HDTenEightyP/NetNews huggingface dataset:
From: Christopher_C_Lapp@cup.portal.com
Newsgroups: sci.crypt
Subject: Force-Feeding New Technology to Spies
Date: Tue, 15 Dec 92 18:28:43 PST
Organization: The Portal System (TM)
Distribution: usa

What was the significance of Coventry in cryptographic 
history?   It shows that an adversary can safeguard their 
secrets with the home team, long after the adversary has been 
totally compromised.  The German Luftwaffe was free to bomb 
Coventry and kill British citizens despite the British 
Intelligence Service's possession of a complete decrypt of their 
plans.  I wonder how many Coventrys are occurring today, even 
with knowledge of silicon warfare, value-based cryptography, 
and value-based normative empathetic warfare.  The greatest 
danger in giving new ideas to a secret organization, is that the 
new ideas will sit idle in some bureaucrat's file cabinet, 
gathering dust, while good people die in battlefields and dark 
alleys  across the globe.  The way to prevent this from 
happening is to make sure that the ideas are transmitted on a 
"risky" medium, so that the transmission is considered "hot", 
and the transmitter is never fully and completely investigated.  
If the British had had a fire under their collective behinds, and 
felt that despite allowing Coventry to be bombed, someone might 
tell the Germans all about the whereabouts of the missing 
enigma, then perhaps the British would have saved their fellow 
countrymen, on the grounds that the beans might be spilled 
anyway.   This is the tactic to use when presenting new 
technology to a secret organization.
Newsgroups: sci.crypt
From: mccoy@ils.nwu.edu (Jim Mccoy)
Subject: Wordperfect decryption programs?
Organization: The Internet
Date: Thu, 17 Dec 1992 19:00:31 GMT

Does anyone out there have a program to remove the encryption from a
Wordperfect 5.1 file?  I have the Bergen and Caelli paper, but was hoping
that someone had implemented it in a program.  Any information regarding
such a program would be greatly appreciated (by myself and my friend's
prof; gotta love those stupid finals week pranks....)

Thanks,

jim mccoy
mccoy@ils.nwu.edu


-- 
Jim McCoy          |  PGP 2.0 Key md5 hash:
j-mccoy@nwu.edu    |  61323c49024cb089337c78a05aafe8c6
mccoy@ils.nwu.edu  |  finger mccoy@ils.nwu.edu for public key

Xref: sparky sci.crypt:5745 alt.security.pgp:209
From: weaver@kuttner.sfc.sony.com (Eric Weaver)
Newsgroups: sci.crypt,alt.security.pgp
Subject: RIPEM vs. PGP
Date: 16 Dec 92 19:54:38 GMT
Organization: SONY Advanced Video Technology Center San Jose, CA USA


I wish to issue a challenge to hackers on both sides of the red white & blue
curtain:

WHEREAS, we'uns can apparently only use RIPEM or such properly licensed RSA
software *legally*, AND

... the technical specs of a RIPEM compatible system are well-enough
known "out there" (outside the US) or in any event exportable, which the 
actual software is not), AND

... PGP has the ingredients for the RSA portion, and doubtless somewhere
there is a DES implementation already outside US Export Restrictions,

How about someone "out there" making a RIPEM-compatible system  rather in
the spirit of PGP, so we can get about exchanging our private mail, rather
than grousing about the legality of PGP?  I shall be happy to send U.S. $20
in support of this effort, and I encourage Messrs. Sternlight, Ellison, Boucher,
and all others in this brouhaha to do the same once a volunteer comes forth.

It's one thing to burn down the outhouse, and another to install plumbing...

