Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-08-09 Thread Rustom Mody
On Sunday, August 9, 2015 at 2:57:20 AM UTC+5:30, Marko Rauhamaa wrote:
 Marko Rauhamaa :
 
  Steven D'Aprano :
 
  The contemporary standard approach is from Zermelo-Fraenkel set
  theory: define 0 as the empty set, and the successor to n as the
  union of n and the set containing n:
 
  0 = {} (the empty set) 
  n + 1 = n ∪ {n}
 
  That definition barely captures the essence of what a number *is*. In
  fact, there have been different formulations of natural numbers.
 
 Rehashing this old discussion. I ran into this wonderful website:
 
   URL: http://at.metamath.org/mpeuni/mmset.html

Attention you Hilbertian!
Gödelian here — http://blog.languager.org/2015/07/cs-history-2.html 
:-)
Thanks for that link. Need to study it carefully
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-24 Thread Grant Edwards
On 2015-07-24, Paul Rubin no.email@nospam.invalid wrote:
 Grant Edwards invalid@invalid.invalid writes:

 You can always pick out the topologist at a conference: he's the one
 trying to dunk his coffee cup in his doughnut.

 Did you hear about the idiot topologist?  He couldn't tell his butt
 from a hole in the ground, but he *could* tell his butt from two
 holes in the ground.

Wow.  Now I know _two_ topologist jokes.  The girls are going to be
impressed!

-- 
Grant Edwards   grant.b.edwardsYow! I just got my PRINCE
  at   bumper sticker ... But now
  gmail.comI can't remember WHO he
   is ...
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-24 Thread Mark Lawrence

On 24/07/2015 15:13, Grant Edwards wrote:

On 2015-07-24, Paul Rubin no.email@nospam.invalid wrote:

Grant Edwards invalid@invalid.invalid writes:


You can always pick out the topologist at a conference: he's the one
trying to dunk his coffee cup in his doughnut.


Did you hear about the idiot topologist?  He couldn't tell his butt
from a hole in the ground, but he *could* tell his butt from two
holes in the ground.


Wow.  Now I know _two_ topologist jokes.  The girls are going to be
impressed!



Here comes the third.

Q: How many topologists does it take to change a light bulb?
A: It really doesn't matter, since they'd rather knot.

https://www.ocf.berkeley.edu/~mbarrien/jokes/lightblb.txt

--
My fellow Pythonistas, ask not what our language can do for you, ask
what you can do for our language.

Mark Lawrence

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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-24 Thread Paul Rubin
Grant Edwards invalid@invalid.invalid writes:
 Did you hear about the idiot topologist?  He couldn't tell his butt
 from a hole in the ground, but he *could* tell his butt from two
 holes in the ground.

 Wow.  Now I know _two_ topologist jokes.  The girls are going to be
 impressed!

I got it from here:

http://mathoverflow.net/questions/1083/do-good-math-jokes-exist
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Marko Rauhamaa
Chris Angelico ros...@gmail.com:

 Fortunately, we don't need to completely understand it. New Horizons
 reached Pluto right on time after a decade of flight that involved
 taking a left turn at Jupiter... we can predict exactly what angle to
 fire the rockets at in order to get where we want to go, even without
 knowing how that gravity yank works.

 Practicality beats purity?

Engineer!

At the time I was in college I heard topology was very fashionable among
mathematicians. That was because it was one of the last remaining
research topics that didn't yet have an application.


Marko
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Grant Edwards
On 2015-07-23, Marko Rauhamaa ma...@pacujo.net wrote:
 Chris Angelico ros...@gmail.com:

 Fortunately, we don't need to completely understand it. New Horizons
 reached Pluto right on time after a decade of flight that involved
 taking a left turn at Jupiter... we can predict exactly what angle to
 fire the rockets at in order to get where we want to go, even without
 knowing how that gravity yank works.

 Practicality beats purity?

 Engineer!

 At the time I was in college I heard topology was very fashionable among
 mathematicians. That was because it was one of the last remaining
 research topics that didn't yet have an application.

You can always pick out the topologist at a conference: he's the one
trying to dunk his coffee cup in his doughnut.

[Hey, how often do you get to use a topology  joke.]

--
Grant

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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Chris Angelico
On Fri, Jul 24, 2015 at 7:59 AM, Marko Rauhamaa ma...@pacujo.net wrote:
 Laura Creighton l...@openend.se:

 In a message of Fri, 24 Jul 2015 00:29:28 +0300, Marko Rauhamaa writes:
At the time I was in college I heard topology was very fashionable
among mathematicians. That was because it was one of the last
remaining research topics that didn't yet have an application.

 I have a very good freind who is a knot-theorist. (Chad Musick, who
 may have proven something wonderful.) see:
 http://chadmusick.wikidot.com/knots He says there are lots of
 applications for this in the field of circuit board layouts. And most
 mathematicians accept knot-theory as part of topology.

 So topology, too, is lost.

You remind me of the hipster mathematician cook, who burned himself by
calculating pie before it was cool.

ChrisA
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread MRAB

On 2015-07-23 22:50, Mark Lawrence wrote:

On 23/07/2015 22:29, Marko Rauhamaa wrote:

Chris Angelico ros...@gmail.com:


Fortunately, we don't need to completely understand it. New Horizons
reached Pluto right on time after a decade of flight that involved
taking a left turn at Jupiter... we can predict exactly what angle to
fire the rockets at in order to get where we want to go, even without
knowing how that gravity yank works.

