (if they want to).

<comment><USER9> While what she is stating might not be the case for all law school grads, it isn't as far fetched to come out of school easily making 2-3 times what a starting teacher is making, depepnding on the degree you choose. As a software engineer in michigan, you can come out of uni with a BS in computer science and easily find a job paying $55k+ and make 2-3 times as much as a starting teacher ($35k if you're lucky and find a good school that has funding) in the same state after a year or two of experience.

</comment></comment><comment><USER37> This story strikes home with me. Like the author, I too picked up an MAT, taught for a couple years, and then left the field to pursue other opportunities. In the 3-4 years since I left, I have worked a lot less, made a lot more, and feel much more respected in what I do.

</comment><comment><USER38> "You think you know what teachers do. Right? Wrong."

So I'm wrong that I think that I know what teachers do?

Do teachers teach you how to write intelligible headlines?

</comment><comment><USER39> My wife teaches classes at a local high school as well as the university here she's successful because she works hard at it, has a natural aptitude to teach and she cares about her subjects and shows it. I think I had 3-4 outstanding teachers during my 13 years in public school and they all had these same characteristics. I had plenty of bad teaches too.

</comment><comment><USER40> My cousin is a high school teacher and posted this article on Facebook with the comment that it's like saying just because you had parents, you think you know everything there is to know about parenting.

</comment><comment><USER41> This is just a painful argument to authority.

</comment><comment><USER42> Education policy is the issue that drew me to participate on Hacker News,[1] so I'll jump in here too. I get the impression that mathattack, whose comments I enjoy reading, may have posted this article for disagreement. The Answer Sheet blog from which this guest post comes is basically a propaganda organ, and some of the guest posts from the same blog that were submitted to Hacker News in the past were exposed as hack jobs after discussion here.[2]

The obligatory disclosure here is to note that I am a classroom teacher by occupation. Over the years, I have been a teacher of Chinese to native speakers of English, a teacher of English to native speakers of Chinese (and other languages), and most recently a teacher of advanced elementary mathematics ("prealgebra" mathematics for third-, fourth-, and fifth-graders) for a nonprofit organization in my town. My HN user profile describes a bit more of my background.

Yep, classroom teaching is hard, no doubt about it. It has emotional rewards that some people value highly enough that it is a sought-after occupation, not a labor-shortage occupation, and that has the most to do with teacher compensation. Classroom teaching by teachers in private practice (like me) can also be poorly compensated (relative to the difficulty of doing the job well) because most clients have already paid for "free" lessons at the local public schools through their taxes, and will only pay out of pocket for a private lesson if it is truly superior in some way. "In modern times [as contrasted with ancient times] the diligence of public teachers is more or less corrupted by the circumstances which render them more or less independent of their success and reputation in their particular professions. Their salaries, too, put the private teacher, who would pretend to come into competition with them, in the same state with a merchant who attempts to trade without a bounty in competition with those who trade with a considerable one. . . . The privileges of graduation, besides, are in many countries . . . obtained only by attending the lectures of the public teachers. . . . The endowment of schools and colleges have, in this manner, not only corrupted the diligence of public teachers, but have rendered it almost impossible to have any good private ones." \-- Adam Smith, The Wealth of Nations, Book V, Part 3, Article II (1776)

A couple of the comments posted here before I arrived in the thread mention the particular skills that a teacher needs to have to teach a class effectively. There is much interesting research on this coming from the charter school movement, with some of the best how-to research coming from the Teach Like a Champion[3] project. I love learning about new ways to be a more effective teacher. Besides actual teacher skills, another grave problem in United States school is extremely poor teaching materials[4] and I devote hundreds of hours to curriculum planning and seeking out the best available textbooks[5] for the subjects I teach.

A good teacher is worth a lot.[6] We would not go far wrong by saying that a good teacher is literally worth his or her weight in gold. But the tricky issue in school administration is distinguishing effective from ineffective teachers. To ensure that school leaders have incentives to find and reward the best teachers, we need to make sure that learners (or the adult guardians of minor learners) have the power to shop, the power to refuse the services of an ineffective teacher and to seek out the services of an effective teacher. Teachers will gain both more pay and more respect if learners gain power to shop.

