Subject: Re: Re:Einstein's Constant
From: schmelze@fermi.wias-berlin.de (Ilja Schmelzer)
Date: 09 Jan 1997 20:16:27 GMT
In article <5b25ii$po3@asgard.actrix.gen.nz> cliff_p@actrix.gen.nz (Cliff Pratt) writes:
>>c is an absolute constant in the current units. Why? Every unit is
>>defined by a standard measurement. This definition changes from time
>>to time, if more accurate measurement devices occur.
>>
>C is an absolute constant. We cannot measure it exactly, but it is absolute.
>Similarly to the value of pi, which we know has a particular value, which
>we can measure or calulate aproximately, but NEVER exactly. This does not
>mean that pi varies.
We don't need to measure Pi, and we don't need to measure now c in m/s
(because of the definitions of 1m and 1s which are accepted now.)
>>>Absolutes are ideals that do not really exist.
>>
>>1 + 1 = 2 absolutely, really.
>>
>Really? I can think of a number system in which 1 + 1 = 0.
>It depends what you mean by "1", "+", "=" and "2".
Yes. The point of my remark was that it doesn't depend on experiment,
and if we have defined "1", "+", "=" and "2", it is absolutely true
(or absolutely wrong). Because definitions really exists, my example
shows that the original statement is wrong.
Subject: Re: Mars Rock Crock!
From: casanova@crosslink.net (Bob Casanova)
Date: Thu, 09 Jan 1997 23:04:56 GMT
On Wed, 08 Jan 1997 20:57:06 GMT, in sci.skeptic, =green@pipeline.com=
(Word Warrior) wrote:
>
>The immune system is quite capable of fending off damage
>from external sources of damage when it is properly
>fueled and managed.
Your substantiation for this would be...?
>_____________________________________________________________________________
>|Respectfully, Sheila ~~~Word Warrior~~~ green@pipeline.com|
>|Obligatory tribute to the founding fathers of the United States of America:|
>| This is not to be read by anyone under 18 years of age, who should read up|
>| on history and the First Amendment to the Constitution, as an alternative.|
>| *Animals, including humans, fart, piss, shit, masturbate, fuck and abort.*|
>^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>
(Note followups, if any)
Bob C.
"No one's life, liberty or property is safe while
the legislature is in session." - Mark Twain
Subject: Would a kinetic energy weapon leave residual radiation?
From: scott@eviews.com (Scott Ellsworth)
Date: Thu, 09 Jan 97 23:54:27 GMT
I had always been told that the majority of the the dangerous radiation and
fallout from an atomic bomb came from two sources, or roughly equal
importance. The Hiroshima bomb converted roughly a gram of matter into
energy, which was primarily in the form of ionizing radiation. It also spread
many, many uranium atoms far and wide.
Now, let's say that one wanted to make a very big bang in an ecologically
clean way, by accelerating a dime (roughly a gram or so) to about 0.86c, so
gamma is about 0.5, and thus the kinetic energy is reasonably close to the
mass energy. (Modulo the odd factor of two because I am feeling somewhat
lazy.)
Would the target of this see significant radiation, assuming that the tranfer
of energy from kinetic to thermal was essentially instantaneous? (Say, by
detonating the dime into pieces small enough and spread out enough that
they would be too small to go very far through the atmosphere and ground.)
My instincts say one would see significantly less, as there is no atomic
process going on, and no radiactive elements to begin with, but that some of
the tremendous kinetic energy would likely cause all sorts of strange things
to happen, such as crushing all sorts of nearby atomic nuclei into radioactive
ones.
I suppose an important point is just how the kinetic energy gets converted
into heat. Assume instead of a dime that one fired a very large laser pulse
along the projectile path to remove details like an atmosphere, then used a
fairly large plug of gas at such speeds. This might be diffuse enough that
the ground would stop it fairly quickly, no?
I became interested after reading one too many s.f. books involving kinetic
energy weapons at relativistic speeds.
