Bitcoin Forum
May 05, 2024, 07:12:37 AM *
News: Latest Bitcoin Core release: 27.0 [Torrent]
 
   Home   Help Search Login Register More  
Pages: « 1 ... 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 [95] 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 ... 170 »
  Print  
Author Topic: Tau-Chain and Agoras Official Thread: Generalized P2P Network  (Read 309537 times)
sotisoti
Hero Member
*****
Offline Offline

Activity: 762
Merit: 500


View Profile
June 06, 2017, 12:56:17 PM
 #1881

Is the new whitepaper out yet?

Bitrated user: sotisoti.
If you see garbage posts (off-topic, trolling, spam, no point, etc.), use the "report to moderator" links. All reports are investigated, though you will rarely be contacted about your reports.
Advertised sites are not endorsed by the Bitcoin Forum. They may be unsafe, untrustworthy, or illegal in your jurisdiction.
1714893157
Hero Member
*
Offline Offline

Posts: 1714893157

View Profile Personal Message (Offline)

Ignore
1714893157
Reply with quote  #2

1714893157
Report to moderator
1714893157
Hero Member
*
Offline Offline

Posts: 1714893157

View Profile Personal Message (Offline)

Ignore
1714893157
Reply with quote  #2

1714893157
Report to moderator
mightyMight
Member
**
Offline Offline

Activity: 73
Merit: 10


View Profile
June 06, 2017, 03:53:25 PM
 #1882

Is the new whitepaper out yet?
when was it announced? is it the one the discussion was about recently, not to publish it right now to not have copycats?
PeytonItemu
Newbie
*
Offline Offline

Activity: 39
Merit: 0


View Profile
June 06, 2017, 05:40:39 PM
 #1883

2.5 years since the posting of this project is what im seeing
its nearly the launch?
new looking at the projects, looks very good...
digiguy
Full Member
***
Offline Offline

Activity: 160
Merit: 100


View Profile
June 06, 2017, 08:00:03 PM
 #1884

im buying a shit load of this coin looks very cheap  Grin Grin
Cibervision
Newbie
*
Offline Offline

Activity: 42
Merit: 0


View Profile
June 06, 2017, 11:09:33 PM
 #1885

Ohad can you tell us some news ?, are you work fine? , any bottle neck in the proyect?, the graphic/web designer Can do a tauchain infographic? ( i now he waiting for the content )  Are somebody or an agency doing the marketing plan.?. Any example for bounty? Many of us will be happy to go about doing things for Tauchain and by the way getting agoras.
ohad (OP)
Hero Member
*****
Offline Offline

Activity: 897
Merit: 1000

http://idni.org


View Profile WWW
June 06, 2017, 11:32:26 PM
 #1886

Ohad can you tell us some news ?, are you work fine? , any bottle neck in the proyect?, the graphic/web designer Can do a tauchain infographic? ( i now he waiting for the content )  Are somebody or an agency doing the marketing plan.?. Any example for bounty? Many of us will be happy to go about doing things for Tauchain and by the way getting agoras.


everything is very good, little flooded in the last week but that's just good news. our web designer & graphics guy works with me almost every day in my home.

Tau-Chain & Agoras
Foerster
Full Member
***
Offline Offline

Activity: 143
Merit: 100


View Profile
June 06, 2017, 11:54:47 PM
 #1887

Definitely one of the most interesting projects. The main question is if it can be pulled off or not with given resources and competition.
The slow progress literally forced me to put money into competitors.
However, I might invest some the galactic profits back to multiply my old Agoras holdings.
LiskEnterprise
Sr. Member
****
Offline Offline

Activity: 268
Merit: 250


View Profile
June 07, 2017, 09:01:37 AM
 #1888

Hi All,

Am i correct to say this is a $15,000,000 market cap project started in Feb 2015?

It has one dev and no whitepaper yet?

This is a strange project based on a few youtube interviews?

Am i missing something? A demo somewhere?

http://heatledger.com LIVE ICO 3.0 GENERATION CRYPTO WITH COMPANY STOCK IPO OPTIONS
ohad (OP)
Hero Member
*****
Offline Offline

Activity: 897
Merit: 1000

http://idni.org


View Profile WWW
June 07, 2017, 09:03:28 AM
 #1889

Hi All,

Am i correct to say this is a $15,000,000 market cap project started in Feb 2015?

It has one dev and no whitepaper yet?

This is a strange project based on a few youtube interviews?

Am i missing something? A demo somewhere?

there is a whitepaper (http://tauchain.org/tauchain.pdf) and plenty of code and materials (cf eg idni.org or github.com/naturalog/tauchain).
just the design was changed due to a mistake found (as published in the article "tau and the cirsis of truth"), so we have to write a new whitepaper, much enhanced this time.

Tau-Chain & Agoras
LiskEnterprise
Sr. Member
****
Offline Offline

Activity: 268
Merit: 250


View Profile
June 07, 2017, 11:44:48 AM
 #1890

Thanks for the reply as i understand it at the basic you are creating a logic non turing complete programming language that is general purpose.

How does it relate in logic to Shen, http://shenlanguage.org/

Forerunner is QI - http://www.shenlanguage.org/lambdassociates/htdocs/Book/page012.htm

thanks

http://heatledger.com LIVE ICO 3.0 GENERATION CRYPTO WITH COMPANY STOCK IPO OPTIONS
ohad (OP)
Hero Member
*****
Offline Offline

Activity: 897
Merit: 1000

http://idni.org


View Profile WWW
June 07, 2017, 11:48:50 AM
 #1891

Thanks for the reply as i understand it at the basic you are creating a logic non turing complete programming language that is general purpose.

How does it relate in logic to Shen, http://shenlanguage.org/

thanks

indeed a lot of similarities at the language level (as well as differences). however we take another step forward towards a logical discussion platform, and from there a discussion about the platform itself (self-amendment). in quite accurate and broad summary: tau is a large-scale discussion about tau. with all we see as required to make it happen.