[1] [http://news.ycombinator.com/item?id=4728123](http://news.ycombinator.com/item?id=4728123)

[2] [https://news.ycombinator.com/item?id=3327847](https://news.ycombinator.com/item?id=3327847)

[3] [http://teachlikeachampion.com/](http://teachlikeachampion.com/)

[4] [http://open.salon.com/blog/annie_keeghan/2012/02/17/afraid_o...](http://open.salon.com/blog/annie_keeghan/2012/02/17/afraid_of_your_childs_math_textbook_you_should_be)

[5] [http://www.artofproblemsolving.com/Store/viewitem.php?item=p...](http://www.artofproblemsolving.com/Store/viewitem.php?item=prealgebra)

[6] [http://hanushek.stanford.edu/publications/valuing- teachers-h...](http://hanushek.stanford.edu/publications/valuing-teachers-how- much-good-teacher-worth)</comment>


Squeak: A Language for Communicating with Mice (1985) [pdf] - <AUTHOR> http://ordiecole.com/squeak/cardelli_squeak1985.pdf <comment><USER2> [Computer] Mice

<comment><USER3> [Not Smalltalk] Squeak.

<comment><USER4> Not Squeak[JS]

<comment><USER5> Let's be honest with ourselves, we knew that from the date.

As the days roll on today, we're rapidly approaching a time when every word in the dictionary has an associated package on NPM. There's an epoch I look forward to that I call "peak js" when we have to start fracking for package names. NPM will change their community guidelines so people can reserve things like "HolocaustJS" (a templating engine for dockerizing existential dread about lives wasted naming things on npm, Fork me on github!) -- because everything less offensive will be taken.

Money will be spent reviving dead languages by sampling the acoustics encoded in the drying bricks of their temples so that we'll have new words to apply npm packages to. That's the kind of hellscape we're headed for, unless we act now to reduce, reuse and recycle.

<comment><USER6> You're right there will be a change, but I don't think it'll be, as you suggest, towards fascism.

The notion of a centralized namespace is obselete. We will just have thousands of packages called "Squeak" and we will socially key packages by universe/name instead of name. In the default case the universe will be implied so it won't even look that different from today.

But there will be infinite universes. We will spread out. Just like what's happening in culture now. (The recent Twitter/Facebook/YouTube bannings being a perfect example of namespace fracturing)</comment></comment></comment></comment></comment>


Sleepless in Silicon Valley - <AUTHOR> https://www.economist.com/business/2019/05/18/sleepless-in-silicon-valley <comment><USER2> Another view on the Oura thing: [https://www.medpagetoday.com/practicemanagement/informationt...](https://www.medpagetoday.com/practicemanagement/informationtechnology/78317)

It's rather skeptical. Choice quote:

[...] The SRI researchers studied 41 healthy adolescents and young adults (average age 17). Sleep data were recorded using the Oura ring and standard PSG on a single laboratory overnight. Metrics were compared using Bland-Altman plots and epoch-by-epoch analysis.

The ring accurately detected "light" and "deep" sleep in 65% and 51% of the sleep epochs, respectively. It also accurately detected 61% of REM sleep epochs, with an overall overestimation of PSG REM sleep (by about 17 min). When the ring misclassified PSG REM sleep, the algorithm usually classified the epoch as "light sleep" (76%).

These data suggest that the Oura Ring is virtually useless in telling you if you are in REM sleep versus deep or light sleep. [...]

<comment><USER3> It doesn't matter so much how accurate it is, as long as it's consistently inaccurate.

I don't care if my scale at home is perfectly accurate. I care about knowing that my weight is going up/down.

<comment><USER4> I care if my scale at home is accurate. I don't want to know if my weight is going up or down, I want to know what I currently weigh so I can decide what I need to do about it.

<comment><USER5> Your example seems to disagree with your premise. If someone tells me I weigh "9239" this means nothing to me, unless in context of whether it's going up or down, and how it is related to others of my height (and age and gender, perhaps).

