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Re: Erroneous conclusions from applying material conditionals?

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On Thursday, June 1, 2023 at 9:13:38 PM UTC-7, Dan Christensen wrote:
> On Thursday, June 1, 2023 at 10:55:02 PM UTC-4, Ross Finlayson wrote: 
> > On Thursday, June 1, 2023 at 6:54:14 PM UTC-7, Dan Christensen wrote: 
> > > On Tuesday, May 30, 2023 at 1:53:36 AM UTC-4, Ross Finlayson wrote: 
> > > 
> > > [snip] 
> 
> > > > So, your wonderings about "is there something wrong with material implication?" can be deliberated 
> > > > in an expansive sense by understanding that "the logics" you've been copying have a "the baggage" 
> > > > that is about the algorithmics, the rules, whether there are multiple observers or parallel change, 
> > > > and then other things that get into what are suitable systems for the evaluation of inference, 
> > > > in what are "time-forward" systems and with monotonicity and modality. 
> > > > 
> > > [snip] 
> > > 
> > > My concern is about conditional statements based on logical propositions that are unambiguously either true or false in the PRESENT--the case of false antecedents in particular. I take it you reject the notion that if proposition A is false, then the implication A=>B (but not necessarily B) must be true. ~A=>[A=>B] 
> > > 
> > > My proof again: 
> > > 
> > > 1. ~A 
> > > Premise 
> > > 
> > > 2. A 
> > > Premise 
> > > 
> > > 3. ~B 
> > > Premise 
> > > 
> > > 4. ~A & A 
> > > Join, 1, 2 
> > > 
> > > 5. ~~B 
> > > Conclusion, 3 
> > > 
> > > 6. B 
> > > Rem DNeg, 5 
> > > 
> > > 7. A => B 
> > > Conclusion, 2 
> > > 
> > > 8. ~A => [A => B] 
> > > Conclusion, 1 
> > > 
> > > Please explain why you take exception to this when, as you must know, the vast majority of mathematicians accept this method of proof to no ill effect, i.e. no logical inconsistencies or errors.
> > There you just change the order of 1 and 2. 
> > 
> > 
> > 
> > You're just fabricating any contradiction and using it to negate the next step 
> > in the proof you've ordered: it's not logic, it's stipulation. 
> >
> [snip] 
> 
> Apparently you cannot point to any actual errors arising from the application these methods. We know they work.
> Dan 
> 
> Download my DC Proof 2.0 freeware at http://www.dcproof.com 
> Visit my Math Blog at http://www.dcproof.wordpress.com

A stopped clock is, right twice a day.

About the most usual modal or temporal is day or night, 
for something like "everything falls" there's "the sun also rises", 
but at any given time it's A or ~A and 50:50 whether it's so.

So of course, with direct implication, you can plug in, according to 
whether it's day or night, A or ~A respectively, to all the inferences, 
that go into all the derivation rules, in all their completions, 
what derives what's coincident and after what's causal, and 
all such good of logic, results right, without, re-write, 
while "material implication" would simply result having to 
re-write all the derivations, and, toss the old ones, 
and, any information contained in them as single point of definition, 
would not exist, it would be, lost.

So, first, I don't need "material implication" for anything, _and neither 
does anybody else_, except for a particular sort of data structure where it 
makes entailment trivial for the monotonicity of concatenation, assuming 
of course no two premises were ever introduced twice and discharged variously, 
where, it's as well just left out in an equivalent data structure with a convention for 
a null, for the very "absurdity" in its absence of implication.

That's convenient and a convention in a data structure in a space of 
values, these days we're not quite so short bits and it's more relevant often 
to update the structure besides reading it off, mand it's just as fast with 
"direct implication" and making for "monotonicity of concatenation".
(Including for example discovering "non-monotinincity of concatenatation".)

Now, I can understand that's very widespread, but also that most people 
have never gone into the derivations, where what would be the "completion", 
brings in the necessity of an ontological commitment _in the derivation_ what 
must be _in the logic_, to universal quantification and such.  I.e. it breaks 
there, like I said above.

Also, I can understand that's very widespread, but most people do not use 
it at all, because to them it says "a lie implies my truth" which is not reasonable
to these people, and instead they use "really:  classical propositional calculus".


Then, about the order of your premises, and their discharge, 
why can't you re-order your premises?  Is it because the order 
you've declared them makes a stipulation with no common 
terms another stipulation that they do have a common term 
only being in the order you've declared them?


Are you suggesting that stipulations with no common terms are related?

It seems moreso that _you must stipulate it_ and then 
it's up to you to show it non-contadictory, which is problematic, 
when _you must also prove it implies the opposite_, 
that _the both things it implies contradict each other_.