Tau-Chain & Agoras
whyknot
Newbie
*
Offline Offline

Activity: 7
Merit: 0


View Profile
June 07, 2017, 03:38:04 PM
 #1892

Hello Ohad, the EOS white paper is out. It will actually start with WREN as a smart contract Scripting langage, but will be able to support others. Would it be appropriate to think that the EOS blockchain would be a better candidate for Tau than creating a specific (agoras) blockchain?
HunterMinerCrafter
Sr. Member
****
Offline Offline

Activity: 434
Merit: 250


View Profile
June 07, 2017, 04:39:44 PM
 #1893

Thanks for the reply as i understand it at the basic you are creating a logic non turing complete programming language that is general purpose.

How does it relate in logic to Shen, http://shenlanguage.org/

thanks

indeed a lot of similarities at the language level (as well as differences). however we take another step forward towards a logical discussion platform, and from there a discussion about the platform itself (self-amendment). in quite accurate and broad summary: tau is a large-scale discussion about tau. with all we see as required to make it happen.

Shen (Qi II) is CLOS under MLTT and so is much closer to the language of AutoNomic than of newtau, no?
eB101
Full Member
***
Offline Offline

Activity: 132
Merit: 100


View Profile
June 07, 2017, 08:28:49 PM
 #1894

hey Ohad, are you still selling? Seems like I can't get a hold of you via PM, so just making sure, though I know you must have full inbox.
mightyMight
Member
**
Offline Offline

Activity: 73
Merit: 10


View Profile
June 07, 2017, 08:33:02 PM
 #1895

Thanks for the reply as i understand it at the basic you are creating a logic non turing complete programming language that is general purpose.

How does it relate in logic to Shen, http://shenlanguage.org/

thanks

indeed a lot of similarities at the language level (as well as differences). however we take another step forward towards a logical discussion platform, and from there a discussion about the platform itself (self-amendment). in quite accurate and broad summary: tau is a large-scale discussion about tau. with all we see as required to make it happen.

Shen (Qi II) is CLOS under MLTT and so is much closer to the language of AutoNomic than of newtau, no?
I read now several times about 'Autonomic' and understood this is some sort of other project or fork. But a simple search brings always up Tau. Does this other project exist?
mightyMight
Member
**
Offline Offline

Activity: 73
Merit: 10


View Profile
June 07, 2017, 08:48:31 PM
 #1896

Hello Ohad, the EOS white paper is out. It will actually start with WREN as a smart contract Scripting langage, but will be able to support others. Would it be appropriate to think that the EOS blockchain would be a better candidate for Tau than creating a specific (agoras) blockchain?
Intersting a whole operating system for that. What i can see right now is they got a github with EOS and a docker folder. So this runs on *nix and says its written in c++. In sense of security, stability etc wouldnt it be a better choice to build it in some functional programming language?
statdude
Legendary
*
Offline Offline

Activity: 1498
Merit: 1000


View Profile
June 07, 2017, 09:21:30 PM
 #1897

Whats better price, market or Ohad ATM?

▄█▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀█▄
█ ███████████████████████ █
█ █████     █ ▀██████████ █
█ █████     █   ▀████████ █
█ █████  ██ █     ▀██████ █

█ █████  ▀▀ █▄▄▄▄▄▄▄█████ █
█ █████  ▄▄▄▄▄▄▄▄▄  █████ █
█ █████  ▄▄▄▄▄▄▄▄▄  █████ █
█ █████  ▄▄▄▄▄▄▄▄▄  █████ █
█ █████  ▄▄▄▄▄▄▄▄▄  █████ █
█ █████             █████ █
█ ███████████████████████ █
▀█▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄█▀
  Website
    Twitter
      Gitlab
      Reddit
    Telegram
Whitepaper
  ▄█▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀█▄
█ ███████████████████████ █
█ ███████████████████████ █
█ ███▄    ███████▀   ▄███ █
█ ████▌    █████▀    ████ █
█ ████▌     ███▀     ████ █
█ ████▌▐█    █▀ █    ████ █
█ ████▌▐██     ██    ████ █
█ ████▌▐███   ███    ████ █
█ ███▀  ▀███ ███▀    ▀███ █
█ ███████████████████████ █
█ ███████████████████████ █
▀█▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄▄█▀
whyknot
Newbie
*
Offline Offline

Activity: 7
Merit: 0


View Profile
June 07, 2017, 10:07:38 PM
 #1898

Hello Ohad, the EOS white paper is out. It will actually start with WREN as a smart contract Scripting langage, but will be able to support others. Would it be appropriate to think that the EOS blockchain would be a better candidate for Tau than creating a specific (agoras) blockchain?
Intersting a whole operating system for that. What i can see right now is they got a github with EOS and a docker folder. So this runs on *nix and says its written in c++. In sense of security, stability etc wouldnt it be a better choice to build it in some functional programming language?
EOS is a generalisation of bitshares / steem and use the same proven methodology (C++, graphene, Delegate POS, ...). It is like a back end blockchain engine (operating system), on top of which you can create apps (smart contracts, currencies, exchanges). Would be nice to have Tau Apps running on it.
LiskEnterprise
Sr. Member
****
Offline Offline

Activity: 268
Merit: 250


View Profile
June 07, 2017, 11:43:58 PM
 #1899

This is all interesting..

Just to rehash this....

After time has passed is opinions the same?

Has there been a closing of the gap with disagreements or are opinions still varied?




Can you clarify which part of this post you do not agree on so that maybe you can have a public discussion with Ohad about this? I hope that a public discussion on the ideas and concept is welcomed and can benefit Tau design at the end.