Practicality beats purity?


Engineer!



Heard the one about the three engineers in the car that breaks down?

The chemical engineer suggests that they could have contaminated fuel.
They should try and get a sample and get someone to take it to a lab for
analysis.

The electrical engineer suggests that they check the battery and the
leads for any problems.

The Microsoft engineer suggests that they close all the windows, get out
of the car, get back in the car, open all the windows and see what happens.


And an Apple engineer would suggest buying a new car that runs only on
its manufacturer's brand of fuel. :-)

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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Laura Creighton
In a message of Thu, 23 Jul 2015 23:01:51 +0100, MRAB writes:

And an Apple engineer would suggest buying a new car that runs only on
its manufacturer's brand of fuel. :-)

Before you do that, read this:
http://teslaclubsweden.se/test-drive-of-a-petrol-car/
(ps, if you can read Swedish, the Swedish version is a little more fun.)

Laura
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Mark Lawrence

On 23/07/2015 22:29, Marko Rauhamaa wrote:

Chris Angelico ros...@gmail.com:


Fortunately, we don't need to completely understand it. New Horizons
reached Pluto right on time after a decade of flight that involved
taking a left turn at Jupiter... we can predict exactly what angle to
fire the rockets at in order to get where we want to go, even without
knowing how that gravity yank works.

Practicality beats purity?


Engineer!



Heard the one about the three engineers in the car that breaks down?

The chemical engineer suggests that they could have contaminated fuel. 
They should try and get a sample and get someone to take it to a lab for 
analysis.


The electrical engineer suggests that they check the battery and the 
leads for any problems.


The Microsoft engineer suggests that they close all the windows, get out 
of the car, get back in the car, open all the windows and see what happens.


--
My fellow Pythonistas, ask not what our language can do for you, ask
what you can do for our language.

Mark Lawrence

--
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Marko Rauhamaa
Ian Kelly ian.g.ke...@gmail.com:

 Gravity existed before Newton, but the *theory* of gravity did not, so
 he composed the theory?

Ironically, gravity is maybe the least well understood phenomenon in
modern physics.


Marko
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Mark Lawrence

On 23/07/2015 23:01, MRAB wrote:

On 2015-07-23 22:50, Mark Lawrence wrote:

On 23/07/2015 22:29, Marko Rauhamaa wrote:

Chris Angelico ros...@gmail.com:


Fortunately, we don't need to completely understand it. New Horizons
reached Pluto right on time after a decade of flight that involved
taking a left turn at Jupiter... we can predict exactly what angle to
fire the rockets at in order to get where we want to go, even without
knowing how that gravity yank works.

Practicality beats purity?


Engineer!



Heard the one about the three engineers in the car that breaks down?

The chemical engineer suggests that they could have contaminated fuel.
They should try and get a sample and get someone to take it to a lab for
analysis.

The electrical engineer suggests that they check the battery and the
leads for any problems.

The Microsoft engineer suggests that they close all the windows, get out
of the car, get back in the car, open all the windows and see what
happens.


And an Apple engineer would suggest buying a new car that runs only on
its manufacturer's brand of fuel. :-)



Like it, marks out of 10, 15 :)

--
My fellow Pythonistas, ask not what our language can do for you, ask
what you can do for our language.

Mark Lawrence

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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Laura Creighton
In a message of Fri, 24 Jul 2015 00:29:28 +0300, Marko Rauhamaa writes:
Chris Angelico ros...@gmail.com:

 Fortunately, we don't need to completely understand it. New Horizons
 reached Pluto right on time after a decade of flight that involved
 taking a left turn at Jupiter... we can predict exactly what angle to
 fire the rockets at in order to get where we want to go, even without
 knowing how that gravity yank works.

 Practicality beats purity?

Engineer!

At the time I was in college I heard topology was very fashionable among
mathematicians. That was because it was one of the last remaining
research topics that didn't yet have an application.


Marko

I have a very good freind who is a knot-theorist.  (Chad Musick, who
may have proven something wonderful.) see: http://chadmusick.wikidot.com/knots
He says there are lots of applications for this in the field of circuit
board layouts.  And most mathematicians accept knot-theory as part of
topology.

Laura
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Marko Rauhamaa
Laura Creighton l...@openend.se:

 In a message of Fri, 24 Jul 2015 00:29:28 +0300, Marko Rauhamaa writes:
At the time I was in college I heard topology was very fashionable
among mathematicians. That was because it was one of the last
remaining research topics that didn't yet have an application.

 I have a very good freind who is a knot-theorist. (Chad Musick, who
 may have proven something wonderful.) see:
 http://chadmusick.wikidot.com/knots He says there are lots of
 applications for this in the field of circuit board layouts. And most
 mathematicians accept knot-theory as part of topology.

So topology, too, is lost.


Marko
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Chris Angelico
On Fri, Jul 24, 2015 at 7:50 AM, Mark Lawrence breamore...@yahoo.co.uk wrote:
 Heard the one about the three engineers in the car that breaks down?