Scott
Scott Ellsworth scott@eviews.com
"When a great many people are unable to find work, unemployment
results" - Calvin Coolidge, (Stanley Walker, City Editor, p. 131 (1934))
"The barbarian is thwarted at the moat." - Scott Adams
Subject: Re: Another defender of science arises
From: meron@cars3.uchicago.edu
Date: Thu, 9 Jan 1997 21:10:50 GMT
In article <19970109120700.HAA06136@ladder01.news.aol.com>, lbsys@aol.com writes:
>Im Artikel , meron@cars3.uchicago.edu
>schreibt:
>
>[real nice examples about a stupid public in the country populated with
>the worlds most intelligent people woefully snipped.... ;-]
Well, be careful not to overestimate them :-)
>
>>OK, so now it is back to the saying about democracy and its
>>"justness". What this saying says in effect is the following: In
>>democracy people ore the sovereign. They have the ultimate right and
>>the ultimate power, the power to chose who'll govern. But, with rights
>>come responsibilities and obligations. Being a sovereign doesn't just
>>mean the power to decide, it means also the obligation to live with
>>the consequences of your decisions. And if you screwed up, you pay.
>>Sovereignty is responsibility.
>
>Hmm, hmm. Someone wisely once pointed out, that a right granted is just a
>right in the hands of those who are enabled to use it. E.g. the right to
>built a house is a right only, if you have money (space) enough to do so.
>If not, this right has no meaning for you, wether it's granted or
>forbidden.
>
Agreed. And if you're trying to convince me that lots of people (the
vast majority possibly) lack the mental equipment or knowledge which a
citizen of a democracy should've in order to carry his
responsibilities, then you're preaching to the converted. But, what
are we to do? Reserve the right to vote to a selected group only?
And who will decide who belongs in this selected group? How would we
prevent such system from turning into an oligarchy?
... snip ...
>
>IMHO it is unethical to grant sovereignty to someone, who is not enabled
>to make real use of it, and then leave him alone with it (remember Jossele
>and the number game?). Of course we could make laws, which tie up
>politicians in a way, they can't get away with betrayal etc. or at least
>strengthen this way a bit. Like that: In Germany, if your in Parliament,
>you may as well be a member of the board of a huge enterprise or a bank,
>or you may have a consultant contract etc. Who is so naive to think, that
>this is NOT misused in the way, that this politician will try to use his
>influence to do 'his' company something good? Why not say: The day you get
>elected we pay you a very decent wage (it's 10.000$ over here), but you
>will have to refrain from any other economical activity? And to ensure
>this, you have to publish your tax forms. Yes, of course, that's hard to
>swallow, but the one who wants to govern me, has to pay a price for this
>power.
Definitely.
>
>>>In the 'Bill of Human Rights', one right has been forgotten:
>>>it's the right to be governed by decent, honest people.
>
>>No, there is no such right. You can state it but a right
>>without a mechanism to achieve and maintain it is meaningless.
>
>I think you should read the human rights first..... ;-). *All of the
>claimed 'human rights' are purely 'stated' and none are granted by nature
>nor is there any mechanism given to achieve or maintain them. This is left
>to the legislature of the respective country.
I didn't say "granted by nature." What I said (possibly in an ackward
fashion) is that there are rights which cannot be granted by people
either, because a mechanism guaranteeing these rights cannot be
devised. Regarding the one you advocate, "the right to be governed by
decent, honest people", what more can you do then grant "the right to
hire and the right to fire".
>
>>It is like stating "everybody has the right to be happy". So, what
>>he's supposed to do if he isn't? Sue the people? The government?
>>Mother Nature? At most you can say "people have the right to pursue
>>happiness." Still vague, but within some limits can be assured.
>
>Sorry, but that doesn't fit. We may not be able to precisely define what
>'decent and honest' is, but we can draw a line at least, where it is
>illegal (and there should have been no way to pardon Tricky Dicky for his
>crockery
Agreed.
