P=P is a Contradiction

What is the basis for reason? And mathematics?

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Skepdick
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Re: P=P is a Contradiction

Post by Skepdick »

Immanuel Can wrote: Mon Oct 05, 2020 10:15 pm Well, whether that's right depends on whether by "compatible" you mean, "able to get along," or "the same thing."
That depends on what you mean by "same". It's not entirely clear given the existence of logical systems in which P=P is False.
Thus demonstrating that P=P is no "law" of any kind...

Here's such a system:

https://repl.it/repls/DeadDisgustingArt ... telligence

Code: Select all

class Proposition(object):
  def __eq__(self, other):
    if id(self) == id(other):
      return False

P = Proposition()

assert (P == P) == False
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Immanuel Can
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Re: P=P is a Contradiction

Post by Immanuel Can »

Skepdick wrote: Mon Oct 05, 2020 10:36 pm
Immanuel Can wrote: Mon Oct 05, 2020 10:15 pm We have moved too far away from the law of non-contradiction for this to have any relevance to me.
You haven't moved at all... you continue to be as confused as you always were.
I should have said "identity." They're in the same pack of Aristotelian principles, of course. Corrected now.

The original topic was the law of identity.
Skepdick
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Re: P=P is a Contradiction

Post by Skepdick »

Immanuel Can wrote: Mon Oct 05, 2020 10:51 pm
Skepdick wrote: Mon Oct 05, 2020 10:36 pm
Immanuel Can wrote: Mon Oct 05, 2020 10:15 pm We have moved too far away from the law of non-contradiction for this to have any relevance to me.
You haven't moved at all... you continue to be as confused as you always were.
I should have said "identity." They're in the same pack of Aristotelian principles, of course. Corrected now.

The original topic was the law of identity.
So make up your mind.

Is the law or the principle of identity?
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Immanuel Can
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Re: P=P is a Contradiction

Post by Immanuel Can »

Skepdick wrote: Mon Oct 05, 2020 10:55 pm Is the law or the principle of identity?
I did.

We're done.
Skepdick
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Re: P=P is a Contradiction

Post by Skepdick »

Immanuel Can wrote: Mon Oct 05, 2020 10:58 pm We're done.
You are done, indeed.

https://repl.it/repls/MediumpurpleRingedRar

Code: Select all

class Rose:
  def __eq__(self, other):
      return False

P = Rose()

# The "law" that wasn't. 
# A rose is not a rose.
assert (P != P) == True
assert (P == P) == False
Averroes
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Re: P=P is a Contradiction

Post by Averroes »

Immanuel Can wrote: Mon Oct 05, 2020 10:15 pm
Averroes wrote: Mon Oct 05, 2020 9:40 pm I am only adding that mathematics and linguistics are compatible
Well, whether that's right depends on whether by "compatible" you mean, "able to get along," or "the same thing." Yes to the former, no to the latter, of course.
That's great. Indeed, I find that it's important to ascertain the meaning of words. I often find the standard English dictionary to be a useful resource to ascertain the meaning of English words. And from those that I consult, it is not said that the word "compatible" means "the same thing". For the record, the following is what the dictionary I consulted says about the word "compatible":

compatible: capable of existing together in harmony
https://www.merriam-webster.com/dictionary/compatible

So to be a bit more precise than the definition you agreed upon, the compatibility of linguistics and mathematics is more than just being "able to get along" in that they have the "ability to get along harmoniously." Anyway, the actuality of mathematical linguistics already said it all.

Immanuel Can wrote: Mon Oct 05, 2020 10:15 pm
Averroes wrote: Mon Oct 05, 2020 9:40 pmMay I ask you whether you still consider linguistic and mathematics to be incompatible and mutually exclusive?
I didn't say either.
Of course, it goes without saying now as you have just agreed with the compatibility of linguistics and mathematics. But thank you for answering my question nonetheless and confirming your previous agreement. I appreciate it.

Immanuel Can wrote: Mon Oct 05, 2020 10:15 pm But I grow bored of this, and care to invest no more effort into the topic.
In that case, I will not hold your attention any longer after this post and I hope you get over this.

Immanuel Can wrote: Mon Oct 05, 2020 10:15 pm However, for your peace of mind, I note your disagreement, or rather, your partial agreement. And there the matter shall rest.
That's nice of you to take my peace of mind into consideration. But I found that it was a peaceful exchange all along though. And I also found it to be a very interesting sharing of perspectives. You were kind to have answered all my questions except the last ones, just before you abruptly got uneasy. But it's ok, I appreciated the exchange a lot. Thank you for the exchange, and I wish you a healthy recovery.
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Immanuel Can
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Re: P=P is a Contradiction

Post by Immanuel Can »

Averroes wrote: Tue Oct 06, 2020 9:33 am ... just before you abruptly got uneasy.
Heh. You've got your guess at my state of mind wrong, I'm afraid. :D

I'm not at all "uneasy." Just not interested in the topic. It's too far away from the issue of the law of identity, which is the issue over which I entered the thread in the first place. If there was a relevance, or some sort of "win" in making the point here, I'd persist. But there's nothing much to be gained in anything I originally cared about.