 The chemical engineer suggests that they could have contaminated fuel. They
 should try and get a sample and get someone to take it to a lab for
 analysis.

 The electrical engineer suggests that they check the battery and the leads
 for any problems.

 The Microsoft engineer suggests that they close all the windows, get out of
 the car, get back in the car, open all the windows and see what happens.


And the data scientist proved that the phenomenon is not wholly
unlikely, given the predicted average reliability of cars; further
studies would require improved sample size.

ChrisA
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Rustom Mody
On Thursday, July 23, 2015 at 12:28:19 PM UTC+5:30, Gregory Ewing wrote:
 Rustom Mody wrote:
  Ive known good ones) most practicing-mathematicians proceed on the 
  assumption 
  that they *discover* math and not that they *invent* it.
 
 For something purely abstract like mathematics, I don't
 see how there's any distinction between discovering and
 inventing. They're two words for the same thing.
 
 I don't know what kind of -ist that makes me...

By some strange coincidence, a colleague just sent me this article on the 
mathematician John Horton Conway:
http://www.theguardian.com/science/2015/jul/23/john-horton-conway-the-most-charismatic-mathematician-in-the-world

In which is this paragraph:
--
Conway is the rare sort of mathematician whose ability to connect his pet
mathematical interests makes one wonder if he isn't, at some level, shaping 
mathematical reality and not just exploring it, James Propp, a professor of 
mathematics at the University of Massachusetts Lowell, once told me. The 
example of this that I know best is a connection he discovered between sphere 
packing and games. These were two separate areas of study that Conway had 
arrived at by two different paths. So there's no reason for them to be linked. 
But somehow, through the force of his personality, and the intensity of his 
passion, he bent the mathematical universe to his will.
--
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Rustom Mody
On Friday, July 24, 2015 at 2:59:41 AM UTC+5:30, Marko Rauhamaa wrote:
 Chris :
 
  Fortunately, we don't need to completely understand it. New Horizons
  reached Pluto right on time after a decade of flight that involved
  taking a left turn at Jupiter... we can predict exactly what angle to
  fire the rockets at in order to get where we want to go, even without
  knowing how that gravity yank works.
 
  Practicality beats purity?
 
 Engineer!
 
 At the time I was in college I heard topology was very fashionable among
 mathematicians. That was because it was one of the last remaining
 research topics that didn't yet have an application.

Probably shows more than anything else how siloed university depts are:

http://www.amazon.in/Topology-Cambridge-Theoretical-Computer-Science/dp/0521576512
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Rick Johnson
On Thursday, July 23, 2015 at 7:08:10 PM UTC-5, Grant Edwards wrote:
 You can always pick out the topologist at a conference:
 he's the one trying to dunk his coffee cup in his
 doughnut.
 
 [Hey, how often do you get to use a topology  joke.]

Don't sale yourself short Grant. You get extra bonus points
here: (1) told a rare joke and (2) perpetuated the off topic
ramblings in an effort to deflect from main subject. Nice
multitasking dude!




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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Paul Rubin
Grant Edwards invalid@invalid.invalid writes:
 You can always pick out the topologist at a conference: he's the one
 trying to dunk his coffee cup in his doughnut.
 [Hey, how often do you get to use a topology  joke.]

Did you hear about the idiot topologist?  He couldn't tell his butt from
a hole in the ground, but he *could* tell his butt from two holes in the
ground.
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Rick Johnson
On Thursday, July 23, 2015 at 9:03:15 PM UTC-5, Paul Rubin wrote:
 Did you hear about the idiot topologist?  He couldn't tell his butt from
 a hole in the ground, but he *could* tell his butt from two holes in the
 ground.

This sounds more like a riddle than a joke. So in other
words: the message passing requires himself in one hole and
a clone of himself in another hole speaking the message
simultaneously?
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Ian Kelly
On Jul 22, 2015 9:46 PM, Steven D'Aprano 
steve+comp.lang.pyt...@pearwood.info wrote:

 On Thursday 23 July 2015 04:09, Rustom Mody wrote:

  tl;dr To me (as unprofessional a musician as mathematician) I find it
  arbitrary that Newton *discovered* gravity whereas Beethoven *composed*
  the 9th symphony.

 Newton didn't precisely *discover* gravity. I'm pretty sure that people
 before him didn't think that they were floating through the air
 weightless...

 *wink*


 Did gravity exist before Newton? Then he discovered it (in some sense).

 Did the 9th Symphony exist before Beethoven? No? Then he composed it.

Gravity existed before Newton, but the *theory* of gravity did not, so he
composed the theory?
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Chris Angelico
On Fri, Jul 24, 2015 at 6:59 AM, Marko Rauhamaa ma...@pacujo.net wrote:
 Ian Kelly ian.g.ke...@gmail.com:

 Gravity existed before Newton, but the *theory* of gravity did not, so
 he composed the theory?

 Ironically, gravity is maybe the least well understood phenomenon in
 modern physics.

Fortunately, we don't need to completely understand it. New Horizons
reached Pluto right on time after a decade of flight that involved
taking a left turn at Jupiter... we can predict exactly what angle to
fire the rockets at in order to get where we want to go, even without
knowing how that gravity yank works.

Practicality beats purity?

ChrisA
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Gregory Ewing

Rustom Mody wrote:
Ive known good ones) most practicing-mathematicians proceed on the assumption 
that they *discover* math and not that they *invent* it.