I don't care that I weigh some multiple of an SI unit, or some fraction of a car. I care about my weight relative to others and my history.

<comment><USER6> If you care about your weight relative to others, then it has to be accurate, no? Because how would you compare your weight unless you had a bunch of people using your scale.

<comment><USER5> True, but given that it's more difficult to change your weight than it is to find someone of a different weight, I'd rather live my whole life with a scale that might be reading (say) 5lbs high or low, rather than a scale that _fluctuates_ between 5lbs high or low from measurement to measurement.

</comment></comment></comment></comment></comment></comment><comment><USER7> Tbh the oura ring has been a game changer for a data nerd like me. I can easily see how some exercise in the day actually impacts my HRV[1] and then the quality of my sleep. Had a heavy night of drinking? Watch what the oura ring reports not just on the same night but even the next night :) Basically if you're thinking of starting your own "protocol" for sleep and would like to A/B test what works and what seems like superfluous ceremony, the oura ring is a cost-effective way to measure the effectiveness of said protocol.

I think the protocol described in the article isn't anything terribly new. Most folks on HN know that blue light actually messes with sleep so if you're planning on using a screen until right before you goto bed it's a great idea to use the blue-light canceling computer glasses. Mindfulness meditation is generally a great practice to calm oneself and be reflective. I don't personally sleep at 8:45pm (rather, 11:45pm) but I do have my meal a few hours before I goto bed. I also don't drink much water closer to bedtime so I'm not rudely awakened in the middle of the night to urinate. I live in a place where the black-out blinds aren't a necessity. I've never messed with deep sound waves.

Of course, some folks will exclaim "Well I don't need a device to give me a report card on how well it thinks I slept!" ¯\\_(ツ)_/¯

[1] [https://ouraring.com/heart-rate-variability- basics/](https://ouraring.com/heart-rate-variability-basics/)

<comment><USER8> Why use this over an apple watch or fitbit?

<comment><USER9> Does the Apple Watch do sleep tracking out of the box now? I was one of the 5 people who bought a Microsoft Band, and I really enjoyed the sleep tracking features. I still haven't pulled the trigger on an Apple Watch since switching to and iPhone because it (used to?) lack sleep tracking as a feature.

<comment><USER10> No. It still is intended to charge overnight. Apple store sells other sleep tracking products at this time.

<comment><USER11> It charges fast enough that you can wear it almost 24/7 if you plan ahead and charge for a bit in the morning and at night

[https://david-smith.org/blog/2015/09/21/how-to-wear-your- app...](https://david-smith.org/blog/2015/09/21/how-to-wear-your-apple- watch-24-slash-7/)

</comment></comment></comment></comment></comment><comment><USER12> My sleep tracking now consists of putting my APAP on to counteract my sleep apnea, falling asleep within seconds because I'm like Pavlov's sleeping baby dog because of the machine, and then waking up and seeing what the machine says re: how long it has been pushing air in my nose.

It works surprisingly well, actually. If I only got 6.5 hours of APAP last night, then I will pretty reliably go to bed a little earlier tonight.

My takeaway from this is that someone should make a fake CPAP face mask for people who don't need a CPAP that tells you how long you've been wearing it. I'm 100% convinced that the mask itself is what makes me fall asleep so fast. Once the mask is on, my brain knows it's time for sleep and complies. I guess I don't know if that's the same for all APAP/CPAP/Bi-PAP users though.

<comment><USER13> I'm curious - How do stomach sleepers adjust to these masks? Or does sleep apnea only affect back sleepers? It would be impossible for me to sleep wearing a mask.

<comment><USER14> There are masks and pillows specifically designed for stomach sleepers. But stomach sleeping is somewhat uncommon, and plenty of people who sleep in more conventional positions can't adapt to sleeping with a CPAP, so you probably just have to find out yourself.

FWIW, I have sleep apnea and I'm a strict side sleeper. I also had a real tough time getting used to sleeping with something attached to my face. Sometimes I still take it off if I'm awake too long during the 2-4am time period, but most nights I sleep through without even noticing. I use a nasal mask, though, I absolutely have not ever been able to tolerate a full face mask.