We have already had significant public discussion in the IRC channel, which did not lead to any resolutions, but I will still summarize the state of affairs here for you.

Quote
MLTT does not have decidable typecheck in general.

While technically true for general MLTT, it is not a problem in practice in an MLTT TFPL, particularly for tau.  If it were generally a problem, languages like agda/idris would not be particularly useful for verified programming.  In the (few, largely meta-theoretical) cases where this does significantly complicate proofs in practice, postulates can be used to sidestep the problems/complexities.  (This was the approach wrt "tau classic" design as well, community-agreed postulate rules within contexts.)

Quote
But it is not the case that everything expressible is decidable.
If you restrict "expressible" to exclude meta-theoretic propositions, partial propositions, and non-productive propositions (again, as agda/idris do) this statement is simply false.

Quote
This situation led me to a conclusion that MLTT was a wrong choice, and another logic should be considered.

OK, let's assume he were right, and MLTT was somehow not suitable - for the sake of answering your actual question of what the problems with the proposed alternative are seen to be.....

Quote
The remedy for this situation is to pick a different logic, a "complete" one.

As we (the non-Ohad "team" members) see it, tau (classic) necessitates a "computationally complete" language.  We believe this is the case due to the problem statement itself: a fully generalized decentralized network.  In order to be "general" the logic of the network needs to be able to "compute any computable function" in the processing of its rules, as otherwise you restrict the set of possible rules that the network can employ, and lose generality.  Because tau also necessitates consistency (I don't think anyone will argue that point) the requirement of a computationally complete language would imply the necessity of a logically *incomplete* language.  This is largely the central "dispute" between Ohad and the rest of the "team" at this time.

Let's go on to see what alternative logic he did choose, though, to see the "lesser point of contention"...

Quote
Specifically, certain classes of Monadic Second Order Logic (MSO or MSOL) were found to be complete and consistent since the 1960s, but they did not have satisfactory expressiveness abilities.

The expressiveness of MSO is the specific concern.  We do not (even after months of researching and discussion as to if Ohad "might be right") see how the "self defining nomic" that is tau can be expressed in MSO.  Specifically, we believe that such an expression necessitates general algebraic data types, which MSO can not express.  Ohad will be the first to tell you that MSO omits multiplication, but what he seems to overlook is that it also omits "general products" which significantly limits the ability to even express something like a blockchain, let alone a tau.

Quote
To mention three advantages: the existence of a direct computational model, the ability to infer programs, and simplicity of use.

The rest of the "team" actually got "luls for days" out of this line.  MLTT has a computational model, has a term inference procedure, and is only slightly harder to use than, say, Haskell or OCaml.  If these things were not the case then the MLTT programming languages and proof systems simply would not be.  As it is, they not only are, but are the most common and popular form of verified programming today.

Quote
It cannot possibly exist since automatons are an explicit finite decision procedure, while dependent types are not completely decidable.

Again, true of general MLTT but not true of an MLTT TFPL, which omits metatheoretic, partial, and non-productive expressions.  Such a language does have a direct automata translation, which is even employed in the "backends" of some MLTT based systems for efficient code generation.

Quote
This task is undecidable on MLTT

Actually, it is "semi-decidable"....

Quote
We can have correct-by-construction programs and contracts, by merely stating what we expect them to do, and commanding the machine to find such a structure that admits our requirements.

Being semi-decidable, an MLTT TFPL can employ this as well.  The only difference is that instead of being a strict decision procedure, it will come back with either a program, a proof of impossibility of the program, or a question about a refinement to our specification.  After a finite number of such questions, it will come back with either a program or a proof of impossibility.  As term inference is an "offline" process in tau usage, this semi-decidability is acceptable.

Quote
MSO logic is simpler to use for the reasons mentioned above: it is a simpler language, and does not require human intervention to convince that a true statement is true indeed.

I don't see MSO as particularly "simpler," myself.  Further, given an "already expressed" proposition and its proof, no human intervention is required to convince an MLTT framework of it, either.  These statements seems entirely disconnected, and do not really follow from the prior line of reasoning.  Which is "simpler" is subjective and debatable. Also, in *any* type system, something that passes typecheck passes typecheck, so I'm not sure what is really trying to be said on this latter point.

Quote
It also represents a more intuitive logic:

Whether classical or constructivist logic is "more intuitive" is a highly subjective matter.  Personally, I find them rather equally intuitive.  I've also spoken to people who reject classical outright as non-intuitive, and people who reject intuitionistic outright as non-intuitive.

Quote
More formally, intuitionistic logic explicitly negates the law of excluded middle.

Erm, no.  It does not have "not (p or (not p))" as an axiom, as this statement would suggest.

Quote
And this is of course highly unintuitive, and allows the possibility of human mistakes especially over complicated structures.

I'm not sure what this is intended to mean.  Although "LEM" is not axiomatic in MLTT, neither is its negation, so it can always be assumed as a lemma for any given proposition.

Quote
On the other hand, MSO is a Classical logic, means it includes the law of excluded middle: it's simply impossible for anything to be both true and false at the same time.

Being consistent, this is also impossible under MLTT, of course.

Quote
The middle is completely excluded, while if we add this rule to MLTT, it loses its consistency.

MLTT only loses consistency if LEM is included as axiomatic. LEM can be freely applied over any proposition, otherwise.  This is generally so well understood as a "basic concept" in the intuitionistic logic that Ohad's apparent misunderstanding of it has led some of us (myself and stoop, in particular) to question some of Ohad's grasp of the fundamentals of constructive intuitionistic logic, in the first place.  (I'm particularly baffled as to how he can seemingly grasp Glivenko and the Godel-Gentzen negative translation, but cannot grasp the simple matter of the usage of LEM in MLTT.... it seems to me that to understand the one means to understand the other.....)