-- 
Eric Weaver  Sony AVTC  677 River Oaks Pkwy, MS 35  SJ CA 95134  408 944-4904
& Chief Engineer, KFJC 89.7 Foothill College, Los Altos Hills CA 94022
-- 
Eric Weaver  Sony AVTC  677 River Oaks Pkwy, MS 35  SJ CA 95134  408 944-4904
& Chief Engineer, KFJC 89.7 Foothill College, Los Altos Hills CA 94022
Newsgroups: sci.crypt,alt.security.pgp
From: smb@research.att.com (Steven Bellovin)
Subject: Re: PGP as a World Standard
Date: Fri, 18 Dec 1992 02:13:08 GMT
Organization: AT&T Bell Laboratories

In article <1992Dec17.235959.1@nowhere.mil>, nobody@nowhere.mil writes:
> David Sternlight (strnlght@netcom.com> says:
> >Read my lips. PGP1.0 was contraband in the U.S., so much so that the
> >author pulled out. It was illegally exported.  PGP2.0 was based on it.
> >Thus the Europeans who use it don't have clean hands, regardless of
> >the state of the law there.
> 
> Which is interesting, considering an entry on a PGP public key ring I
> received recently:
> 
> Type bits/keyID   Date       User ID
> pub  1024/B33E65 1992/09/24  David Sternlight <strnlght@netcom.com>
> 
> 
> I guess it's "do as I say, not as I do", eh, Dave?

Ah, I love anonymous postings.  Umm -- who signed that key?  There's
this about certificates (i.e., about the much-maligned PEM) -- there's
a trail of evidence and authentication.

Quick -- how many people know how to generate a key with an arbitrary
name?  I thought so...

Btw -- the key might be genuine.  But an anonymous posting sure doesn't
give me any reason to think so.
Newsgroups: sci.crypt
From: rdippold@cancun.qualcomm.com (Ron Dippold)
Subject: Re: Wordperfect decryption programs?
Organization: Qualcomm, Inc., San Diego, CA
Date: Thu, 17 Dec 1992 22:00:12 GMT

mccoy@ils.nwu.edu (Jim Mccoy) writes:
>Does anyone out there have a program to remove the encryption from a
>Wordperfect 5.1 file?  I have the Bergen and Caelli paper, but was hoping
>that someone had implemented it in a program.  Any information regarding
>such a program would be greatly appreciated (by myself and my friend's
>prof; gotta love those stupid finals week pranks....)

I'll mail it to you...  implemented and improved!
-- 
English came into existence when a world phlegm shortage made the pronunciation
of most German consonants virtually impossible.
Newsgroups: sci.logic,comp.ai.philosophy
From: daryl@oracorp.com (Daryl McCullough)
Subject: Re: Self-Reference and Paradox (was Re: Human intelligence...)
Organization: ORA Corporation
Date: Sat, 12 Dec 1992 20:15:30 GMT

markh@csd4.csd.uwm.edu (Mark) writes:

>>All that it takes in order for a Godel-style proof to apply is the
>>following:
>>
>>1. We need a language L, with equality.
>>2. We need a notion of "theoremhood" for L. It is not important that
>>these theorems be the conclusions of proofs in first-order logic.
>>3. We need to be able to code formulas of L as terms in L.
>>4. We need to be able to express theoremhood in L.
>>5. We need to be able to express diagonalization in L.
>
>...
>...
>
>
>All you need is the following:
>1. Modus ponens
>2. The deduction theorem
>3. And a quotation function

That is not sufficient, as can easily be seen: Consider a language
with only one predicate symbol, equality. For terms, we allow any
string enclosed in quotations. For axioms, we have for each
string s, the axiom: s = s. For any two unequal strings s and t,
we have the axiom: not(s = t).

Thus we have theorems such as:

     "x = x" = "x = x"
     not("x = y" = "x = x")
     etc.

It should be clear that this is a complete theory, and therefore there
is no G such that G is true if and only if G is not a theorem.

By adding to the above language a new predicate symbol th, where th(x)
means that x is the quotation of a theorem, you can see that it is
possible to add enough axioms about th so that you again have a
complete theory.

In order to get incompleteness, you need quotation, expressibility of
theoremhood, and something like diagonalization, corresponding to
requirements 3,4, and 5 above.

