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Letters between Backus and Dijkstra (1979)

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Re: Letters between Backus and Dijkstra (1979)

#101

Post by mcguire »

justin66 wrote: post #13
vanderZwan wrote: post #11

Earlier quoted context omitted.

Funny thing is that Alan Kay himself often comes across just as arrogant these days. "Comes across", because more often than not I think it's more likely that people who are too pleased with themselves don't like to be told that, really, what they've achieved isn't good enough, or even misguided. Even if, or perhaps especially if, the person who tells them that (Dijkstra when it comes to programming, Kay when it come…

What recent talks has Kay given? To be honest, my only criticism of him based on what I've seen the last decade is that he's reusing too much of the same material, even though he certainly has a lot more to say.

You guys realize he's right over there https://news.ycombinator.com/item?id=11799963, right?

:-)

Re: Letters between Backus and Dijkstra (1979)

#102

Post by vanderZwan »

mcguire wrote: post #101
justin66 wrote: post #13

Earlier quoted context omitted.

What recent talks has Kay given? To be honest, my only criticism of him based on what I've seen the last decade is that he's reusing too much of the same material, even though he certainly has a lot more to say.

You guys realize he's right over there https://news.ycombinator.com/item?id=11799963 , right? :-)

Did not expect that! I hope he read my comments about him as the implied compliments I intended them to be; being an interaction designer he's one of my biggest heroes! :)

Re: Letters between Backus and Dijkstra (1979)

#103

Post by alankay1 »

acidflask wrote: post #70
dang wrote: post #35

Earlier quoted context omitted.

Thank you for going to the trouble of sharing this amazing material! I'd also like to hear about the historical paper you're working on. We've taken the "arrogance" quote out of the HN title and replaced it with a neutral description of the letters—perhaps a bit too neutral, given how fabulous the post is. But HN readers can figure that out for themselves, especially once a post gets so high on the front page.

The paper is about, among other things, the history of the array data structure. It's far too early to advertise, but you can see a very early version on my GitHub account. :) I was surprised to discover recently that the word 'array' prior to 1950 was used exclusively to describe two dimensional tables of numbers that one might find in a matrix or determinant. But by the advent of FORTRAN I in 1957 and ALGOL 58, 'ar…

Priority is tricky to nail down e.g. the EDSAC was operational a year before the Mark 1 (which actually was not operational until 1949). Because of the "B" Williams Tube which held the two index registers of the Mark 1, many other manufacturers -- e.g. Burroughs -- later called their index registers "B registers". (Also, I think the Univac I and II were successful commercially, and earlier than the 704.)

I started programming in earnest and for money in 1961 mostly in machine code on a variety of machines, and I'm pretty sure that the notions of single dimensional sequential locations of memory as structures (most often called arrays, but sometimes called lists), predated the idea of index registers. This is because I distinctly remember being first taught how to move through arrays sequentially just by direct address modification -- this was called indexing in the Air Force -- and later being introduced to the index register or registers -- depending on the machine.

My strong guess (from above) is that the array as sequential memory accessed by address modification of some kind was a primary idea in the very first useful computers in the late 40s, and that this idea pre-dated index registers.

It would be well worth your time to look at the instruction set of EDSAC, and try writing some programs.

Re: Letters between Backus and Dijkstra (1979)

#104

Post by alankay »

acidflask wrote: post #91
alankay wrote: post #83

Earlier quoted context omitted.

This quote keeps on showing up out of context. Edsger and I got along quite well. He loved to be the way he was and pushed it. His friend Bob Barton (the great genius of the B5000 design) was very similar in loving to push buttons and being very critical of the not-quite-a-field that we have. When the U of Utah faculty complained to Dave Evans about Barton, Evans said "We don't care if they're prima donnas as long as…

Would you happen to have any insight into the question that brought me to go dig through old letters in a library in the first place? https://news.ycombinator.com/item?id=11799143

Priority is tricky to nail down e.g. the EDSAC was operational a year before the Mark 1 (which actually was not operational until 1949). Because of the "B" Williams Tube which held the two index registers of the Mark 1, many other manufacturers -- e.g. Burroughs -- later called their index registers "B registers". (Also, I think the Univac I and II were successful commercially, and earlier than the 704.)

I started programming in earnest and for money in 1961 mostly in machine code on a variety of machines, and I'm pretty sure that the notions of single dimensional sequential locations of memory as structures (most often called arrays, but sometimes called lists), predated the idea of index registers. This is because I distinctly remember being first taught how to move through arrays sequentially just by direct address modification -- this was called indexing in the Air Force -- and later being introduced to the index register or registers -- depending on the machine.

My strong guess (from above) is that the array as sequential memory accessed by address modification of some kind was a primary idea in the very first useful computers in the late 40s, and that this idea pre-dated index registers.

It would be well worth your time to look at the instruction set of EDSAC, and try writing some programs.

Re: Letters between Backus and Dijkstra (1979)

#105

Post by ScottBurson »

eruditely wrote: post #78
ScottBurson wrote: post #59

Earlier quoted context omitted.

There's an interesting summary of the debate about this study on Medscape [0]. Failing to tell a patient that strenuous exercise might be fatal sounds like an error to me! As it happens, my maternal grandmother was killed by a medical error (before I was born). She went in for some kind of routine surgery and didn't make it. Decades later, when the doctor involved died, among his effects were found a letter he had wr…

tell us more about your grandmother's story.