IN SUMMARY:
The first part of this argument is not really "new" or unique to tau's situation.  The question of "general suitability" of intuitionistic logic goes back to the 1920s.  I doubt that we will resolve this debate, but suffice to say that Ohad is the only one from the "team" who believes that MLTT is unsuitable specifically for tau.

IMO, the second part of this argument is the much more central matter:  Can MSO be used to construct a tau at all.  Nobody else from the "team" seems to be even remotely convinced that it could, and everyone (Ohad included) seems to have a strong understanding and agreement that if it can (at least to some degree) then there is a necessary loss of generality in doing so, which means that the original goal of a fully generalized overlay network would not be able to be met by it.  (This latter point can be easily seen by the fact that MSO is a strict weakening relative to MLTT - anything provable in MSO is provable in MLTT, but the reverse is not true.  This means that there are some rules/topologies which could be enacted on tau classic which could not have parallels on mso tau.  We see this as a *big* concern.)




http://heatledger.com LIVE ICO 3.0 GENERATION CRYPTO WITH COMPANY STOCK IPO OPTIONS
LiskEnterprise
Sr. Member
****
Offline Offline

Activity: 268
Merit: 250


View Profile
June 08, 2017, 01:27:59 AM
 #1900

Another huge post with a lot of information...


Is this only resolvable with release of a White Paper or have discussions continued behind the scenes.

Is it correct on a project such as this it is better for an individual to write a new functional programming language as in SHEN

Or for a team as in Haskell?


@HMC, any further thoughts from you?

I had written up a response pretty quickly, but none of us were particularly thrilled with the tone or the length.  We deliberated for a while (mostly stoop and I) as to if and how to better structure it, and as to if we should even continue to engage this thread at all.

Here is where we've ended up.

Note: this reply includes comments from both myself and stoopkid.  I'll clearly distinguish stoop's responses from my own.  (He has reviewed this post, and given his nod of approval to its' content.)

Quote
you mix decidability with consistency.

Not at all, and I stand by my statement.  If agda/coq/idris et al had the particular properties that you claim they do then there would be cases where you could trivially send them off into an infinite loop in type-check/termination-check.  Developers in these languages would often be left wondering if their compiler was ever going to finish, or if it was stuck.  This would not be very practical, indeed.  Luckily, this  is nonsense and simply isn't the case, as they all employ decidable, impredicative, intensional type theory.  (Ofc there are also ITT TFPL systems which allow predicativity/extensionality (or even arbitrary rewrite) and are thus undecidable (even under a most conservative approximate) such as NuPRL or MetaMath's ITT.)

If you have an example of a known-terminating program which does loop the MLTT TFPL typecheck, despite termination check, as you describe (without using "type providers" or similar, anyway) then you should probably report it to the language developers as a bug, I'm sure they'd like to hear about it.  (Such bugs *do* get reported from time to time. For example the only currently known case in agda looks to be https://github.com/agda/agda/issues/1270 but these are *bugs* and treated as such, just as an inconsistency would be, meaning they are always rectified in the implementations.  To date no-one has broken the MLTT TFPL *theory* itself, thus rendering all implementations "loopable.")

(I'm still not entirely sure what it is that you're "missing" here about practicality of MLTT TFPL, but the best I can *suspect* is that it might be the fact that predicates can be internally proven decidable, and one can work solely in such decidable predicates when reasoning about any known terminating algorithm.)

Quote
proving correctness is another task that sometimes can be done without the language being decidable, but of course not always.

I've asked you many times for any example of any proven-terminating algorithm which cannot possibly be expressed and checked as such in agda/coq/etc.  You've been unable to produce one as of yet.  Until you can, I have to consider your claim of "of course not always" as nonsense.

Quote
see why people are not satisfied from dependent types (hint: mainly due to undecidability but also from being quite complex) and the mainstream is focused on modern methods (hint: msol).

More nonsense.  Nearly every "major" theorem prover in practical use today (Mizar being the notable exception, but then again it is arguably inconsistent by design) is based on dependent types, ITT, and MLTT specifically.  Outside of academic study, MSOL is, afaik, currently applied only in a few cases of bounded model checking, and virtually always in a hybrid solver.  (Meaning it is almost never used "alone" for general verification, as it would be of too little practical value.  Every solver I'm familiar with which uses MSO combines it with at *least* an SMT solver for integer arith.)

Further, nearly every contemporary type system being developed or added to existing languages for practical use is based on dependent refinements.  I don't see anyone adding MSO type systems to Scala or Rust, or working to build an "MSO Haskell" or "MSO Ocaml" or "MSO Java/C#"....  Are you aware of some such efforts that I'm not finding?  (There are such contemporary efforts to add dependent types to basically every popular language...)

Quote
the "few" cases (which are in fact infinitely many) might be enough for malicious players to harm or fool the network by making it unsound and unfair.

Nonsense.  The only way that this could happen is by a context choosing to adopt an unsound postulate, which would be akin to a context intentionally adopting rules for "stalling" their own chain, or going mao, or...  Yes, there are a lot of ways that a context can *choose* to harm/destroy itself.  This will remain true regardless of the logic employed.  It is not a sensible argument against MLTT for tau.

Quote
but again such restructure (the postulates) is not always possible

Epic nonsense.  A postulate is NOT a restructuring of a proof, it is an intentional, partial omission of one.  Further, a postulate may assert anything at all, even a direct inconsistency.  There is, of course, no proof which can not be immediately closed by assuming a postulate.

Quote
and is undecidable problem to show that restructuring maintains the original behavior (as functional extensionality is undecidable on mltt+tfpl).

Partly nonsense.  HoTT/univalence does give decidable function extensionality in MLTT.  However, this is beside the point entirely as postulates (and other inference-affecting annotations) are not a "restructuring" of a proof at all, they cannot affect the behavior of a program - only its typecheck.  (In other words, extensionality has nothing to do with it.)  They can explicitly *omit* some behavior of a program, but generally do not need to as they can be erasable.