>and McNamara should be jailed for having caused the death of ten
>thousands of soldiers by ignorance - any trucker who is caught speeding
>would be very, very responsible if he caused a fatal accident b/c of his
>ignoring the speed limit, so why is Mr McNamara NOT responsible for making
>decisions bare any knowledge about the facts?).
Here I disagree. You use "ignorance" in two different ways. When I'm
speeding, I'm aware of the existance of a speed limit, I just
consciously choosing to ignore it. On the other hand, when I act
without adequate knowledge, but not being aware of it, I may be guilty
of stupidity, but not a crime.
But, on a more serious note, you can be jailed for breaking a law
(which Nixon did) but not for an action which isn't contrary to any
law, even if the consequences are bad. You may say that this is a bad
system since people may cause enormous damage and go unpunished. But,
that's the only system that makes sense. There are laws, people know
what they're and know that they're not guilty of a crime if they don't
break the laws. If you institute a system where people can be tried
for "doing something bad" though there is no law defining the crime,
you've just created a horror, a system where those in power are free
to try and jail anybody whom they happen to dislike. I'll pass.
>
>But try to define 'happiness'. And how come, that even with this 'right'
>granted in the US, people defining their happiness in smoking pot, are not
>allowed to 'pursue' their happiness then? No, no, a stated right to be
>governed by decent, honest people of course would call for legislative
>action, and that's what's needed. Otherwise those who govern us, will
>remain to be uncontrollable just like in the past.
All the legislation that's needed is in place already. People can
choose public officials and can throw them out of office. If they
happened to break a law, the mechanisms to exact justice exist. So
the tools are there, in the hands of the people and, imperfect as this
arrangement is, I wouldn't want to put these tools in any other hands.
>
>>No guarantees of success, mind you.
>
>Never, that's for sure. But still we have to try :-)
>
Yep. We have to. The alternatives aren't pleasant.
Mati Meron | "When you argue with a fool,
meron@cars.uchicago.edu | chances are he is doing just the same"
Subject: Re: Frequency-Space paradox?
From: "Peter Diehr"
Date: 10 Jan 1997 00:35:14 GMT
ca314159 wrote in article
<32D58D08.5955@bestweb.net>...
> meron@cars3.uchicago.edu wrote:
> > So the question is how much of the asymetry is just an
"operational
> > asymetry" in the sense that in specific regions of the
parameter space
> > one or the other may be easier to measure. Moreover, the
"easier" is
> > a purely temporary label. Hundred years ago we had primary
standards
> > for length and time and the speed of light was expressed in
terms of
> > these two, since it was easier to measure length and time.
Nowadays
> > the it became easier to measure the speed of light to high
accuracy so
> > it becamme a primary standard, while the meter became a
secondary one.
>
> It's interesting how the spaces get mapped onto each other.
> Peter Diehr pointed out some of the pairs. Its easy to see
> how frequency-time get mapped onto energy-time from E=hf
> as well as the others. Then the frequency-time pair is more
> fundemental ? What then are the fundemental pairs ?
> Are E and B also conjugate in the same sense ?
>
I don't think of any of the pairs as being more fundamental than any
of the
others. However, it would be reasonable to use the three that I
listed
earlier as the most useful pairings, since they are tied to the
three great
conservation laws.
But any type of coordinate will wind up with a conjugate momenta.
It is a definitional statement.
As to E and B (the electric and magnetic fields); no, they have a
different relationship. They are components of the electromagnetic
field tensor. We split the field tensor up this way because it
corresponds
to the isolated phenomena of static electric fields, and of magnetic
fields due to currents.
But you will find that as components of a tensor, it all depends
upon
"how you look at it". That is, it depends upon the coordinate
system.
For example, observers in different inertial reference frames will
split
the tensor down differently, even though it represents the same
object.