For something purely abstract like mathematics, I don't
see how there's any distinction between discovering and
inventing. They're two words for the same thing.

I don't know what kind of -ist that makes me...

--
Greg
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Rustom Mody
On Thursday, July 23, 2015 at 12:28:19 PM UTC+5:30, Gregory Ewing wrote:
 Rustom Mody wrote:
  Ive known good ones) most practicing-mathematicians proceed on the 
  assumption 
  that they *discover* math and not that they *invent* it.
 
 For something purely abstract like mathematics, I don't
 see how there's any distinction between discovering and
 inventing. They're two words for the same thing.
 
 I don't know what kind of -ist that makes me...

Ummm... Clever!
You give few clues... except for 'purely abstract'.
Does that mean entirely in your consciousness?
Or does it mean completely independent of the (physical) world and even time.
Latter is more or less definition of platonist
Former is some kind of combo of intuitionist and formalist (I guess!).

JFTR: I believe that post-Cantor 'platonism' is an abuse of Plato's original
https://en.wikipedia.org/wiki/Allegory_of_the_Cave
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-23 Thread Marko Rauhamaa
Steven D'Aprano st...@pearwood.info:

 I think that we can equally choose the natural numbers to be
 axiomatic, or sets to be axiomatic and derive natural numbers from
 them. Neither is more correct than the other.

Mathematicians quit trying to define what natural numbers mean and just
chose a standard enumerable sequence as *the* set of natural numbers.
That's analogous to physicists defining the meter as a particular rod in
a vault in Paris. So not even the length of the rod but the rod itself.

To modern mathematicians, the concept three simply means the fourth
element in the standard enumeration. When mathematicians need to use
natural numbers to count, they have to escape to predicate logic. For
example, to express that a natural number n has precisely two divisors,
you have to say,

   ∃x∈N ∃y∈N ¬x=y ∧ x|n ∧ y|n

(which avoids counting) or:

   ∃B∈P({x∈N : x|n}×2)
 (∀x∈{x∈N : x|n} ∃y∈2 ((x,y)∈B ∧ ∀z∈2 (x,z)∈B→y=z) ∧
  ∀x∈2 ∃y∈{x∈N : x|n} ((y,x)∈B ∧ ∀z∈{x∈N : x|n} (z,x)∈B→y=z))

This latter clumsy expression captures the notion of counting. However,
in programming terms, you could say counting is not first-class in
mathematics. Counting is done as a macro if you will.

If the logicians had managed to define natural numbers the way they
wanted, counting would be first class and simple:

   {x∈N : x|n}∈2


Marko
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-22 Thread Laura Creighton
One way to look at this is to see that arithmetic is _behaviour_.
Like all behaviours, it is subject to reification:
see: https://en.wikipedia.org/wiki/Reification

and especially as it is done in the German language, reification has
this nasty habit of turning behaviours (i.e. things that are most like
a verb) into nouns, or things that require nouns.  Even the word
_behaviour_ is suspect, as it is a noun. 

This noun-making can be contagious  if we thought of the world, not
as a thing, but happening-now (and see how hard it is to not have
a noun like 'process' there) would we come to the question of 'Who
made it?'  For there would be no 'it' there to point at.

It is not too surprising that the mathematicians have run into the
limits of reification.  There is only so much 'pretend this is a
thing' you can do under relentless questioning before the 'thing-ness'
just goes away ...

Laura
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-22 Thread Steven D'Aprano
On Thu, 23 Jul 2015 02:58 am, Steven D'Aprano wrote:

 1. We have reason to expect that the natural numbers are absolutely
 fundamental and irreducible
 
 That's wrong. If we had such a reason, we could state it: the reason we
 expect natural numbers are irreducible is ... and fill in the blank. But
 I don't believe that such a reason exists (or at least, as far as we
 know).

Sorry, that's not as clear as I intended. By a reason, I mean a direct
reason for that choice, rather than some reason for the opposite choice. I
hope that's clear? Perhaps an example will help.

Are tomatoes red?

We can have direct reasons for believing that tomatoes are red, e.g. the
light reflecting off these tomatoes peaks at frequency X, which is within
the range of red light. 

Alternatively, we might not have any such reason, and be reduced to arguing
against the alternatives. Only if all the alternatives are false could we
then believe that tomatoes are red.

If tomatoes were blue, they would appear green when viewed under yellow
light; since these tomatoes fail to appear green, they might be red.

I'm suggesting that we have no direct reason for believing that the natural
numbers are irreducible concepts, only indirect ones, namely that all the
attempts to reduce them are unsatisfactory in some fashion or another. But
neither do we have direct reasons for expecting them to be reducible.


-- 
Steven

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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-22 Thread Rustom Mody
On Wednesday, July 22, 2015 at 11:22:57 PM UTC+5:30, Oscar Benjamin wrote:
 On Wed, 22 Jul 2015 at 18:01 Steven D'Aprano st...@pearwood.info wrote:
 
 
 
 I think that the critical factor there is that it is all in the past tense.
 