Quote
if i restrict "expressible" to "not all expressibles", then sure..
"expressible" is about syntax. not every well-typed statement well-formed in agda/idris would pass typecheck. being "total" is not part of the syntax, for example. deciding which program is total and which isn't is of course an unsolvable problem in general. MLTT is undecidable, and restricting it to TFPL would be another undecidable task (as i explained in the blogpost).

Nonsense upon nonsense.  Such an expression restriction is precisely what agda/idris/coq/etc do, and they are entirely decidable TFPLs, that remain computationally complete.  Totality is not undecidable, in fact it is trivial.  (It is also syntactic, just "case alignment," but that is little to do with anything here.)  I think you must be confusing totality and termination/productivity here.  What they "punt" on is a case of termination/productivity check, not of totality.  Productivity check is undecidable in general.  However, by restricting the syntax to reject recursive predicates which can not be asserted terminating/productive by size-change termination arguments, it is kept decidable.  (Again, exactly what Agda/idris/coq/etc do.  For the specific termination check used in Agda, for example, see Abel's "A Predicative Analysis of Structural Recursion."  For an even more formal (and also somewhat more efficient, P-Space complete) treatment, which agda may or may not end up switching to, see Hyvernat's "The size-change termination principle for constructor based languages.")

Does this lead to any syntactic case pattern which must be rejected?  Yes: for example in agda the mutual co-recursion as described on their wiki, as we've discussed at length.  Does this mean they are not computationally complete, or that there are terminating algorithms which cannot be expressed and reasoned as terminating?  No!  Maybe you think that there is some terminating algorithm which cannot possibly be written without these particular "SCT-less" recursion patterns but, again, you have not been able to demonstrate one as asked.  (It seems to me that any such case could just be "loop unrolled" to remove the mutual recursion, since it is known terminating.....)

Even if you could possibly provide such an example, the given algorithm could still be made to be accepted in typecheck by way of a postulate assumption or explicit annotation.  (Or, similarly, if the termination were simply unknown, or "prohibitively difficult to prove," as might the case of your non-example "Collatz example.")

Quote
you answered nothing regarding the problems i mentioned on the blogpost about MLTT or MLTT+TFPL.

I didn't?  It sure seems like I did...  All well, agree to disagree, or whatever.  Let's move on.

Quote
tau is required to be decidable.

I'm not so sure why this would be (as tau would need all proofs to be bounded to some "reasonable" size constraint, anyway... for practical purposes there is little difference between an infinite derivation and one that takes 1000 years to evaluate on contemporary hardware) but it is a moot point unless you can demonstrate a practical decidability problem by showing a case where the MLTT TFPL typecheck would necessarily loop infinitely over a terminating algorithm.  (There aren't any... so I'm guessing I'm likely to be continuing to wait for this for quite some time.)

Quote
this, even though msol over lambdas does not restrict expressiveness more than mltt+tfpl if assuming infinite blockchain, as you assume in your claim that mltt+tfpl is computationally complete.

Quote
MLTT+TFPL is not computationally complete.

Most epic nonsense.  I'm also not so sure that you understand what "computational completeness" means.  MLTT is computationally complete, even without an outer loop.  What is recovered by the "infinite blockchain" model is *Turing* completeness.  These are not the same thing, as you should certainly understand by now.  (Otherwise this is just more indication that you are certainly a long way away from being ready to build a tau, with any logic.)

MLTT (w/ or w/out TFPL constraints) is computationally complete - there is no boolean computable function which it cannot express, typecheck, and extract a (necessarily terminating) program for.  Maybe it is the meaning of "computable function" that you are confused about?  These are the boolean functions that "finite turing machines" can compute, in finite time/space resource.  (Finite turing completeness is and always was the goal.)

Your "complete and consistent" MSO is (necessarily) not computationally complete.  It is simply not possible to have a complete, consistent logic which is also computationally complete, as being computationally complete implies being able to express and reason over full arithmetic axioms.  Any logic which is both consistent and computationally complete will necessarily be incomplete.

Quote
no total language is computationally complete, as it can never interpret itself.

Double nonsense.  Self-interpretation is not a requirement for computational completeness.  Even if it were, your argument still doesn't stand up as total languages *can* self interpret (contrary to conventional wisdom) as established recently by Brown-Palsberg.  (Why you'd even make this claim is strange, since both Brown-Palsberg's self interpretation and Bauer's self interpreter for System T were discussed several times on the IRC....)

Note from stoopkid: "the conventional proof only says that there can be no total computable universal function for the total computable functions, and that any such universal function must be strictly partial, but that if a rewrite system is strongly normalizing then it necessarily cannot be this universal function, because a strongly normalizing rewrite system is equivalent to some total function, not any strictly partial function, and thus can't be a universal function for the total computable numbers, so the conventional diagonalization proof doesnt say anything about the expressibility of the total functions defining strongly normalizing rewrite systems in regards to whether or not they can be their own universal function which corresponds to not saying anything about the existence of self-interpreters in strongly normalizing rewrite systems."


Quote
therefore in some aspects is way more generalized than mltt+tfpl (not strict generalization ofc), yet it is decidable.

Nonsense.  MSO is strictly weaker, as it is entirely and directly expressible in MLTT.  Anything that can be expressed and proven in MSO can be expressed and proven in MLTT.  The reverse is not the case.  To call MSO "more general" exhibits a misunderstanding of *both* MSO and MLTT, and even of logic and the computable hierarchy in general.

Quote
aside ignoring the rest of the paragraph on that blogpost where i mention a way more expressive msol (as a little example, regular trees can express all context free deritvion trees, while even second order recursion trees are context sensitive), i never saw even a small trial of you to reach it. in fact i never saw you studying msol seriously.