Daryl McCullough
ORA Corp.
Ithaca, NY

Newsgroups: sci.logic
From: holmes@opal.idbsu.edu (Randall Holmes)
Subject: Re: Liar paradox
Organization: Boise State University
Date: Thu, 17 Dec 1992 15:46:37 GMT

In article <BzEM6u.2C1@watdragon.uwaterloo.ca> pasward@maytag.uwaterloo.ca (Paul A.S. Ward) writes:
>In article <GUTTMAN.92Dec16164336@circe.mitre.org> guttman@circe.mitre.org (Joshua D. Guttman) writes:
>
>>Kripke, who's always entertaining, says that the statement is quoted by St.
>>Paul in one of the Epistles, who writes that Epimenides, even one of their own,
>>states that all Cretans are liars.  St Paul adds, "This testimony is true."
>>Paul seems to have missed the logical subtlety here.
>
>Not necessarily.  Since Paul is not Cretan, he can agree with the statement
>"All Cretans are liars" without causing a paradox.  The essence is the 
>difference between the paradoxical "I always lie" and the non-paradoxical
>"You always lie" statements.
>
>Just sign me "One Paul defending another"
>
>Paul.

Epimenedes the Cretan himself can assert that all Cretans are liars
without danger of paradox, under most circumstances.  The precise
conditions under which this is possible depend on the definition of
"liar".  If a liar is a person who _always_ lies, then Epimenedes can
assert "All Cretans are liars" and be (in this instance) lying, as
long as some Cretan somewhere at some time made a true statement.
Paradox only ensues if every other proposition ever made by a Cretan
was just plain false.  If "liar" means a person who sometimes or even
usually lies but may occasionally tell the truth, then there is no
danger of paradox at all; Epimenedes may either be lying (there are
Cretans who always or habitually tell the truth) or he may be telling
the truth, in a momentary lapse into veracity.

But it is disturbing that the meaningful character of the assertion
depends on the extraneous fact of some other Cretan telling the truth
some time or other, in the first, interesting case.
-- 
The opinions expressed		|     --Sincerely,
above are not the "official"	|     M. Randall Holmes
opinions of any person		|     Math. Dept., Boise State Univ.
or institution.			|     holmes@opal.idbsu.edu
Newsgroups: sci.logic
From: pwestlak@eoe.co.uk (Peter Westlake)
Newsgroups: sci.logic
Subject: Liar paradox
Date: 16 Dec 92 18:16:54 GMT
Organization: EO Europe Limited, Cambridge, UK
X-Newsreader: TIN [version 1.1 PL6]


Please forgive me if this is a naive question (or even completely stupid :-)

The way I have heard the original Cretan liar paradox expressed is that
Epiminedes, a Cretan, said "All Cretans are liars". The reasoning goes that
as Epiminedes is known to be from Crete, he therefore claims to be a liar, 
and therefore claims not to be, which is a paradox.  But it seems to me
(in my ignorance) that this statement permits a consistent interpretation,
namely that SOME Cretans are liars, and that Epiminedes is one of them.
By supposing the existence of other Cretans, we avoid a paradox.

So a) I have the original statement wrong
or b) it never was a paradox really
or c) I have missed something obvious and everything I say is false.
Break it to me gently, especially if I have misspelled "Epi.*".

Peter.
-- 
Peter M Westlake                        EO Computer Ltd.,
Tel: +223-843131                        Abberley House,  Granhams Road,
Fax: +223-843032                        Great Shelford,
email:  pwestlak@eoe.co.uk              Cambridge CB2 5LQ,   England
Newsgroups: sci.logic
Subject: Absoluteness.
From: wft@math.canterbury.ac.nz (Bill Taylor)
Date: Fri, 18 Dec 1992 03:44:07 GMT
Organization: Department of Mathematics, University of Canterbury

Several times I thought I have understood the technical logical term "absolute".
But each time I leave the book thinking I know what it is, then the next day
find I can't remember it any more.   Perhaps the net folk will have more
success than the text books, driving it into my thick skull.  

So...