Best Regards, Peter
PS: the appropriate conjugate momenta for electromagnetic situations
is based upon the potentials, not the fields. Thus you end up with
the
magnetic vector potential, A. This is then projected against the
velocity,
since the Lorentz force law has a velocity dependence.
Thus you get .
Subject: Re: A wee dram o' Philosophy...
From: meron@cars3.uchicago.edu
Date: Thu, 9 Jan 1997 21:13:23 GMT
In article <19970109120700.HAA06137@ladder01.news.aol.com>, lbsys@aol.com writes:
>Im Artikel , meron@cars3.uchicago.edu
>schreibt:
>
>>
>>Seriously now, I hope you don't expect me to define Truth (with
>>capital T) the way our friends from a.p. wanted since this seems
>>beyond anybody's ability (though some philosophers claim otherwise).
>>But I would settle for a lower case, mundane truth, meaning just
>>"statements which to the best of my knowledge correspond to what
>>happened or was happening". Not a very precise definition here but I
>>see no clear binary (that's for you, Lorenz) test which can be applied
>>to anything and yields an answer "truth" or "not truth". There are
>>always statements which we recognize as being (to the best of our
>>knowledge, again) true, those we recognize as clearly false, and a
>>hell of a lot in between.
>
>Very much so. Although within the last 500 years, a hell of a lot of the
>in-betweens have been cleared up to a great extent. We know now that
>lightnings are electric phenomena and it is not the god Thor hurling his
>javelin at us... (which has diminished the influence of religion quite a
>bit ;-)
>
And a good thing it is. Lets just hope that we won't regress back
into the habits of the past. I don't know what's the situation in
Europe but in the States things seem to be heading this way, at times.
Mati Meron | "When you argue with a fool,
meron@cars.uchicago.edu | chances are he is doing just the same"
Subject: Re: paradox
From: jhallen@world.std.com (Joseph H Allen)
Date: Thu, 9 Jan 1997 21:24:02 GMT
In article <01bbfdcb$f741e5a0$LocalHost@brian>,
Brian Tozer. wrote:
>> >> Here are some paradoxes: Now the negation of "all ravens are black" is
>> >> "all non-black things aren't ravens". The two statements are
>> >> logically equivalent.
>Why is not the first word negated?
I should not have said negated. The two statements are equivalent, not
negations of each other. So the paradox should have read:
Suppose you say that all ravens are black. How do you know? You've seen,
say, 100 ravens and they were all black so you infer that all of them are
black. Each additional black raven you find adds support to your
generalization.
Now the statement "all non-black things aren't ravens" is logically
equivalent to "all ravens are black". Thus all of the non-black things you
find which aren't ravens (your red coat, the white ceiling, etc.) also
support your generalization that "all ravens are black".
--
/* jhallen@world.std.com (192.74.137.5) */ /* Joseph H. Allen */
int a[1817];main(z,p,q,r){for(p=80;q+p-80;p-=2*a[p])for(z=9;z--;)q=3&(r=time(0)
+r*57)/7,q=q?q-1?q-2?1-p%79?-1:0:p%79-77?1:0:p<1659?79:0:p>158?-79:0,q?!a[p+q*2
]?a[p+=a[p+=q]=q]=q:0:0;for(;q++-1817;)printf(q%79?"%c":"%c\n"," #"[!a[q-1]]);}
Subject: Re: Size of the universe?
From: baez@math.ucr.edu (john baez)
Date: 7 Jan 1997 15:26:12 -0800
In article <01bbfcdf$26685960$ee26efa8@jblood>,
Lord of the Flies wrote:
>Macarthur Drake wrote in article
><5ark4e$np1@agate.berkeley.edu>...
>> Are you saying that space itself has expanded. That is,
>> if we measured a meter a billion years ago, that same meter would now be
>> 10 meters or something?
>These are all very good questions Mr Drake. The answer to the first
>question is yes. This is what current theory is saying.
While Mr Drake's questions are certainly good for provoking
thought, this first one is quite vague, and as Warren Anderson
has pointed out in another post, the answer is "it depends".