Perhaps the reason you never "saw" could be because you drove all of your "team" into another channel, where we continue discussion without you...

Quote
"there is no msol design for X" means that design should be done. you can't expect modern theories to be as developed as obsolete theories.  simply stating "it's impossible" is not my way of work.

Great, so go get to it.... it has actually been many (>6) months, now, since you originally decided MLTT isn't the way, and we haven't seen even the beginnings of an explanation of your design of an alternative. (Or any other new work on your part, since, for that matter...)

Quote
that'd be a groundbreaking result. can you prove it?

I'm not sure how this would be considered "groundbreaking."  It is quite straightforward to see that a block is defined as a product of hashes....

Quote
haha no. in fact even the so-restricted regular trees can do quite much of arithmetic with add and mul, as can be seen here https://staff.aist.go.jp/hitoshi.ohsaki/papers/kobayashi-ohsaki-rta08-fullpaper.pdf

Silly nonsense.  (Sometimes I wonder if you even read the papers that you link.)  Linear inequality of multiplication against a *constant* value does not make for a theory of multiplication.  It is an extension of addition.  (Multiplication by a constant is, of course, just iterated addition.)  Further, the logic employed to establish this limited multiplication in that paper is not even MSO but is "monotone AC-TA."  This adds to my perpetual suspicion that when you say "MSO" you don't really mean "MSO" but "something else..."  Some "other" logic that you have in your head, but can't yet seem to name, describe, or even assert the actual existence of.

Of course it would be self-contradictory for you to claim that multiplication is possible in your hypothetical complete & consistent "somehow MSO-like but not really MSO" logic.  As you rightly elaborate in your blog post, this would contradict Godel.  If tau is to be built with a complete and consistent logic, then it will necessarily omit some portion of basic arithmetic - meaning there will be some math which it *cannot* do in its rules - meaning there will be some routing/topology rules which it *cannot* employ - meaning it will *not* meet the original goal of a fully general, decentralized network.  (This is inescapable without accepting an incomplete logic.)

Quote
no idea which kind of product you lack here (that say intersection types cannot give),

If you don't know what a general product is, (and why GADTs are important for programming in a typed functional setting) or the difference between a product type and an intersection type, then you are certainly still a *long* way (another year or two, maybe?) from being ready to build a tau, using *any* logic.

Note from stoop: "you might explain why exactly MSO prevents the definability of the general product, even without appeal to godel; mso rules out quantification over functions of arity greater than 1, but the product of two types A and B is equivalent to the polymorphic type Pi C:* . (A -> B -> C) -> C which explicitly requires quantification over that binary relation in order to form it, and since this is just an almost trivial example of a GADT it's got no chance there. btw i'm curious if parametricity results can prove that you need quantification over a binary function in order to express the general product."

(I won't bother explaining this more than he already did, as any further detail can be readily googled up.)


Quote
and why you're so convinced there's only one way to implement a blockchain.

I never claimed that there is only one way to implement a blockchain.  I do claim that any way to build a functional, self-defining blockchain seems to require GADTs.  (Do you have a way to define a block validity function that does not have a domain of block headers which are products of hashes?  I'd be very interested to see that!  *That* would be "groundbreaking." Grin)

Quote
well then many of contemporary cs literature can provide you plenty of entertainment, as those three are mentioned in many places.

So the computational model of Agda doesn't actually exist, and the native compiler is just smoke-and-mirrors?  The hole-filling term inference of Agda and its nice emacs interface are also an illusion?  These tools, which are so easy and approachable that they've been compared to the interface of video games (quite an accomplishment for such a complex software) are somehow actually much less usable than they seem?  Nonsense, nonsense, and nonsense.

Quote
the old ways are popular indeed in practice (though i wouldnt say *most* common and popular), but are only the old ways, and now we have new ways that people invented for very good reasons.

Let's just ignore the fact that MSO predated MLTT by quite a bit, and is certainly well set in "the old ways" of the days of Frege and Quine...

MLTT was invented for a "good reason" too: specifically to establish a computationally complete, yet consistent logic.

Quote
as a small quote i'll paste from the beginning of
Quote
However, they often
require explicit type annotations (as in dependent type systems), or suffer from
many false alarms.

Personally I'll take a need to explicate types over a lack of general arithmetic/computation any day.

Quote
just getting from mltt to mltt+tfpl would require a possibly infinite procedure....

Someone should really let the agda/coq devs know... XD  I don't think that they're aware that they've been doing the impossible this whole time...

Quote
all undecidability problems of computation are in general only semi-undecidable, as Hilbert's 10th problem is semi-decidable.

Sure, but this doesn't change the fact that this case of (semi/un/partial)-decidability is irrelevant, as it is an offline, user-interactive process and not a part of the network consensus process.

Quote
that's simply not true. it can happen some times, but it's impossible for this to happen all the time.

OK, so now I have two examples to request of you!  Can you give an example of a hole in a known-terminating program specification which cannot be filled in finite interactivity steps by the agda hole-filler?

Until you can demonstrate an example fitting this claim, I have to assume that it is nonsense as well.

Quote
msol is much simpler as it contains much less primitives and decision procedures are fully automatic. claiming otherwise would be either misleading or baffling misunderstanding. is might not be simpler for you but that's only because you're still beginner in msol while somehow experienced with mltt. it's not a matter of taste, mltt (far to mention mltt+tfpl) is way more complex than msol over lambdas, it's just a fact.

Again, I guess we'll just have to agree to disagree on this one.  As I see it, any question of what is "simpler" or "more intuitive" is necessarily subjective, but we seem to have a difference of opinion on that.

I, personally, see MLTT as "simpler" because it is like the "yodawg of lambdas."  If you understand lambda calculus then you already understand everything about MLTT except cumulativity.  It's the very same abstraction/application, just done at a type level language instead of the term/object language of the program itself.  It puts the same beta/eta applicative reduction in the type theory as is in the object language.