1) What does it mean for a set theoretic concept to be "absolute".

2) Could you briefly outline why, in particular, "being an ordinal" is
   absolute, but "being a cardinal" is not (or at least "having the same
   cardinality" is not.

3) Does (2) have anything at all to do with the recently-noted-here fact that
   in ZF- it is not possible to define a cardinal, though it is to define an
   ordinal. 

Thanks.     Bill Taylor.         wft@math.canterbury.ac.nz
Newsgroups: sci.logic
Subject: Re: Liar paradox
From: goldfarb@husc4.harvard.edu (Warren Goldfarb)
Date: 18 Dec 92 01:27:49 EST
Organization: Harvard University 

In article <1992Dec16.191006.16896@jarvis.csri.toronto.edu> leemike@eecg.toronto.edu (Michael Lee) writes:
>There is a collection of essays by Quine called `Paradoxes and Other
>Essays' which deals with the above paradox (nonparadox), with a quote
>by St. Paul followed by a blurb by Quine.  The first essay deals with
>antimonies in clear expository manner.

The collection by Quine is titled "The Ways of Paradox"; the essay in
question is eponymous.  The title is a reference to Gilbert and Sullivan's
"Pirates of Penzance":  "How quaint the ways of paradox/ At common sense
they gaily mock".

Warren Goldfarb
Department of Philosophy
Harvard University


Newsgroups: sci.logic
From: pasward@maytag.uwaterloo.ca (Paul A.S. Ward)
Subject: Re: Liar paradox
Organization: University of Waterloo
Date: Thu, 17 Dec 1992 12:47:17 GMT

In article <GUTTMAN.92Dec16164336@circe.mitre.org> guttman@circe.mitre.org (Joshua D. Guttman) writes:

>Kripke, who's always entertaining, says that the statement is quoted by St.
>Paul in one of the Epistles, who writes that Epimenides, even one of their own,
>states that all Cretans are liars.  St Paul adds, "This testimony is true."
>Paul seems to have missed the logical subtlety here.

Not necessarily.  Since Paul is not Cretan, he can agree with the statement
"All Cretans are liars" without causing a paradox.  The essence is the 
difference between the paradoxical "I always lie" and the non-paradoxical
"You always lie" statements.

Just sign me "One Paul defending another"

Paul.
From: mrh7507@tamsun.tamu.edu (Michael Hand)
Newsgroups: sci.logic
Subject: Re: Liar paradox
Date: 18 Dec 1992 12:40:15 -0600
Organization: Texas A&M University, College Station, TX
NNTP-Posting-Host: tamsun.tamu.edu

Titus 1:12.  
	One of themselves, a prophet of their own, said, "Cretans are 
	always liars, evil beasts, lazy gluttons."

So far, Paul hasn't himself uttered anything paradoxical, he's
only reported a potentially paradoxical utterance.  The Cretan's 
own claim is ambiguous (at least in this translation).  The 
"always" could be the one used by Russell in "On Denoting", not 
a quantifier over times, as is usual, but over individuals.  As 
Russell says

	C(everything) means "C(x) is always true"

Paul may merely mean to ensure that "Cretans" is read as a universal.
On the other hand, he may indeed mean "always" to quantify over times,
leaving it understood that he means *all* Cretans (as opposed to
*typical* Cretans, as when we say that dogs have four legs).
This reading is paradoxical, given the added assumption that if
someone is *always* a liar then s/he *never* tells the truth.  On
the third hand, if one lie makes the speaker a liar forever, then
there again is no paradox.
B-o} Michael
-- 
_______________________________________________________________________
-----------------------------------------------------------------------
Michael Hand                     phone (409)845-5660, fax (409)845-0458
Dept of Philosophy, Texas A&M Univ, College Station TX 77843-4237 U.S.A.
Newsgroups: sci.logic
From: holmes@opal.idbsu.edu (Randall Holmes)
Subject: Re: Absoluteness, and numbers and sets as well.
Organization: Boise State University
Date: Fri, 18 Dec 1992 17:04:08 GMT