 Today, I believe, the vast majority of mathematicians fall into two camps:
 
 
 
 (1) Those who just use numbers without worrying about defining them in some
 
 deep or fundamental sense;
 
 
 
 Probably. I'd say that worrying too much about the true essence of numbers is 
 just Platonism. Numbers are a construct (a very useful one). There are many 
 other constructs used within mathematics and there are numerous ways to 
 connect them or define them in terms of each other. Usually these are 
 referred to as connections or sometimes more formally as isomorphisms and 
 they can be useful but don't need to have any metaphysical meaning.

Philosophers-of-mathematics decry platonism.
However from my experience (I am not a professional mathematician, though
Ive known good ones) most practicing-mathematicians proceed on the assumption 
that they *discover* math and not that they *invent* it.
To me this says that though they may not know the meaning or spelling of 
platonism, they all layman-adhere to it.

tl;dr To me (as unprofessional a musician as mathematician) I find it arbitrary
that Newton *discovered* gravity whereas Beethoven *composed* the 9th symphony.
Maybe Beethoven was sent my God to write Ode-to-Joy and reunite Europe?
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-22 Thread Rustom Mody
Nice Thanks for that Laura!
I am reminded of

| The toughest job Indians ever had was explaining to the whiteman who their 
| noun-god is. Repeat. That's because God isn't a noun in Native America.
| God is a verb!
From http://hilgart.org/enformy/dma-god.htm

On Wednesday, July 22, 2015 at 10:48:38 PM UTC+5:30, Laura Creighton wrote:
 One way to look at this is to see that arithmetic is _behaviour_.
 Like all behaviours, it is subject to reification:
 see: https://en.wikipedia.org/wiki/Reification

This is just a pointer to various disciplines/definitions...
Which did you intend?
By and large (for me, a CSist) I regard reification as philosophicalese for
what programmers call first-classness.
As someone brought up on Lisp and FP, was trained to regard 
reification/firstclassness
as wonderful.  However after seeing the overwhelming stupidity of 
OOP-treated-as-a-philosophy,
Ive become suspect of this.
If http://steve-yegge.blogspot.in/2006/03/execution-in-kingdom-of-nouns.html
was just a joke it would be a laugh. I believe it is an accurate description
of the brain-pickling it does to its religious adherents.
And so now I am suspect of firstclassness in FP as well:
http://blog.languager.org/2012/08/functional-programming-philosophical.html
(last point)

 
 and especially as it is done in the German language, reification has
 this nasty habit of turning behaviours (i.e. things that are most like
 a verb) into nouns, or things that require nouns.  Even the word
 _behaviour_ is suspect, as it is a noun. 
 
 This noun-making can be contagious  if we thought of the world, not
 as a thing, but happening-now (and see how hard it is to not have
 a noun like 'process' there) would we come to the question of 'Who
 made it?'  For there would be no 'it' there to point at.
 
 It is not too surprising that the mathematicians have run into the
 limits of reification.  There is only so much 'pretend this is a
 thing' you can do under relentless questioning before the 'thing-ness'
 just goes away ...

Yes but one person's threshold where thing-ness can be far away from another's.
Newton used thingness of ∞ (infinitesimals) with impunity and invented calculus.
Gauss found this very improper and re-invented calculus without 'completed 
infinity'.
Yet mathematicians habitually find that, for example generating functions that
are obviously divergent (∴ semantically meaningless) are perfectly serviceable
to solve recurrences; solutions which can subsequently be verified without the
generating functions.
Which side should be embarrassed?
-- 
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-22 Thread Laura Creighton
In a message of Wed, 22 Jul 2015 10:49:13 -0700, Rustom Mody writes:
Nice Thanks for that Laura!
I am reminded of

| The toughest job Indians ever had was explaining to the whiteman who their 
| noun-god is. Repeat. That's because God isn't a noun in Native America.
| God is a verb!
From http://hilgart.org/enformy/dma-god.htm

On Wednesday, July 22, 2015 at 10:48:38 PM UTC+5:30, Laura Creighton wrote:
 One way to look at this is to see that arithmetic is _behaviour_.
 Like all behaviours, it is subject to reification:
 see: https://en.wikipedia.org/wiki/Reification

This is just a pointer to various disciplines/definitions...
Which did you intend?

I meant -- depending on your background -- go find a meaning for
reification that makes sense to you.  And then extend this to some
other areas.

By and large (for me, a CSist) I regard reification as philosophicalese for
what programmers call first-classness.

Me too.  But there are more people out there who know something about
reification than there are that know about first classness.

As someone brought up on Lisp and FP, was trained to regard 
reification/firstclassness
as wonderful.  However after seeing the overwhelming stupidity of 
OOP-treated-as-a-philosophy,
Ive become suspect of this.

If http://steve-yegge.blogspot.in/2006/03/execution-in-kingdom-of-nouns.html
was just a joke it would be a laugh. I believe it is an accurate description
of the brain-pickling it does to its religious adherents.
And so now I am suspect of firstclassness in FP as well:
http://blog.languager.org/2012/08/functional-programming-philosophical.html
(last point)

 
 and especially as it is done in the German language, reification has
 this nasty habit of turning behaviours (i.e. things that are most like
 a verb) into nouns, or things that require nouns.  Even the word
 _behaviour_ is suspect, as it is a noun. 
 