If you can grok lisp/scheme then you can grok MLTT.  In fact, you basically already know it modulo the impredicative universe hierarchy.

With your hypothetical MSO/TA higher-order model framework it seems that one needs to learn not only the lambda calculus, but also FOPL, some general monadic logic, some set theory, some TA theory, some iterative TA theory, some graph theory, and you'd better know some modular congruence properties and Courcelle theoreom and Seese if you want to do any application at all, and Kobayashi and Ong if you want to do any contemporary, practical application at all... and then odds are where you end up at after all that study you still probably aren't equipped to know how to assert anything but the most basic correctness and reachability properties.... if that.

While I understand that the MSO logics might seem simpler at first glance, and might "sell better," by being just a classical logic, the reality of pragmatic application to "programming in the large" is very much a different story.

You've been studying these logics for ~6 months now, yourself?  Can you show some of the proofs that you've written with them so that we can get an idea of your own level of sophistication in actually using the logics after this dedicated study?  (Are you prepared, yet, to give even a simple proof or still "learning it" to get to that point, yourself?)

Note from Stoop: "he's been studying these systems 6 months and isn't proving anything in them, you should point out that we're now routinely building formalized propositions and verified programs and doing things like proofs of the uncountability of the reals and playing with GADTs and all kinds of other fun things that MSO can't even do, and that tau will come pretty much right away with general computability theory & theoretical comp sci libraries, and related results formalized and ready to work interoperably to aid in chain development, and that we're actually at the point of seriously examining how to actually put together a nomic block-chain in this system." ...  "you might also note that everybody on our team probably has a better understanding of MSO than he does at this point. since we understand it completely fully as just a specific and not very expressive subset of MLTT. and are seeing a more complete picture that illuminates exactly why MSO has the specific properties it does and how those actually relate to the rest of MLTT."

In my experience, most programmers (even "low/entry level") can pick up the basics of MLTT to the point where they can prove over simple-but-useful programs in under a week of dedicated study.  If they're experienced with functional languages (like lisp/scheme) beforehand it is usually more along the lines of 1-2 days of tinkering.  If they're familiar with pure, statically typed functional languages (like haskell/ocaml) it is usually a matter of hours.

Quote
vast majority of mathematicians and philosophers find the intuitionistic approach unintuitive. indeed there is a tiny minority of people thinking otherwise, but to picture it like it's a "matter of taste" would be a misrepresentation.

Nonsense.  The "vast majority" of real mathematicians/philosophers understand that there are trade-offs, and that they are best served by studying both.  Considering that it is a century-old and still unresolved debate, I don't think you can claim that it can stand as anything but a "matter of taste" in general.  Some mathematicians work in areas where constructivisim is *strictly* necessary, some mathematicians work in areas where classical sets bring ease, and some work in meta-theory where they're required to understand both intimately.  To claim that the "vast majority" reject intuitionism just indicates to me that you haven't spent much time actually talking with many of them.

Quote
is not an axiom but follows from the axioms in few steps. is in the literature all over....

More nonsense.  I can't even...

Can you show any constructive proposition at all for which it cannot be applied?  (If you can, you've invalidated Glivenko and Brouwer both, no?)

I think what you meant to say was that "not not (p or (not p))" follows in a few steps.  (Again, per Glivenko! (1928))

(Side note: interested on-lookers should be encouraged to read http://plato.stanford.edu/entries/intuitionistic-logic-development/#2.4 for a nice summary explanation of these concepts.)

Quote
and this is unintuitive. i never said LEM cannot be worked-around (except in proving existence by contradiction). i said it is unintuitive and by that more prone to human errors.

I am not sure what you find "unintuitive" about it, but again that is a subjective matter.  We'll agree to disagree.

I don't see any case in which it would be "more prone to human errors" however.  After all, we are talking about theorem provers, in which precluding human error is "the whole point."  Could you clarify?

Quote
it is impossible to prove a statement to be both true and false under mltt, as it is consistent indeed, but, proving that a statement is false, doesn't amount as a proof that it's negation is true, in mltt. in classical logic things are either true or false, exclusively.

While I agree that in MLTT a statement can not always simply be negated to prove the inverse, this doesn't imply that things are not "either true or false, exclusively" in MLTT.

Of course everything in MLTT is "either true or false, exclusively."  As you just stated yourself, it is consistent.

Quote
just like human intuition works when it comes to formalism. and just like the vast majority of mathematicians in all eras hold.

Our intuition must certainly work differently.  That is OK.  "Agree to disagree" and all.

As to how the "vast majority" of intuitions work, I won't be so arrogant as to assume.... and I don't think that there's been anything like a census...  Feel free to show some statistics on the matter, however, if you know of such a poll!

Quote
sure. and this should give you some clues regarding the incapability of mltt to ultimately support LEM.

Not at all, and I'm not sure why you'd think it would.  Can you give some example or explanation of an "incapability" of MLTT to "ultimately support LEM?"

Quote
no, not "any", otherwise it could be added as an axiom.

Nonsense.  So I'll ask for a third demonstration from you, can you give me any true, constructive proposition for which LEM as a lemma does not hold in MLTT?

(Fun facts for the astute reader: Note that such a lemma will have as codomain a disjunct of the proposition P and P->_|_ so for any true proposition "inl" holds and for any false proposition "inr" holds.  Being able to show such an example where a LEM lemma could not be applicable would actually require violating LEM by modifying the logic to be 3-valued, which is what justifies LEM as sound (for either classical axiom or intuitionistic proposition) in the first place!  (Hence the name...)