</comment></comment></comment><comment><USER15> "Why We Sleep" by Matthew Walker is an excellent book for those interested in what science has to say about sleep (disclaimer: it's excessively good for you)

<comment><USER14> Sometimes I wonder if Mr. Walker is paying people at HN to talk about his book :). Comes up more often than I'd expect.

<comment><USER16> He should write me a check, I've recommended that book on HN and offline to at least 5 new readers.

</comment></comment></comment><comment><USER17> My hack is just fall asleep when putting the kids to sleep and wake up whenever I feel like. If I've been pushing hard, sometimes I'll take all 10 hours, other nights I'm up at 4am ready to work.

<comment><USER18> I wish my two year old would sleep 10 hours a night.

</comment></comment><comment><USER19> [https://outline.com/E7sbMG](https://outline.com/E7sbMG)

</comment><comment><USER20> Hmm another sleep article.

I'll share what I do. After being in the Army for a while, and waking up at 430 and going to bed at close to midnight for a long time during the week (there's no real "sleep schedule" overseas though) I've been working on tuning my sleep cycle for the seasons to great success. Over the last year I've been slightly altering my alarm each night based on when sunrise is (plus going to bed earlier/later as the days lengthen/shorten), and it's significantly improved how quickly I fall asleep, how easily I get out of bed in the morning, and how rested I feel. I'm not a huge "fitness tracker" guy (still analog in that regard, with a notebook for workouts instead of some app or a spreadsheet). No idea if there's any science behind any of what I'm doing and frankly I don't care. It works great for me.

<comment><USER21> Can you add more details on how you handle seasons? This is something I've been wondering about. Do you shorten/lengthen your sleep? Or just shift it to always wake up at sunrise? I think shifting seasons might be one "natural" thing which our biology is not "naturally" attuned to, and a fixed-length day would probably be better (maybe we'll have it in the future on a space colony, by I digress).

<comment><USER20> I think it's as simple as I sleep more in the winter and less in the summer and about the same between spring and fall. Not anything crazy. It's probably an average of ~7 hours in the summers and 8+ in the winter. I live in a high latitude city and last year I figured I'd just try it, given how much more light we get in the summer. Work is a little hard to accommodate in the winter sometimes, but otherwise I think I'll probably do this for the rest of my life.

</comment></comment></comment><comment><USER22> I use a Samsung smartwatch that came with my Samsung S9 as a package deal.

The sleep tracker has been useful to me in tracking my quantity/quality and average sleep.

I still get to spend a few weeks a year a few times a year assessing human performance.

Sleep is absolutely critical to human physical, mental, emotional, and social performance.

And as the parent of adolescent children who are technology driven, monitoring their "digital nutrition", mixing in other activities, ensuring they are well fed/hydrated, and compelling good sleep hygiene is absolutely essential to their development as adolescents towards adulthood.

It's quite shocking to observe how common it is for both adults and children to be seen suffering from poor sleep hygiene.

</comment><comment><USER23> sleep, healthy eating, and exercise are fundamental to living a long and fulfilling life. I think it's great that people are trying to determine in a quantitative way when we've "slept good." I sure as hell can use a device that can tell me if I've slept well, so i can try to establish a pattern between how i feel the next day and what these devices tell me as to how i slept.

<comment><USER2> What would you do with that data, that you cannot do with a simple journal you'd fill out each morning?

</comment></comment><comment><USER24> Re/ oura rings... anyone else paranoid of a private company having access to intensely personal data?

If I were an insurance company I'd be lobbying the shit out of these guys to see how much they'd charge me to get my hands on it.

(and yeah, I read Oura's privacy agreement already... was less than impressed)

<comment><USER25> Of course, but this is just another in a long train of abuse-potential. The technology isn't the choke point for protecting our rights, and individual consumer choices will never be revolutionary enough to alter the terms of consumption.

</comment></comment><comment><USER26> Polysomnography seems like an area in desperate need of innovation to improve efficiency and lower cost. It is far too expensive for the entire undiagnosed sleep-deprived population to have a single sleep study let alone for those already diagnosed to have more frequent observation.