 This noun-making can be contagious  if we thought of the world, not
 as a thing, but happening-now (and see how hard it is to not have
 a noun like 'process' there) would we come to the question of 'Who
 made it?'  For there would be no 'it' there to point at.
 
 It is not too surprising that the mathematicians have run into the
 limits of reification.  There is only so much 'pretend this is a
 thing' you can do under relentless questioning before the 'thing-ness'
 just goes away ...

Yes but one person's threshold where thing-ness can be far away from another's.
Newton used thingness of ∞ (infinitesimals) with impunity and invented 
calculus.
Gauss found this very improper and re-invented calculus without 'completed 
infinity'.
Yet mathematicians habitually find that, for example generating functions that
are obviously divergent (∴ semantically meaningless) are perfectly serviceable
to solve recurrences; solutions which can subsequently be verified without the
generating functions.
Which side should be embarrassed?

Embarassment is a function of the ego.  The ego is _another_ one of those nouns
where if you try to stalk it, it falls apart because it was produced by
behaviour, rather than the cause of behaviour.

Descartes:  I think, therefore I am.  (Because there must be an I that is
doing the thinking.)

Modern Day Western Neurologist:  Thinking is going on.  Therefore an I is
produced.

Laura

-- 
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OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-22 Thread Steven D'Aprano
On Wed, 22 Jul 2015 11:34 pm, Rustom Mody wrote:

 On Tuesday, July 21, 2015 at 4:09:56 PM UTC+5:30, Steven D'Aprano wrote:
 
 We have no reason to expect that the natural numbers are anything less
 than absolutely fundamental and irreducible (as the Wikipedia article
 above puts it). It's remarkable that we can reduce all of mathematics to
 essentially a single axiom: the concept of the set.
 
 These two statements above contradict each other.
 With the double-negatives and other lint removed they read:

I meant what I said.

 1. We have reason to expect that the natural numbers are absolutely
 fundamental and irreducible

That's wrong. If we had such a reason, we could state it: the reason we
expect natural numbers are irreducible is ... and fill in the blank. But I
don't believe that such a reason exists (or at least, as far as we know).

However, neither do we have any reason to think that they are *not*
irreducible. Hence, we have no reason to think that they are anything but
irreducible.


 2. We can reduce all of mathematics to essentially a single axiom: the
 concept of the set.

Heh, yes, that is a bit funny. But I don't think it's really a
contradiction, because I don't think that numbers really are sets.

The set-theoretic definition of the natural numbers is quite nice, but is it
really simpler than the old fashioned idea of natural numbers as counting
numbers? Certainly it shows that we have a one-to-one correspondence from
the natural numbers to sets, building from the empty set alone, and in some
sense sets seem more primitive. But I think that proving that sets actually
are more primitive is another story.

I think that we can equally choose the natural numbers to be axiomatic, or
sets to be axiomatic and derive natural numbers from them. Neither is more
correct than the other.

By the way, my comment about essentially a single axiom should be read
informally. Formally, you need a whole bunch of axioms:

http://math.stackexchange.com/questions/68659/set-theoretic-construction-of-the-natural-numbers

I stated that the set-theoretic definition was generally accepted, but
that's quite far from saying it is logically proven. The definition comes
from Zermelo–Fraenkel set theory (ZF) plus the Axiom of Choice (ZFC), but
the Axiom of Choice is not uncontroversial. E.g. the  Banach-Tarski paradox
follows from AC.

https://en.wikipedia.org/wiki/Banach%E2%80%93Tarski_paradox

Like any other Axiom, the Axiom of Choice is unprovable. You can either
accept it or reject it, and there is also ZF¬C. Jerry Bona jokes:

The Axiom of Choice is obviously true, the well-ordering principle
obviously false, and who can tell about Zorn's lemma?

the joke being that all three are mathematically equivalent.


 So are you on the number-side -- Poincare, Brouwer, Heyting...
 Or the set-side -- Cantor, Russel, Hilbert... ??

Yes. I think both points of view are useful, even if only useful in
understanding what the limits of that view are.


 On Tuesday 21 July 2015 19:10, Marko Rauhamaa wrote:
  Our ancestors defined the fingers (or digits) as the set of numbers.
  Modern mathematicians have managed to enhance the definition
  quantitatively but not qualitatively.
 
 So what?
 
 This is not a problem for the use of numbers in science, engineering or
 mathematics (including computer science, which may be considered a branch
 of all three). There may be still a few holdouts who hope that Gödel is
 wrong and Russell's dream of being able to define all of mathematics in
 terms of logic can be resurrected, but everyone else has moved on, and
 don't consider it to be an embarrassment any more than it is an
 embarrassment that all of philosophy collapses in a heap when faced with
 solipsism.
 
 That's a bizarre view.

Really? Which part(s) do you consider bizarre?

(1) That the lack of any fundamental definition of numbers in terms is not a
problem in practice?

(2) That comp sci can be considered a branch of science, engineering and
mathematics?

(3) That there may still be a few people who hope Gödel is wrong?

(4) That everyone else (well, at least everyone else in mathematics, for
some definition of everyone) has moved on?

(5) That philosophy is unable to cope with the problem of solipsism?


I don't think any of those statements are *bizarre*, i.e. conspicuously or
grossly unconventional or unusual; eccentric; freakish; gonzo; outlandish;
outre; grotesque.

