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The seven specification ur-languages

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Re: The seven specification ur-languages

#41

Post by culi »

simiansays wrote: post #39
culi wrote: post #31

Earlier quoted context omitted.

> If so, wouldn't it be incompatible with the theory of evolution? It's very much not. The thing is that every model is a lie, but they can often be very useful lies. The reason we use taxonomic trees is because they're "good enough" but there are tons of places where this really breaks down. For example, horizontal gene transfer is a huge problem in microorganisms. If you take a soil fungi from one environment and p…

I get convergent evolution, but among large (let's say 10g+) organisms, I'm not aware of convergent evolution resulting in compatible species (with fertile offsping) that would not otherwise have been compatible? I'm super rusty on this topic, but if there is theory that large organism actual DNA-level speciation (resulting in individuals who cannot reproduce together) has eventuated to convergence back to a new spec…

I never once mentioned convergent evolution. Convergent evolution is irrelevant in modern phylogeny-based taxonomy. I'm talking about the actual genes themselves

Re: The seven specification ur-languages

#42

Post by jacobr1 »

simiansays wrote: post #28
jmillikin wrote: post #14

Earlier quoted context omitted.

The thing with taxonomies is that trying to make a category more precise tends to exclude things you want to include in it, and vice-versa. It is especially easy to find examples of this in nature, because nature has existed since long before humans had opinions about how things should be organized. What is a cat? It's a small furry quadruped in family Felidae. - Exception: cats may be quite large (lions, tigers). -…

I definitely understand that the majority of taxonomies are problematic for the reasons you cited. When OP said "no such thing as a tree", I thought OP meant a taxonomic tree, not a literal plant tree, hence my example of binary numbers! Thanks for clarifying. That said, taxonomic groupings can have both wide consensus and be useful, can't they? (Hand on chin... monotremes? hominids??)

The CS specific analogy might be, "Abstractions are leaky," or more broadly the, "map is not the territory."

Any complex-phenomena that is modeled with with a simplification will have places where that simplification fails. But models can still be highly useful, you just need to choose an appropriate level of abstraction, accept and manage any tradeoffs with exceptions, and move to better paradigm if one emerges.

Re: The seven specification ur-languages

#43

Post by btilly »

simiansays wrote: post #2

> All taxonomies are broken, full stop. Your categories are gonna be completely wrong and everybody’s going to argue over every single thing. There is no such thing as a tree. Is this a serious statement? If so, wouldn't it be incompatible with the theory of evolution? Would an alien taxonomy of human binary numbers not be a legitimate tree?

Where in a taxonomy of humans would you put the estimated 8% of our genome that is from viruses trapped in our DNA?

https://www.science.org/content/article/ancient-virus-may-be... https://www.discovermagazine.com/planet-earth/mammals-made-b...

Re: The seven specification ur-languages

#44

Post by darksaints »

rodelrod wrote: post #35
darksaints wrote: post #21

Earlier quoted context omitted.

I get that the prefix entered our lexicon from german, but frankly you don't have enough information to say that there is no relation. The city of Ur is 4000 years older than Old High German, and Ur has been used as a metaphor for the origin of things for thousands of years, even ancient Greece. You can't definitively say that the idea of Ur as an origin of civilization had no influence on german.

> frankly you don't have enough information to say that there is no relation I'm not a scholar of this subject. If there is good scholarship out there presenting good arguments in your direction I'll take it. I was just helping out a fellow that has a doubt with my best knowledge of the subject, which is not just a guess. > has been used as a metaphor for the origin of things for thousands of years, even ancient Gree…

Yeah, on second glance I might be confusing some of my sources here. I can’t seem to find what I thought I was remembering.

Regardless, there seems to be a significant distinction between words using a concatenated ur prefix and those using a hyphenated ur-(noun) prefix. In this case, the usage does seem to imply an original language from which all others are derived, and the metaphor seems apt even if it is not historically accurate to say that’s where it came from.