</comment><comment><USER27> I recently went through a sleep study, and the doctor was openly aggravated by how current trends and devices focus on "deep sleep", when it's actually "light sleep" that we need to regain our mental focus.

<comment><USER28> Really? Care to elaborate?

<comment> xkcd-sucks REM is "light sleep", one 3 hour-ish sleep cycle is "NREM stage I -> NREM stage II -> NREM stage III -> REM" where REM is considered "pretty close to awake" and NREM stage numbers are "progressively deeper". Deeper basically means lower body temperature, less movement, and slower breathing.

This is on the basis of clustering/pattern matching body movement, body temperature, and some brain wave/MRI crap.

VERY broadly speaking, "deep" NREM stages are important for "body health" while REM is important for maintenence of memories and "mental health".

As with anything in neurobiology, it's "emerging evidence suggests that..." and nobody _really_ knows what's going on. Except all evidence suggests sleeping less is bad for pretty much everything.

The dynamics of sleep state transitions are also pretty meaningful, e.g. time it takes to move from one stage to the next, whether there's "backwards" transitions, etc. For example, sleep deprivation lengthens deep NREM time, lowers latency from wake -> NREM I, and shortens the entire sleep cycle.

<comment><USER28> huh, that is fascinating to hear. Will definitely be keeping an eye on this space, thanks for the info.

</comment></comment></comment></comment><comment><USER29> I've found the app recommended by wirecutter

[https://thewirecutter.com/reviews/best-sleep-tracking- app/](https://thewirecutter.com/reviews/best-sleep-tracking-app/)

Quite accurate, at least for time to sleep, and time asleep. I think the REM, NREM etc is mostly noise, if you are getting 8+ hours a night every night (super hard to do!) the quality of sleep should be fine.

The best thing is to set a "go to bed" alarm, for night owls like me its so easy to say you go to bed "around 10" when in fact it can be much later.

</comment><comment><USER30> This is a great example of how quantitative facts decide over the qualitative evaluation of all things in Silicon Valley - including deeply personal matters like sleep and even relationships. I've been living in Silicon Valley for a while now and I can't believe my eyes and ears sometimes!

</comment><comment><USER31> > Techies obsess about OKRs (objectives and key results), KPIs (key > performance indicators).

What an over-generalization.

<comment><USER32> This article is published by an entity/author obsessing over SEO, CTR, CPM, CPI (basically ad $$$)

</comment></comment><comment><USER33> So why aren't we just using Sleep As Android like normal people, and not using some weird devices to track it? Absolutely don't understand the fetish of expensive devices just to track sleep, and I'm the one here with the non-24hr circadian rhythm.

<comment><USER34> Not everyone has an Android phone and some people don't like keeping their phones right next to their bed.

I have a fitbit charge 2 and that thing does more than just track sleep - heart rate, VO2 max, steps, connected GPS for running. So the expensive device is not a bad investment IMO.

</comment></comment><comment><USER35> In New Zealand, electric blankets are very common because (for the most part) we're too poor to live in insulated houses. It's hilarious that they've been re-discovered as a sleep hack for hyper-wealthy californians.

<comment><USER36> Yours are probably just heating. Theirs are cooling

</comment></comment><comment><USER37> though this article is basically an ad for the oura ring, i do think sleep hygiene is an interesting topic and worthy of conversation. Would love to hear what the HN crowd thinks.

</comment><comment><USER38> Apart from being a snarky article, the author does not propose any actual solutions. So what if a few folks try to hack sleep? Whatever floats their respective boats....

<comment><USER39> > It is hardly surprising that techies are not getting enough sleep, given the > industry's culture of long hours, and the widespread notion that for a true > entrepreneur, everything else in life is secondary to succeeding at work.

This article was very snarky, even for the economist. It seems distinctly below their usual standard of quality with broad generalisations such as the above, seemingly contradicted by an anecdote about Bryan Johnson and others' bizarre sleep practices.