In hindsight, my claim of everyone else having moved on is too strong --
there are millions of mathematicians in the world, and I'm sure that you
can find one or two who don't fall into either of the two categories I
gave. That is, they neither wish to dispute Gödel nor do they accept the
irreducibility of numbers as something matter-of-fact and not embarrassing.
So let's just quietly insert an almost before everyone and move on,
shall we?


 As a subjective view I dont feel embarrassed by... its not arguable
 other than to say embarrassment is like 

Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-22 Thread Paul Rubin
Steven D'Aprano st...@pearwood.info writes:
 That's wrong. If we had such a reason, we could state it: the reason
 we expect natural numbers are irreducible is ... and fill in the
 blank. But I don't believe that such a reason exists (or at least, as
 far as we know).

 However, neither do we have any reason to think that they are *not*
 irreducible. Hence, we have no reason to think that they are anything
 but irreducible.

But by the same reasoning, we have no reason to think they are anything
but non-irreducible (reducible, I guess).  What the heck does it mean
for a natural number to be irreducible anyway?  I know what it means for
a polynomial to be irreducable, but the natural number analogy would be
a composite number, and there are plenty of those.

You might like this:

https://web.archive.org/web/20110806055104/http://www.math.princeton.edu/~nelson/papers/hm.pdf

Remember also that in ultrafinitism, Peano Arithmetic goes from 1 to
88 (due to Shachaf on irc #haskell).  ;-)
-- 
https://mail.python.org/mailman/listinfo/python-list


Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-22 Thread Oscar Benjamin
On Wed, 22 Jul 2015 at 18:01 Steven D'Aprano st...@pearwood.info wrote:


 I think that the critical factor there is that it is all in the past tense.
 Today, I believe, the vast majority of mathematicians fall into two camps:

 (1) Those who just use numbers without worrying about defining them in some
 deep or fundamental sense;


Probably. I'd say that worrying too much about the true essence of numbers
is just Platonism. Numbers are a construct (a very useful one). There are
many other constructs used within mathematics and there are numerous ways
to connect them or define them in terms of each other. Usually these are
referred to as connections or sometimes more formally as isomorphisms
and they can be useful but don't need to have any metaphysical meaning.

Conventional mathematics treats the natural numbers as subsets of the
complex numbers and usually treats the complex numbers as the most basic
type of numbers. Exactly how you construct this out of sets is not as
important as the usefulness of this concept when actually trying to use
numbers.

(2) Those who understand Gödel and have given up or rejected Russell's
 program to define mathematics in terms of pure logic.

snip

 It's that I think that Russell's program is a degenerate research program
 and irrelevant paradigm abandoned by nearly everyone. Not only does Gödel
 prove the impossibility of Russell's attempt to ground mathematics in pure
 logic, but mathematicians have by and large rejected Russell's paradigm as
 irrelevant, like quintessence or aether to physicists, or how many angels
 can dance on the head of a pin to theologians. In simple terms, hardly
 anyone cares how you define numbers, so long as the definition gives you
 arithmetic.


Actually in the decades since the incompleteness theorems were published
much of mathematics has simply ignored the problem. Hilbert's idea to
construct everything out of formal systems of axioms and proof rules
continues to be pushed to its limits. This is now a standard approach in
the literature, in textbooks and published papers, and in undergraduate
programs. In contrast Gödel's (Platonist IMO) intuitionist idea of
mathematical proof is ignored.

The thing is that it turns out that even if you can't prove everything then
you can at least prove a lot: Gödel demonstrated the existence of at least
one unprovable theorem. Since we know that there are loads of unproven
theorems and that loads of them continue to be proven all the time we
clearly haven't yet hit any kind of Gödel limit that would impede further
progress.


 Quoting Wikipedia:

 In the years following Gödel's theorems, as it became clear that there is
 no hope of proving consistency of mathematics, and with development of
 axiomatic set theories such as Zermelo–Fraenkel set theory and the lack of
 any evidence against its consistency, most mathematicians lost interest in
 the topic.


They lost interest in the topic of proving consistency, completeness etc.
They didn't lose interest in creating an explosion of different sets of
axioms and proof systems, studying the limits of each and trying to push as
much of conventional mathematics as possible into grand frameworks.

For a modern example of Hilbert's legacy take a look at these guys:

http://us.metamath.org/mpegif/mmtheorems.html

They've tried to construct all of mathematics out of set theory using a
fully formal (computer verifiable) proof database. They define the natural
numbers as a subset of the complex numbers:

http://us.metamath.org/mpegif/mmtheorems87.html#mm8625s

The complex numbers themselves are defined in terms of the ordinal numbers
which are similar to the natural numbers but have a distinct definition in
terms of sets:

http://us.metamath.org/mpegif/mmtheorems77.html#mm7635s

I think they did it that way because it's just too awkward if the complex
number 1 isn't the same as the natural number 1.

--
Oscar
-- 
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-22 Thread Rustom Mody
On Wednesday, July 22, 2015 at 11:18:23 PM UTC+5:30, Paul Rubin wrote:
 Remember also that in ultrafinitism, Peano Arithmetic goes from 1 to
 88 (due to Shachaf on irc #haskell).  ;-)

No No No
Its 42; Dont you know?
-- 
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Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-22 Thread Rustom Mody
On Tuesday, July 21, 2015 at 4:09:56 PM UTC+5:30, Steven D'Aprano wrote:

 We have no reason to expect that the natural numbers are anything less than 
 absolutely fundamental and irreducible (as the Wikipedia article above 
 puts it). It's remarkable that we can reduce all of mathematics to 
 essentially a single axiom: the concept of the set.