It should be noted that it _is_ possible to define "cardinal number of
a well-founded set" in ZF- (the usual definition without choice,
relativized to the well-founded sets).  This demolishes completely
Zeleny's assertion that the notion of set in the usual set theory
depends on the prior notion of the ordinals.  ZF- certainly does not
depend on the ordinals for the definition of its concept of set, but
successfully defines the class of well-founded sets, which is the
universe of ZF, and the class of ordinals itself.  It cannot define a
general concept of cardinal number, though it _can_ define the notion
of two sets having the same cardinality, but it can define the notion
of cardinal needed in ZF; one then restricts one's attention to the
well-founded sets and one is doing ZF.  One could restrict oneself
further to ZFC by making the further restriction to the constructible
sets.  This makes it clear that the notion of cardinal number (but not
the notion of having the same cardinal) in ZF depends on the notion of
"well-founded set", not on the narrower notion of "ordinal".

The definition of absoluteness goes as follows:  let M be a transitive
class (a class which contains all elements of its elements).  A
formula P is absolute for M if the formula is equivalent to its
version with all quantifiers restricted to M, for any choice of
parameters from M.

Any formula in which each quantifier is restricted to a set is clearly
absolute if it makes sense in M at all (because all elements of a set
in M are in fact in M; if the set to which the quantifier is
restricted does not exist in M, the formula doesn't make sense in M).

It is possible to define "ordinal" using a restricted formula: "x is
transitive and x is linearly ordered by membership" iff x is an
ordinal, and every quantifier in the definition can be restricted to x
itself.  It is not possible to define cardinality using a restricted
formula: |A| = |B| if there is a bijection f from A to B; the problem
is that the transitive class M might not contain any witness f to this
fact, so, relative to M, A and B might have different cardinalities
due to the fact that no witness f to their equinumerousness is in M
(it would not be the case that there was a bijection f _in M_ from A
to B).

The non-definability of the cardinal numbers in ZF- is a different
kind of problem.  Equinumerousness (having the same cardinal) is
perfectly definable in ZF-; the problem is that it is impossible to
pick a canonical set to represent each cardinality in ZF-.
-- 
The opinions expressed		|     --Sincerely,
above are not the "official"	|     M. Randall Holmes
opinions of any person		|     Math. Dept., Boise State Univ.
or institution.			|     holmes@opal.idbsu.edu
Newsgroups: sci.logic
From: sasghm@theseus.unx.sas.com (Gary Merrill)
Subject: Re: Liar paradox
Originator: sasghm@theseus.unx.sas.com
Date: Thu, 17 Dec 1992 13:53:31 GMT
Organization: SAS Institute Inc.


In article <GUTTMAN.92Dec16164336@circe.mitre.org>, guttman@circe.mitre.org (Joshua D. Guttman) writes:
|> In article <1476@eouk13.eoe.co.uk> pwestlak@eoe.co.uk (Peter Westlake) writes:
|> 
|>    Please forgive me if this is a naive question (or even completely stupid :-)
|> 
|>    The way I have heard the original Cretan liar paradox expressed is that
|>    Epiminedes, a Cretan, said "All Cretans are liars". The reasoning goes that
|>    as Epiminedes is known to be from Crete, he therefore claims to be a liar, 
|>    and therefore claims not to be, which is a paradox.  But it seems to me
|>    (in my ignorance) that this statement permits a consistent interpretation,
|>    namely that SOME Cretans are liars, and that Epiminedes is one of them.
|>    By supposing the existence of other Cretans, we avoid a paradox.
|> 
|>    So a) I have the original statement wrong
|>    or b) it never was a paradox really
|>    or c) I have missed something obvious and everything I say is false.
|>    Break it to me gently, especially if I have misspelled "Epi.*".
|> 
|> 
|> I think you misspelled Epimenides, but you're right about it's not being
|> paradoxical, as stated.  I think that his statement was enough to make people
|> realize, though, that something very similar was going to be really paradoxical
|> ("This very sentence is false").
|> 
|> Kripke, who's always entertaining, says that the statement is quoted by St.
|> Paul in one of the Epistles, who writes that Epimenides, even one of their own,
|> states that all Cretans are liars.  St Paul adds, "This testimony is true."
|> Paul seems to have missed the logical subtlety here.
|> 
|> 	Joshua Guttman 