The reason (I'm drastically paraphrasing) that it can not be taken as axiomatic in MLTT without violating consistency is that it would then also have to apply over the top of the universe hierarchy, which would create an infinite regress and prevent closure.  (The cumulative hierarchy could then have no "top" and you're back in the "type in type" or "kind-inconsistency" situation.) The reason it can be applied over any predicate without violating consistency is that there is syntactically no way to apply it over the largest universe, without also implying a larger universe (which it is not applied over) in doing so.

This has some fascinating implications, the most basic of which is that "(P or (not P)) -> ((not not P) -> P)" is trivially provable constructively, but the inverse "((not not P) -> P) -> (P or (not P))" does not hold in general... (I think that this is probably what Ohad is actually trying to point out wrt his statements on proof by contradiction... but who knows) however if we quantify both sides of the inverse implication we can prove that if for all X "(((not not X) -> X)" holds then this implies that for all X "(X or (not X)))" does as well! Wink  I'll leave these (quite informative!) proofs as an exercise for the reader.)

Also, here is a "haskeller level" proof that LEM is intuitionistically sound that you should have no trouble to follow: http://okmij.org/ftp/Computation/lem.html

They go on to prove the existence of the number 42 by contradiction (strong reductio) and close "We have thus confirmed the old result that LEM is intuitionistically justified for decidable propositions."

... An "old result" indeed.  I'm not sure why you would deny it!

Quote
the double negation translation shows equi-provability, but my argument regarding LEM was about being intuitive. one could complexify-for-nothing say msol to become intuitionistic via double negation, but one cannot fix mltt to be classic, at least no one yet.

You're not wrong.  (Well, maybe you're wrong about what is/isn't intuitive, but we're agreeing to disagree on that, still.  There's probably no way to establish that definitively, short of a census, anyway.)  MSO could be double-negation-transformed into ITT.  You're especially not wrong that this would be particularly "for-nothing" given that it can also be transformed directly in the positive, as well.

In fact, this is largely the least nonsensical thing that you've said here.

However, you're missing the point entirely!  The double-negation transform wouldn't hold in general if it weren't the case that LEM could always be applied.  (Maybe you should try working those 2 "exercise" proofs in that I just mentioned in ITT if you don't understand this...)


Quote
being classic vs intuitionistic logic was only one practical advantage i mentioned of msol vs mltt. it has nothing to do with the core of my arguments.

(I'm not sure why it is a "practical advantage" exactly... Can you clarify?)

Sure, the core of your (first) argument is "ITT/MLTT won't work" but you've yet to actually give any demonstration of evidence justifying any of the reasoning behind it.  Instead you just make obviously-misguided claims about agda/coq/idris/etc which can be empirically dismissed by just "trying it at home" in agda/coq/idris/etc.... but you refuse to "try it at home" and then you purport it as justification for MLTT not working for a tau.  There may be no bigger nonsense than speaking the opposite of testable fact.

Quote
no decidable logic (including mltt+tfpl) was shown so far, rigorously, to support nomic game.

Nonsense.  There are nomics in haskell, nomics in deontic logic, nomics in Drools rules, nomics in coq (predicative CIC derived from MLTT TFPL!), nomics in LKIF (which is expressible in a fragment of owl which is in turn expressible in MLTT TFPL!), nomics in relational algebra (also expressible in MLTT TFPL!), nomics in M$ Excel (the logic of which is probably expressible in MLTT, why not?)..... all of these are decidable frameworks supporting nomic games.  Again you're simply making statements that are contrary to fact.


Quote
you ask for something that you yourself didn't provide. and it requires work in which for your own reasons you refuse to do. still this is what i work on and i encountered that one cannot have a sound nomic game under mltt+tfpl.

You "encountered" this, but can not adequately demonstrate or even explain it?

Quote
you're welcome to move into rigorousity rather handwaving and basis-less claims and present a design of a sound tau based on mltt+tfpl.

I'd be willing to bet that a "sound MLTT tau" will emerge before you even finish defining and implementing your still-entirely-hypothetical-but-somehow-"MSO-like" logic for your "better" design. :|

Quote
in summary, you didnt answer to any of the concerns i raised about mltt+tfpl, and you didnt present any reason why msol over lambdas is not good enough for tau.

NONSENSE.  I've stated our position quite clearly, and completely.  (Also, now, repeatedly.)

Quote
your reply contained so many blatant and subtle mistakes, so apologies if i didn't cover them all on this reply

If you feel we are incorrect, please prove it.  (It is all that I or anyone else has ever asked of you)  Wink  Implement your MSO tau, and destroy our MLTT tau.  We all wish you nothing but the best of luck in both endeavors, but I currently have nothing but skepticism that you will (or even can) accomplish either.


Quote
you're welcome to give a much more professional response to the blogpost.

I think that I'm, personally, just about done with wasting my time in responding to your nonsense.  My post was not in response to your blog post (else you would've seen it some time ago) it was in response to a specific request from your community to clarify the position of your lost "team" as most of your community were not privy to our initial reaction to your nonsense in the IRC.

If you feel it was unprofessional of me to answer your community's request for an explanation of our perspective, then I apologize.  I can refrain from polluting their perception with our reality in the future.

Quote
don't expect people to accept any statement that contains technical words.

Wut?

My apologies, also, for putting faith in your community's ability to comprehend my "technical words" if they choose to.  I'm also quite sorry that you don't have, as I do, confidence in their abilities to understand (or, at least, learn) what we are talking about.

Stoopkid also asked that I mention that we are actively working on putting together introductory materials to explain "tau classic" from first principles, aimed at those without math/programming experience.

(Anyone who can speak a language has the innate ability to grasp logic, so this is just more of your nonsense.)



http://heatledger.com LIVE ICO 3.0 GENERATION CRYPTO WITH COMPANY STOCK IPO OPTIONS
Pages: « 1 ... 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 [95] 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 ... 170 »
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.19 | SMF © 2006-2009, Simple Machines Valid XHTML 1.0! Valid CSS!