I don't know anything else about it, except I can add that it would have been about 1952, in Alabama.

Re: Letters between Backus and Dijkstra (1979)

#106

Post by kazinator »

frank_jaeger wrote: post #76
sukilot wrote: post #41

Earlier quoted context omitted.

I don't know what your friend said, but the "errors are #3 killer" is a twisted fact. It comes from assigning "error" at the cause of death of every injury or illness that might have been non-fatal if every perfect test, advance in practice, technology, and mode of care were applied. It isn't a measure of how many otherwise healthy people were killed by errors that introduced new complications. One of highlighted exa…

A doctor failed to tell a CHILD about an appropriate level of activity for his condition, and you honestly have the gall to put quotes around that error?

That child could have easily died running involuntarily from bullies or dogs. Or from having his heart race due to anything else: being startled, nervous, or excited on a first date or whatever.

He didn't die while undergoing a medical procedure; he died of a bad ticker.

The medical establishment didn't cause his heart ailment, it just neglected to inform him. That is unfortunate, but it is somehow not the in the same category as, say, being treated for a broken leg, and given a fatal overdose of some painkiller.

Honest accounting for deaths due to medical error must only count situations when someone dies of something irrelevant, not directly connected to the condition for which they are treated. (Certainly not of the condition for which they are treated, especially if that kind of condition itself carries a reasonable probability of causing death!) That cause of death which occurs must not be a recognized risk factor in that kind of treatment (when that treatment is correct).

The key reasoning is that without any medical intervention at all, the child would also have likely died, and of the same thing.

If we count as a "death due to medical error" a situation in which medicine merely failed to prevent a death, that has to be very well justified. This means that it was very probable that if the mistake had not been made, the patient would have made a full recovery: their condition would have cleared away to the point of that condition no longer being a death risk, and that this positive outcome is virtually guaranteed in such cases when the correct treatment is applied.

The advice not to ever strain yourself physically for the rest of your life or get excited is not a treatment which results in the condition being cured. The condition remains in place, along with the risk of dying.

Re: Letters between Backus and Dijkstra (1979)

#107

Post by vanderZwan »

alankay wrote: post #83
justin66 wrote: post #9

"I don't know how many of you have ever met Dijkstra, but you probably know that arrogance in computer science is measured in nano-Dijkstras." - Alan Kay

This quote keeps on showing up out of context. Edsger and I got along quite well. He loved to be the way he was and pushed it. His friend Bob Barton (the great genius of the B5000 design) was very similar in loving to push buttons and being very critical of the not-quite-a-field that we have. When the U of Utah faculty complained to Dave Evans about Barton, Evans said "We don't care if they're prima donnas as long as…

> He loved to be the way he was and pushed it.

So are you saying that you said this as a friendly jab, knowing he would probably love it himself?

> His comment about OOP (a rather different kind of thing at Xerox PARC than what the term means today) did not bother any of us at all

So he did actually say that quote about OOP? Do you happen to know the source?

Re: Letters between Backus and Dijkstra (1979)

#108

Post by shiggerino »

jamesblonde wrote: post #28
vanderZwan wrote: post #15

You know, I'm wondering: could part of Dijkstra's reputed arrogance be due to a cultural difference? I'm Dutch, and bluntly calling out flaws in each other's work is not considered all that rude over here; it's almost the opposite: not calling someone out on their flaws implies we either consider them a lost cause or not worth the hassle of educating. I almost got fired from a teaching position in Sweden because I to…

I'm a lecturer in Sweden, and i know how you feel :) To quote some students on a list "What's this nonsense with independent thinking? Nobody ever told us we had to do that."

I can concur. The Swedes have turned into an absolute disgrace. Constant late-coming, talking and other distracting behaviour. They have become a nation of low moral fibre, pure and simple. I say become, because I refuse to believe this was the modus operandi of the likes of Linnaeus, Arrhenius, Berzelius, Celsius, etc.

I'm going through the motions myself, at an institution that shall remain nameless, knowing how kindly they take to criticism here.

Re: Letters between Backus and Dijkstra (1979)

#109

Post by internaut »

eruditely wrote: post #78
ScottBurson wrote: post #59

Earlier quoted context omitted.

There's an interesting summary of the debate about this study on Medscape [0]. Failing to tell a patient that strenuous exercise might be fatal sounds like an error to me! As it happens, my maternal grandmother was killed by a medical error (before I was born). She went in for some kind of routine surgery and didn't make it. Decades later, when the doctor involved died, among his effects were found a letter he had wr…

tell us more about your grandmother's story.

Ack, I thought you were talking to me. Sorry!

Re: Letters between Backus and Dijkstra (1979)

#110

Post by Pica_soO »

Jtsummers wrote: post #64
Retra wrote: post #56

Earlier quoted context omitted.

While I would agree with that in principle, I think the word "violence" is being stretched a bit. Being unforgiving, stubborn, demanding, hard-hearted, or anything adherence to logic might be claimed to imbue are not acts of violence, even if they are emotionally hurtful to others.

Emotional harm is still violence. it is not a strictly physical phenomenon.

I was molested by the universe, ever since i was evicted from the save space of the womb. ;)

I would feel so ashamed, for soiling myself with self-pity in public and to perceive the distance others take from me as a success of my output.

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