What do you mean by "measuring a meter"? We must measure
some particular thing by some particular method to make the
question precise. Obviously if we measured a meter stick
using itself a billion years ago, it would be one meter
stick long, and now it would still be exactly one meter
stick long, since it's exactly as long as itself!
What current theory predicts is that if you measure the distance
between galaxies that are not in the same gravitationally bound cluster,
by (for example) seeing how long it takes a message to make a round
trip, relative to a good clock on one of the galaxies, and then do this
again later, the distance will have increased.
The same would not be true, however, if instead of two distant
galaxies we used two different points on the earth. (Well, the
earth might expland or shrink a bit for reasons of its own, but
not for any reason related to the Big Bang!)
All this stuff is in the FAQ, so I urge folks to read more about
it there. Try going to
http://math.ucr.edu/home/baez/physics/faq.html
>The second equation stems from misleading information. The universe is
>"infinite" in that if you walk in one direction you will never reach an
>"edge". But this is true of the earth (certainly not infinite in size) as
>you walk along the surface. In fact it is this closed sphere like surface
>that we imagine as our universe (its actually a four-dimensional
>sphere-like structure, try imagining that!). So in theory if you walk away
>from the earth in any direct, you will eventually return to the earth.
>This is the extent of the universe's infinite nature.
It's actually a completely open question, experimentally speaking,
as to whether the universe is infinite in extent or finite but
unbounded as Jason Blood claims here. The experimental evidence
doesn't point too strongly either way. Folks working to measure the Hubble
constant and trying to find the (supposed) missing mass are desperately
eager to learn more about this. Right now lots of the puzzle pieces
don't seem to fit together too well.
Subject: Re: Infinitude of Primes in P-adics
From: dik@cwi.nl (Dik T. Winter)
Date: Fri, 10 Jan 1997 01:13:09 GMT
In article <5b0mi4$3k7$1@dartvax.dartmouth.edu> Archimedes.Plutonium@dartmouth.edu (Archimedes Plutonium) writes:
> But you Dik assume that 3 is prime in the first place, do you not, in
> order to construct the 3-adics.
Yup, a prime in the (finite) natural numbers. 3 is not a prime in the
rationals or in the reals. There are no primes in the rationals or in
the reals because they form a field.
> So, if 2 or 3, 5, is not prime then Dik, how in the world can you
> even start to construct the 2-adics or 3-adics or 5-adics.
By starting with (finite) natural numbers.
> So Dik, please tell when in the discussion you want to claim 3 is a
> prime number in order to prove 3-adics is a field, and then, when do
> you want to renounce that 3 was prime so that you can say that the
> 3-adics is not a field?
You have got this backwards. I never proof that the 3-adics form a field,
I assert they do *not* form a field. And in the *not-field* (but a ring)
3 is the (only) prime.
Again: if there is a field there are no primes, if there is a prime there
is no field. The 3-adics do not form a field because 3 has no inverse.
Moreover, 3 generates a prime ideal in the 3-adics, and so they are also
not a field for this reason.
--
dik t. winter, cwi, kruislaan 413, 1098 sj amsterdam, nederland, +31205924131
home: bovenover 215, 1025 jn amsterdam, nederland; http://www.cwi.nl/~dik/
Subject: Re: Mars Rock Crock!
From: casanova@crosslink.net (Bob Casanova)
Date: Thu, 09 Jan 1997 23:03:06 GMT
On Wed, 08 Jan 1997 20:54:25 GMT, in sci.skeptic, =green@pipeline.com=
(Word Warrior) wrote:
>patrick@gryphon.psych.ox.ac.uk (Patrick Juola) wrote:
>
>>In article <5api57$pvv@dropit.pgh.net> green@pipeline.com writes:
>>>JohnAcadInt wrote:
>>>>It might be interesting, for example, to offer prizes
>>>>for a cancer cure. Say, a billion dollars to the first
>>>>team to crack it. [ I hope nobody is going to complain
>>>>that we couldn't measure the results! Ed.]