Though, I'd imagine you'd rather leave that out, ..., 
then that in larger systems it gets more and more intractable 
to maintain correctness when things change, 
because "material" "implication" should be two 
things:  1) direct implication, and 2) a placeholder under 
the vacuous, that when someone adds columns to "the truth table" 
with derived quantites expected to be used in the arithmetic 
of the maintenance of data structure, because that's all the 
way of this is for its "monotonic concatenation entailing entailment", 
that part is "not an inference" just "keeping the projection in the space".


Are you suggesting that stipulations with no common terms are related, 
and you can negate them capriciously just be stipulating a contradiction first?

Because, that's just stipulating "this is logical, now forget it", 
really, I think best you can do is make "material implication" 
a premise and then separate out the parts for direct implication 
contra "vacuous placeholder".


So, I definitely point at "showing a contradiction in terms 
negates an unrelated term" as _false_.

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Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-27 12:04 -0700
  Re: Erroneous conclusions from applying material conditionals? Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-05-27 13:25 -0700
    Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-27 19:42 -0700
  Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-28 08:39 -0700
    Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-28 11:50 -0700
    Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-28 12:01 -0700
      Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-28 13:47 -0700
        Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-28 13:57 -0700
          Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-28 14:02 -0700
          Re: Erroneous conclusions from applying material conditionals? olcott <polcott2@gmail.com> - 2023-05-28 16:12 -0500
          Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-28 15:39 -0700
            Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-28 15:56 -0700
              Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-28 16:04 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-28 16:14 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-28 16:24 -0700
              Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-28 16:49 -0700
              Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-28 16:52 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <janburse@fastmail.fm> - 2023-05-29 02:25 +0200
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <janburse@fastmail.fm> - 2023-05-29 02:31 +0200
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <janburse@fastmail.fm> - 2023-05-29 02:45 +0200
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-28 17:59 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-28 17:46 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-28 17:51 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-28 18:01 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-28 18:07 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-28 18:12 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-28 18:15 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-28 18:17 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-28 18:23 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-28 18:28 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-28 18:46 -0700
                Re: Erroneous conclusions from applying material conditionals? Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-05-28 21:51 -0700
                Re: Erroneous conclusions from applying material conditionals? Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-05-28 22:14 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-28 22:33 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-28 22:36 -0700
                Re: Erroneous conclusions from applying material conditionals? Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-05-29 09:01 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-29 09:27 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-29 09:32 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-29 09:35 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-29 10:03 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <janburse@fastmail.fm> - 2023-05-29 19:45 +0200
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-30 05:52 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-30 15:16 -0700
                Re: Erroneous conclusions from applying material conditionals? Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-05-29 11:14 -0700
                Re: Erroneous conclusions from applying material conditionals? Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-05-29 22:53 -0700
                Re: Erroneous conclusions from applying material conditionals? Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-05-30 17:45 -0700
                Re: Erroneous conclusions from applying material conditionals? Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-05-31 08:23 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-31 13:22 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-31 13:31 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-31 13:38 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-31 13:51 -0700
                Re: Erroneous conclusions from applying material conditionals? Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-06-01 19:56 -0700
                Re: Erroneous conclusions from applying material conditionals? Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-06-01 21:35 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-06-01 21:44 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-06-01 18:54 -0700
                Re: Erroneous conclusions from applying material conditionals? Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-06-01 19:55 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-06-01 21:13 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-06-01 21:19 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-06-01 21:23 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-06-01 21:30 -0700
                Re: Erroneous conclusions from applying material conditionals? Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-06-01 22:02 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-06-01 22:28 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-06-01 22:31 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-06-01 22:34 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-06-01 22:39 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-06-01 23:29 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-06-03 14:14 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-06-03 14:23 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-06-01 23:26 -0700
                Re: Erroneous conclusions from applying material conditionals? Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-06-02 09:42 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-06-01 20:41 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-06-01 20:58 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-06-01 21:24 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-06-01 21:28 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-06-01 21:31 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-06-01 21:34 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-06-01 22:49 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-06-03 04:49 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-06-03 04:51 -0700
        Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-28 15:33 -0700
    Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-29 02:52 -0700
      Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-29 02:58 -0700
        Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-29 03:03 -0700
          Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-29 07:35 -0700
            Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-29 08:23 -0700
              Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-29 08:30 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-29 08:33 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-29 09:56 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <janburse@fastmail.fm> - 2023-05-29 19:56 +0200
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-29 11:40 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-29 11:43 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-29 13:32 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-29 13:38 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-29 13:59 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-29 15:19 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-29 15:21 -0700
                Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-05-29 17:37 -0700
                Re: Erroneous conclusions from applying material conditionals? Dan Christensen <Dan_Christensen@sympatico.ca> - 2023-05-29 19:00 -0700
  Re: Erroneous conclusions from applying material conditionals? Mild Shock <janburse@fastmail.fm> - 2023-06-02 09:41 +0200
    Re: Erroneous conclusions from applying material conditionals? Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-06-02 09:42 -0700
      Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-06-02 11:00 -0700
        Re: Erroneous conclusions from applying material conditionals? Mild Shock <bursejan@gmail.com> - 2023-06-02 11:14 -0700

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