Re: The seven specification ur-languages

#45

Post by xavxav »

xavxav wrote: post #40
xavxav wrote: post #27

This is a good list but is almost more accurately called a list of modeling languages. At the very least it’s a very particular interpretation of specification, which makes sense from a TLA+ expert but is incomplete. In particular I think there are a few candidate ur-specification languages that could be included: * first-order logic, this captures what almost every deductive verifier uses, and has a surprisingly ric…

Based on the state of academic conferences in formal methods, I would have 4 languages: temporal logic, first order logic, concurrent separation logic and dependent type theory. This categorization provides generalizing powers because tools, techniques and limitations mostly map onto it. * temporal logic: almost exclusively used by model checkers. Usually propositional, has limited/no support for quantifiers. Also us…

On second thought, these are mostly too closely related, I think that if you want to truly find the ur-specification languages this is closely related to Girard's research program. Specification languages are intrinsically tied to a notion of truth and also of proof (method of establishing / showing truth), these are central questions in Girard's work.

I think a revised list should also include proof-nets, and other weirder specification languages like the [flower calculus](http://www.lix.polytechnique.fr/Labo/Pablo.DONATO/drafts/FJ....) or stellar resolution. These also stretch the usual interpretation of language as a syntax tree.

Re: The seven specification ur-languages

#47

Post by nerpderp82 »

leetrout wrote: post #6

I am confused - what does "ur-" prefix mean?

I too am confused about what both authors think the definition of "ur-" is in both of their contexts. https://news.ycombinator.com/item?id=35818607

Nor do I understand why for TLA+, the second author needs to demarcate a dichotomy between language/programming language and specification language. And then the next thing they do is Tear Down the Taxonomy! Tear it down from the beginning.

Re: The seven specification ur-languages

#48

Post by jerf »

hwayne wrote: post #32
throw10920 wrote: post #22

Earlier quoted context omitted.

I'm 95% sure that the author (who is on HN[1]) is at least referring to the article "There's No Such Thing As A Tree" in his line "There is no such thing as a tree." - regardless of the fact that the article as a whole isn't about trees made of wood. It's possible that he's additionally making a double entendre about abstract tree structures. [1] https://news.ycombinator.com/user?id=hwayne

Yeah, I was thinking about biological trees. In retrospect, I should've gone with "there's no such thing as a fish."

My favorite example is "berry". Everything that you think is a berry isn't botanically a berry... but tomatos and bananas are.

OK... technically it's almost everything you think is a berry isn't. But it sure feels like it's everything.

Re: The seven specification ur-languages

#49

Post by Jtsummers »

nerpderp82 wrote: post #47
leetrout wrote: post #6

I am confused - what does "ur-" prefix mean?

I too am confused about what both authors think the definition of "ur-" is in both of their contexts. https://news.ycombinator.com/item?id=35818607 Nor do I understand why for TLA+, the second author needs to demarcate a dichotomy between language/programming language and specification language. And then the next thing they do is Tear Down the Taxonomy! Tear it down from the beginning.

> I too am confused about what both authors think the definition of "ur-" is in both of their contexts.

I'm confused why you're confused. The original author (of "The seven programming ur-languages") stated what they meant by an ur-language:

> I am aware of seven ur-languages in software today. I’ll name them for a type specimen, the way a species in paleontology is named for a particular fossil that defines it and then other fossils are compared to the type specimen to determine their identity. [emphasis in original]

They didn't hide their meaning, they laid it out right before listing the languages and then explaining why they selected them.

Re: The seven specification ur-languages

#50

Post by jhbadger »

simiansays wrote: post #28
jmillikin wrote: post #14

Earlier quoted context omitted.

The thing with taxonomies is that trying to make a category more precise tends to exclude things you want to include in it, and vice-versa. It is especially easy to find examples of this in nature, because nature has existed since long before humans had opinions about how things should be organized. What is a cat? It's a small furry quadruped in family Felidae. - Exception: cats may be quite large (lions, tigers). -…

I definitely understand that the majority of taxonomies are problematic for the reasons you cited. When OP said "no such thing as a tree", I thought OP meant a taxonomic tree, not a literal plant tree, hence my example of binary numbers! Thanks for clarifying. That said, taxonomic groupings can have both wide consensus and be useful, can't they? (Hand on chin... monotremes? hominids??)

Although if you want to get get technical, even evolutionary relationships are only trees if you throw out some of the information that doesn't fit the tree. It's truer to speak of phylogenetic networks that can take into account things such as horizontal transfer of genes and recombination.

https://en.wikipedia.org/wiki/Phylogenetic_network

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