Or we have missed the subtlety of St. Paul ... possibly his sense of
humor?
-- 
Gary H. Merrill  [Principal Systems Developer, C Compiler Development]
SAS Institute Inc. / SAS Campus Dr. / Cary, NC  27513 / (919) 677-8000
sasghm@theseus.unx.sas.com ... !mcnc!sas!sasghm
Newsgroups: sci.logic
From: guttman@circe.mitre.org (Joshua D. Guttman)
Subject: Re: Liar paradox
Organization: The MITRE Corporation, Bedford, MA 01730
Date: Wed, 16 Dec 1992 21:43:36 GMT

In article <1476@eouk13.eoe.co.uk> pwestlak@eoe.co.uk (Peter Westlake) writes:

   Please forgive me if this is a naive question (or even completely stupid :-)

   The way I have heard the original Cretan liar paradox expressed is that
   Epiminedes, a Cretan, said "All Cretans are liars". The reasoning goes that
   as Epiminedes is known to be from Crete, he therefore claims to be a liar, 
   and therefore claims not to be, which is a paradox.  But it seems to me
   (in my ignorance) that this statement permits a consistent interpretation,
   namely that SOME Cretans are liars, and that Epiminedes is one of them.
   By supposing the existence of other Cretans, we avoid a paradox.

   So a) I have the original statement wrong
   or b) it never was a paradox really
   or c) I have missed something obvious and everything I say is false.
   Break it to me gently, especially if I have misspelled "Epi.*".


I think you misspelled Epimenides, but you're right about it's not being
paradoxical, as stated.  I think that his statement was enough to make people
realize, though, that something very similar was going to be really paradoxical
("This very sentence is false").

Kripke, who's always entertaining, says that the statement is quoted by St.
Paul in one of the Epistles, who writes that Epimenides, even one of their own,
states that all Cretans are liars.  St Paul adds, "This testimony is true."
Paul seems to have missed the logical subtlety here.

	Joshua Guttman
From: alti@dcs.ed.ac.uk (Thorsten Altenkirch)
Newsgroups: sci.logic
Subject: Re: decidable group theory
Date: 14 Dec 92 14:52:06 GMT
Organization: LFCS, Edinburgh

In article <1g282rINN5ja@eagle.dfki.uni-sb.de> treinen@dfki.uni-sb.de (Ralf Treinen) writes:

   In article <19921208.075322039663.NETNEWS@ALIJKU11>, groda@risc.uni-linz.ac.at (Giovanna Roda) writes:
   |> Suppose we are given an axiomatization for the theory of groups consisting
   |> of the following three axioms:
   |> (x*y)*z=x*(y*z)
   |> Vy x=y*z
   |> Vz x=y*z
   |> (where V is the existential quantifier).
   |> Is this theory decidable?

   No. This has been proven in

   @InCollection{Tar:groups53,
   author	= "Alfred Tarski",
   title	= "Undecidability in the Elementary Theory of Groups",
   pages	= "75--87",
   crossref= "TMR:Undecidable53"
   }

No I am slightly confused. Am I wrong remembering that the followoing
presentation of groups

	(x*y)*z=x*(y*z)
	x*e = x
	e*x = x
	i(x)*x = e
	x*i(x) = e

could be completed using the Knuth-Bendix algorithm & therefore is
decidable. How does this relate to the above mentioned result?

--

 Thorsten Altenkirch         	And there's a hand, my trusty fiere,
 Laboratory for Foundations  	   And gie's a hand o' thine,
 of Computer Science 	      	And we'll tak a right guid-willie waught
 University of Edinburgh     	   For auld lang syne!