We agree on the law of identity, and we did a bit ago. That's fine, because that's the original substance of the "P=P" issue.

Have a nice day.
Eodnhoj7
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Re: P=P is a Contradiction

Post by Eodnhoj7 »

The law of identity can be negated under the Munchauseen Trilemma.

1. P is assumed.
2. P can equivocate to an infinite variety of things: ((((P=P)=Q)=R)...)
3. P=P is circular.
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henry quirk
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Re: P=P is a Contradiction

Post by henry quirk »

Eodnhoj7 wrote: Tue Oct 06, 2020 6:43 pm The law of identity can be negated under the Munchauseen Trilemma.

1. P is assumed.
2. P can equivocate to an infinite variety of things: ((((P=P)=Q)=R)...)
3. P=P is circular.
I got an apple: it is that apple and no other

negate that
Impenitent
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Re: P=P is a Contradiction

Post by Impenitent »

steve made my apple

-Imp
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henry quirk
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Re: P=P is a Contradiction

Post by henry quirk »

Impenitent wrote: Tue Oct 06, 2020 9:50 pm steve made my apple

-Imp
which is your apple and no other: law of, or principle of, identity standin' proud, lamp upraised, welcomin' the poor & tired & philosophical to the shores of Realsville
Eodnhoj7
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Re: P=P is a Contradiction

Post by Eodnhoj7 »

henry quirk wrote: Tue Oct 06, 2020 8:48 pm
Eodnhoj7 wrote: Tue Oct 06, 2020 6:43 pm The law of identity can be negated under the Munchauseen Trilemma.

1. P is assumed.
2. P can equivocate to an infinite variety of things: ((((P=P)=Q)=R)...)
3. P=P is circular.
I got an apple: it is that apple and no other

negate that
The one apple you own at one moment changes to the next, as it decays, thus you are holding multiple different apples.
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henry quirk
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Re: P=P is a Contradiction

Post by henry quirk »

Eodnhoj7 wrote: Wed Oct 07, 2020 12:14 am
henry quirk wrote: Tue Oct 06, 2020 8:48 pm
Eodnhoj7 wrote: Tue Oct 06, 2020 6:43 pm The law of identity can be negated under the Munchauseen Trilemma.

1. P is assumed.
2. P can equivocate to an infinite variety of things: ((((P=P)=Q)=R)...)
3. P=P is circular.
I got an apple: it is that apple and no other

negate that
The one apple you own at one moment changes to the next, as it decays, thus you are holding multiple different apples.
nope...I buy me a juicy red apple, write A on it with a marker, set on my kitchen table, and leave it to rot...a month later, that juicy red apple is dry & withered but the A is clearly visible...it's the same apple, only it's condition has changed
Eodnhoj7
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Re: P=P is a Contradiction

Post by Eodnhoj7 »

henry quirk wrote: Wed Oct 07, 2020 1:07 am
Eodnhoj7 wrote: Wed Oct 07, 2020 12:14 am
henry quirk wrote: Tue Oct 06, 2020 8:48 pm

I got an apple: it is that apple and no other

negate that
The one apple you own at one moment changes to the next, as it decays, thus you are holding multiple different apples.
nope...I buy me a juicy red apple, write A on it with a marker, set on my kitchen table, and leave it to rot...a month later, that juicy red apple is dry & withered but the A is clearly visible...it's the same apple, only it's condition has changed
A phenomenon is inseperable from the conditions through which it exists given conditions are that which define a phenomenon. The "A" you write on a fresh apple differs from the "A" which exists on the rotten apples. "Conditionality" is merely a tautology of "being".
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henry quirk
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Re: P=P is a Contradiction

Post by henry quirk »

Eodnhoj7 wrote: Wed Oct 07, 2020 1:54 am
henry quirk wrote: Wed Oct 07, 2020 1:07 am
Eodnhoj7 wrote: Wed Oct 07, 2020 12:14 am
The one apple you own at one moment changes to the next, as it decays, thus you are holding multiple different apples.
nope...I buy me a juicy red apple, write A on it with a marker, set on my kitchen table, and leave it to rot...a month later, that juicy red apple is dry & withered but the A is clearly visible...it's the same apple, only it's condition has changed
A phenomenon is inseperable from the conditions through which it exists given conditions are that which define a phenomenon. The "A" you write on a fresh apple differs from the "A" which exists on the rotten apples. "Conditionality" is merely a tautology of "being".
total malarky ('course, the Henry Quirk of tomorrow, who, accordin' to you, will not be me, might agree with you)
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