>>>People properly nourished in clean surroundings won't
>>>get cancer at all.
>
>>Clean surroundings, of course, being defined as excluding all radiation
>>such as sunlight.
>
>Your definition is inaccurate.
Not if your objective is to prevent cancer, since the UV in sunlight
can lead to skin cancer.
>
>>First, that's not a cure, that's a preventative. Second, it's not
>>a preventative as the treatment is more injurious than the disease.
>
>Your substantiation for that would be _?_
>_____________________________________________________________________________
>|Respectfully, Sheila ~~~Word Warrior~~~ green@pipeline.com|
>|Obligatory tribute to the founding fathers of the United States of America:|
>| This is not to be read by anyone under 18 years of age, who should read up|
>| on history and the First Amendment to the Constitution, as an alternative.|
>| *Animals, including humans, fart, piss, shit, masturbate, fuck and abort.*|
>^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>
(Note followups, if any)
Bob C.
"No one's life, liberty or property is safe while
the legislature is in session." - Mark Twain
Subject: Tampere Replication Found
From: Troy Dawson
Date: Thu, 09 Jan 1997 22:36:29 +0900
A researcher in Ohio has attempted to replicate Podkletnov's
gravity modification superconductor results.
The Setup
---------
1) 1" YBCO superconducting disc.
2) Magnetic field generator (producing a 600 gauss/60Hz EM field).
3) Pan-and-beam balance:
Beam: bamboo, coming to a point on one end (24.6cm long,
weight 1.8647g)
Pan: a cardboard rectangle (15.8cm x 10.0cm x 0.131mm) is suspended
from the balance with 28.1cm of cotton string.
A polystyrene "pan" (7.2cm x 8.7cm x 1.78 mm) is attached with paper
masking tape to the cardboard rectangle.
The pan assembly (w/ string, cardboard, tape) weighs 1.6502g.
The balance is suspended from the end of a 5' wood beam by ~30cm
of monofilament fishing line (8lb. test) attached to the balance's
center of mass (5.5cm from the pan end).
The other end of the crossbeam is firmly anchored by a heavy
steel tripod (normally used for holding photographic lights).
4) Thermal and EM isolation is hopefully provided by a glass plate
(15cm x 30cm, 0.7cm thick) with a brass screen attachment.
This plate-and-brass-screen assembly is held about ~4.5cm below the
pan by a '3-finger' ring stand clamp.
5) A straightsided, 6" diameter, 10" deep dewar with 3 - 4" of
liquid nitrogen is used to cool the sc below its Tc, and is
removed from the experiment area before the trial.
Experiment Procedure
--------------------
1) The YBCO superconductor is placed in a liquid nitrogen bath and
allowed to come to liq N temp (as indicated when the boiling of
the liq N ceases). The sc will remain below its 90C Tc for the
duration of the trial (less than 20sec).
3) The disc is then removed from the bath & placed on a strong NdFeB
magnet to induce a supercurrent. The Meissner effect is counteracted
by a wooden stick. The sc disc has a cotton string attached to it to
assist handling.
3) The HTSC and wooden stick assembly is placed on the EM field
generator, about 33cm below the glass/screen isolation plate.
The HTSC is ~40cm *directly* below the pan.
4) The AC field generator is then cycled for ~ 5sec with 0.75sec
equal-time on/off pulses.
Experiment Findings
-------------------
o While AC current was flowing though the AC field generator, the
balance pointer was deflected 2.1mm downward.
o When the AC field generator was pulsed with no superconductor
present, there was no measurable pointer deflection.
Experimenter's Comments
-----------------------
o The additional pan weight required to *raise* the balance pointer
2.1mm was later found to be 0.0891g (~5% of the pan's weight).
o The idea was that the 'column' of modified gravity (as described by
Podkletnov) HAS to hit the pan somewhere ...as the HTC is only 1"
diameter and the pan is larger.
o Only one experimental setup was constructed, with several trials.