These two statements above contradict each other.
With the double-negatives and other lint removed they read:

1. We have reason to expect that the natural numbers are absolutely fundamental 
and irreducible

2. We can reduce all of mathematics to essentially a single axiom: the concept 
of the set.

So are you on the number-side -- Poincare, Brouwer, Heyting...
Or the set-side -- Cantor, Russel, Hilbert... ??

 On Tuesday 21 July 2015 19:10, Marko Rauhamaa wrote:
  Our ancestors defined the fingers (or digits) as the set of numbers.
  Modern mathematicians have managed to enhance the definition
  quantitatively but not qualitatively.
 
 So what?
 
 This is not a problem for the use of numbers in science, engineering or 
 mathematics (including computer science, which may be considered a branch of 
 all three). There may be still a few holdouts who hope that Gödel is wrong 
 and Russell's dream of being able to define all of mathematics in terms of 
 logic can be resurrected, but everyone else has moved on, and don't consider 
 it to be an embarrassment any more than it is an embarrassment that all of 
 philosophy collapses in a heap when faced with solipsism.

That's a bizarre view.
As a subjective view I dont feel embarrassed by... its not arguable other than
to say embarrassment is like thick-skinnedness -- some have elephant-skins 
some have gossamer skins

As an objective view its just wrong: Eminent mathematicians have disagreed
so strongly with each other as to what putative math is kosher and what 
embarrassing that they've sent each other to mental institutions.

And -- most important of all -- these arguments are at the root of why CS 
'happened' : http://blog.languager.org/2015/03/cs-history-0.html

The one reason why this view -- the embarrassments in math/logic foundations 
are no longer relevant as they were in the 1930s -- is because people think
CS is mostly engineering, hardly math. So (the argument runs) just as general 
relativity is irrelevant to bridge-building, so also meta-mathematics is to 
pragmatic CS.

The answer to this view -- unfortunately widely-held -- is the same as above:
http://blog.languager.org/2015/03/cs-history-0.html
A knowledge of the history will disabuse of the holder of these 
misunderstandings
and misconceptions
-- 
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-22 Thread Chris Angelico
On Thu, Jul 23, 2015 at 11:44 AM, Dennis Lee Bieber
wlfr...@ix.netcom.com wrote:
 On Thu, 23 Jul 2015 03:21:24 +1000, Steven D'Aprano st...@pearwood.info
 declaimed the following:


Are tomatoes red?

 In answer I offer a novel: /Fried Green Tomatoes at the Whistle Stop
 Cafe/ (and lots of recipes for such on Google)

I think we can take it as red.

*dives for cover*

ChrisA
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-22 Thread Steven D'Aprano
On Thursday 23 July 2015 03:48, Paul Rubin wrote:

 Steven D'Aprano st...@pearwood.info writes:
 That's wrong. If we had such a reason, we could state it: the reason
 we expect natural numbers are irreducible is ... and fill in the
 blank. But I don't believe that such a reason exists (or at least, as
 far as we know).

 However, neither do we have any reason to think that they are *not*
 irreducible. Hence, we have no reason to think that they are anything
 but irreducible.
 
 But by the same reasoning, we have no reason to think they are anything
 but non-irreducible (reducible, I guess).  What the heck does it mean
 for a natural number to be irreducible anyway?  

Reducible in the sense that we can define the natural numbers in terms of a 
simpler concept. E.g. the rationals can be reduced to the quotient of 
integers. One might argue that defining them in terms of sets is precisely 
that, but then we get into an argument as to which is simpler, natural 
numbers or sets?



-- 
Steve

-- 
https://mail.python.org/mailman/listinfo/python-list


Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-22 Thread Steven D'Aprano
On Thursday 23 July 2015 04:09, Rustom Mody wrote:

 tl;dr To me (as unprofessional a musician as mathematician) I find it
 arbitrary that Newton *discovered* gravity whereas Beethoven *composed*
 the 9th symphony.

Newton didn't precisely *discover* gravity. I'm pretty sure that people 
before him didn't think that they were floating through the air 
weightless... 

*wink*


Did gravity exist before Newton? Then he discovered it (in some sense).

Did the 9th Symphony exist before Beethoven? No? Then he composed it.


-- 
Steve

-- 
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Re: OT Re: Math-embarrassment results in CS [was: Should non-security 2.7 bugs be fixed?]

2015-07-22 Thread Mark Lawrence

On 22/07/2015 19:14, Laura Creighton wrote:

I don't suppose anybody could spare a bit of time for something that is 
slightly more important IMHO, like getting the core workflow going?


I'm fairly well convinced that the vast majority of people here aren't 
in the slightest bit interested in actually doing anything, but just in 
case you could try reading.


https://www.python.org/dev/peps/pep-0462/
https://www.python.org/dev/peps/pep-0474/

--
My fellow Pythonistas, ask not what our language can do for you, ask
what you can do for our language.

Mark Lawrence

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