For me this article would have been a lot better if it focused on the sleep tech industry, and applied a more measured and evidence-based approach to its silicon valley criticisms, some of which certainly are relevant and worthy of discussion.

</comment></comment><comment><USER40> I have a question for those far more into sleep hygiene than I am: is it possible to get blue light-blocking prescription lenses for normal glasses?

<comment><USER41> Yes. Every lenses has this option by now.

</comment></comment><comment><USER42> > radiation-blocking Faraday tents

Is there any research that indicates this would be beneficial in any way?

</comment><comment><USER43> Paywalled, but based on the free paragraphs, I was kinda surprised that it didn't talk about the other factors that may affect sleep.

Currently reading 'Why we sleep' which is a fascinating book about the importance/history/evolution of sleep across species and time. (Highly recommend it -- definitely regretting all the sleepless/low sleep nights)

At a high level, my understanding is that the duration/quality of sleep depends on physiological, mental and environmental conditions.

It sounds like the focus of the article was on environmental (I would definitely love to sleep with zero light/sound).

Similarly, the 5-10 mins meditation may help, but if you're stressed out or have something on your mind, that can still keep you awake or wake you up.

You can make sure not to eat/drink anything by that time (6pm) but effects of caffeine/other foods you might have eaten earlier can impact your sleep quality.

Finally, the right physiological/chemical changes need to occur (melatonin/REM cycles/tired from physically exhausting activities) for you to actually be sleepy. Most people can't just sleep on command, although, you might be able to build/force the habit.

<comment><USER2> >(I would definitely love to sleep with zero light/sound).

You might not actually like it. Try a sensory deprivation tank and see how that works for you.

To reduce the noise you can always reach for quality earplugs, a sleeping mask, and blackout curtains.

</comment></comment><comment><USER44> Now I want to get an Oura! Are ads getting smarter?

</comment><comment><USER45> The accuracy of estimating sleep stages using heart rate and movement metrics is an interesting, and tenuous, subject. WRT to Fitbit and Oura the TLDR is that Fitbit and Oura aren't accurate for slow wave (Deep Sleep) or REM. However, Fitbit is better at REM detection [1][2] than Oura.

While sleep staging can be useful for identifying case sleep disorders, we know that the brain self-optimizes the stages of sleep you go through.

So, what's far more important than worrying about your rem or deep is optimizing getting time in any stage of sleep. Each stage is critical in a different way.

If you care about improving your performance the measures you should care about—backed by strong scientific consensus and a plurality of randomized evidence—are sleep debt and where you are in your circadian rhythm. Sleep scientists call this the two factor model

This reality drove us to create a sleep improvement app, called Rise ([[https://www.risescience.com](https://www.risescience.com/)](https://www.risescience.com\]\(https://www.risescience.com/\))). We started both our research and company initially for elite athletes. We tell them what to do to improve their sleep tonight based on science. It's currently being used by both professional and collegiate teams across the NFL, MLB, NBA, MLS, and NCAAF.

We've been taking what we've learned from athletes and adapting for us regular folk.

If you're interested in joining our beta, sign up here: [[http://bit.ly/hacker-friends](http://bit.ly/hacker- friends)](http://bit.ly/hacker-friends\]\(http://bit.ly/hacker-friends\))

[1] [[https://www.ncbi.nlm.nih.gov/pubmed/28323455](https://www.nc...](https://www.ncbi.nlm.nih.gov/pubmed/28323455\]\(https://www.ncbi.nlm.nih.gov/pubmed/28323455\))

[2] [[https://www.ncbi.nlm.nih.gov/pubmed/29235907](https://www.nc...](https://www.ncbi.nlm.nih.gov/pubmed/29235907\]\(https://www.ncbi.nlm.nih.gov/pubmed/29235907\))

</comment><comment><USER46> Bet they'll have us walking on our hands before the century is over.</comment>


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<comment><USER2> It looks nice, i use <http://crossbrowsertesting.com/> which is similar.

</comment><comment><AUTHOR> We launched this today, I'd be interested in what you think about it!

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<comment><AUTHOR> Thanks. We launched the website (automated testing) in January 2012.</comment></comment></comment>