The experimenter welcomes further replication attempts & comments.
==
For now, you can direct comments to:
grav@t-d.com
If the traffic warrants, I'll start up an anti-grav e-mail listserver.
=td=
Subject: Re: Mars Rock Crock!
From: casanova@crosslink.net (Bob Casanova)
Date: Thu, 09 Jan 1997 22:59:26 GMT
On Wed, 08 Jan 1997 12:52:18 GMT, in sci.skeptic, ~green@pipeline.com~
(~Word Warrior~) wrote:
>patrick@gryphon.psych.ox.ac.uk (Patrick Juola) wrote:
>
>>In article <5aqk01$mre@news.ox.ac.uk> patrick@gryphon.psych.ox.ac.uk (Patrick Juola) writes:
>>>In article <5api57$pvv@dropit.pgh.net> green@pipeline.com writes:
>>>>JohnAcadInt wrote:
>>>>>It might be interesting, for example, to offer prizes
>>>>>for a cancer cure. Say, a billion dollars to the first
>>>>>team to crack it. [ I hope nobody is going to complain
>>>>>that we couldn't measure the results! Ed.]
>>>>People properly nourished in clean surroundings won't
>>>>get cancer at all.
>>>Clean surroundings, of course, being defined as excluding all radiation
>>>such as sunlight.
>[sunlight is a disinfectant]
It's also carcinogenic.
>>>First, that's not a cure, that's a preventative. Second, it's not
>>>a preventative as the treatment is more injurious than the disease.
>[unsubstantiated]
>>Oh, yes. I forgot. Third, it's not a preventative as it doesn't
>>prevent....
>
>Your substantiation for that would be _?_
>
>
>_____________________________________________________________________________
>|Respectfully, Sheila ~~~Word Warrior~~~ green@pipeline.com|
>|Obligatory tribute to the founding fathers of the United States of America:|
>| This is not to be read by anyone under 18 years of age, who should read up|
>| on history and the First Amendment to the Constitution, as an alternative.|
>| *Animals, including humans, fart, piss, shit, masturbate, fuck and abort.*|
>^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>
(Note followups, if any)
Bob C.
"No one's life, liberty or property is safe while
the legislature is in session." - Mark Twain
Subject: Re: paradox
From: Christopher R Volpe
Date: Thu, 09 Jan 1997 18:25:14 -0500
Herman Rubin wrote:
>
> In article <32D3ED92.31A6@cdf.toronto.edu>,
> Luben Tuikov wrote:
> >Joseph H Allen wrote:
>
> >> Now the negation of "all ravens are black" is "all non-black things aren't
> >> ravens". The two statements are logically equivalent. Thus all of the
> >> non-black things you find which aren't ravens (your red coat, the white
> >> ceiling, etc.) also support your generalization that "all ravens are black".
>
> >> Now this sounds silly, but it is actually logically correct. If you lived
>
[snip]
> >Don't meddle with the quality but with the quantifier:
> >the negation of "all ravens are black" is "not all ravens are black",
> >namely I've found at least one that is NOT black (maybe it's brown).
>
> It was not stated that this was a negation, but an equivalence.
Gee, it sure sounded to me like he was stating that this was a negation.
I must have been tricked into thinking that by the first sentence you
quoted, which begins, "Now the negation of 'all ravens are black'
is...".
The fact that he contradicted himself by subsequently saying it was an
equivalence is irrelevant. The first thing Mr. Allen said was that it
was a negation, and that's the statement that Mr. Tuikov took issue
with.
--
Chris Volpe Phone: (518) 387-7766
GE Corporate R&D; Fax: (518) 387-6560
PO Box 8 Email: volpecr@crd.ge.com
Schenectady, NY 12301 Web: http://www.crd.ge.com/~volpecr
