Great comments on new #namethetrait video

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brimstoneSalad
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Re: Great comments on new #namethetrait video

Post by brimstoneSalad »

Margaret Hayek wrote: Mon Dec 04, 2017 8:43 pm I really disagree: the English version, which isn't question-begging, requires that the changes be identity preserving, because the resulting entities which we're supposed not to deem valueless are still supposed to be us / ourselves. Isaac does not realize that by stepping away from this by letting the resulting entities NOT BE US he has altered the argument, robbed it of its rational force, and made it question begging. I think it will be very confusing not to address this AT SOME POINT in the wiki.
I see the point here, and agree that the changes that have been made are important to mention.

I think we should congratulate Isaac for being open to these changes. If he actually makes these changes publicly that would be a strong argument against intellectual dishonesty if he recognizes the issues it fixes... despite the change being more horizontal rather than a definitive improvement to the argument. Any change or admission of mistake, no matter how minor, means a lot.

In terms of how to correct the argument, I think the P3 I mentioned to Daz in the last post would do more to preserve the force of the argument and contribute to validity. Form his comments, this point about double standards seems to be the hidden assumption many of Isaac's followers are making.

The idea that double standards are either ALWAYS acceptable, or ALWAYS wrong... and no notion that somebody could hold a double standard about when/for whom it's OK to have double standards.
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Re: Great comments on new #namethetrait video

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Re: Margaret,
[Margaret: OK, let me take another run at why I think this section is unhelpful, and let me do it this way. In the closest possible world in which NTT establishes anything about non-human animal moral value, it establishes not only that there is no moral value giving trait absent in all sentient non-human animals, but it establishes that all sentient non-human animals have moral value giving traits (e.g. by adding the relevant suppressed premises needed to make it valid). So it is pointless to consider some really far off possible world in it establishes only that there is no moral value giving trait absent in all sentient non-human animals without establishing that all sentient non-human animals have moral value giving traits (how would it even do that? By adding some weird premises that establish the former but not the latter? Why on earth would it ever do that?)]
It's relevant because if the issue is not fixed, the argument is still invalid even with the additional premise. Establishing

that there is no moral value giving trait absent in all sentient non-human animals

only means there is one animal with the moral value giving trait. That is why in the alternate version we have changed P2 from

(P2) ¬∃t ( T(t) ∧ ∀x ( A(x) ⇒ ¬P(x,t) ) ∧ ∀y ( ( CP(y) ∧ ¬P(y,t) ) ⇒ ¬ M(y) ) )

to

(P2) ∀x ( A(x) ⇒ ( ∃y ( CP(y) ∧ M(y) ∧ ∀t ( T(t) ⇒ ( P(x,t) ⇔ P(y,t) ) ) ) ) )

Without talking about the quantification issue, there is no explanation as to why we would have done this.

Also, regarding the article, I added in some stuff about essential properties, part 2 and changed the conclusion

Edit: Added a correction, do we think it is valid?
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Re: Great comments on new #namethetrait video

Post by Margaret Hayek »

DrSinger wrote: Tue Dec 05, 2017 6:13 am Re: Margaret,
[Margaret: OK, let me take another run at why I think this section is unhelpful, and let me do it this way. In the closest possible world in which NTT establishes anything about non-human animal moral value, it establishes not only that there is no moral value giving trait absent in all sentient non-human animals, but it establishes that all sentient non-human animals have moral value giving traits (e.g. by adding the relevant suppressed premises needed to make it valid). So it is pointless to consider some really far off possible world in it establishes only that there is no moral value giving trait absent in all sentient non-human animals without establishing that all sentient non-human animals have moral value giving traits (how would it even do that? By adding some weird premises that establish the former but not the latter? Why on earth would it ever do that?)]
It's relevant because if the issue is not fixed, the argument is still invalid even with the additional premise. Establishing

that there is no moral value giving trait absent in all sentient non-human animals

only means there is one animal with the moral value giving trait. That is why in the alternate version we have changed P2 from

(P2) ¬∃t ( T(t) ∧ ∀x ( A(x) ⇒ ¬P(x,t) ) ∧ ∀y ( ( CP(y) ∧ ¬P(y,t) ) ⇒ ¬ M(y) ) )

to

(P2) ∀x ( A(x) ⇒ ( ∃y ( CP(y) ∧ M(y) ∧ ∀t ( T(t) ⇒ ( P(x,t) ⇔ P(y,t) ) ) ) ) )

Without talking about the quantification issue, there is no explanation as to why we would have done this.

Also, regarding the article, I added in some stuff about essential properties, part 2 and changed the conclusion

Edit: Added a correction, do we think it is valid?
OK, so in your correction you have as your premise 3 (and I've changed SNAx to Ax for continuity with the prior sections):

(P3) ∀x (Ax ⇒ ¬∃t (Tt ∧ ( ¬Px,t ⇒ ( ∀y ( Hy ∧ ¬Py,t ) ⇒ ¬Ry ) ) ) )

If that in the relevant sense fixes the quantification issue you mention (and I'm sorry but I'm still not 100% clear on what that issues is supposed to be - e.g. why we have to interpret the argument as - in some possible world - first establishing that "there is no moral value giving trait absent in all sentient non-human animals" and then still failing to establish the conclusion), then why don't we just make that LF the original LF of P2? E.g. why not, in the first part of NTT, make P2:

(P2) ∀x (Ax ⇒ ¬∃t (Tt ∧ ( ¬Px,t ⇒ ( ∀y ( Hy ∧ ¬Py,t ) ⇒ ¬My ) ) ) )?

If your argument from your P1-P3 to your C in the correction is valid, then so would be this version of NTT with an analogous suppressed premises added in:

(P1) (C) ∀x ( Hx ⇒ Mx )
(P1.5) ∃t (Tt ∧ (∀x ( Hx ⇒ ( Mx ⇔ Px,t ) ) )
(P2) ∀x (Ax ⇒ ¬∃t (Tt ∧ ( ¬Px,t ⇒ ( ∀y ( Hy ∧ ¬Py,t ) ⇒ ¬My ) ) ) )
(P2.5) ∀t ( (∀x (Tt ∧ Hx ∧ Px,t ) ⇒ Mx ) ⇒ (∀x ( Tt ∧ Px,t ) ⇒ Mx ) )
Therefore (C) ∀x ( Ax ⇒ Mx )

But if that's right then there isn't an additional quantification issue with P2; the issue is just that suppressed premises P1.5 and P2.5 are left out.


Since you are just asking about the validity and not proving, I assume that you don't remember how to prove things in FOL? One of the many great things about the internet is that everything is online now! When I taught this I used truth trees / tableaux; for an overview see (https://en.wikipedia.org/wiki/Method_of_analytic_tableaux); for what I think is the actual text I used, in full and for free on line, see (http://tellerprimer.ucdavis.edu/pdf); you may want to see in particular chapter 7 of vol II (http://tellerprimer.ucdavis.edu/pdf/2ch7.pdf). Just let me know if you have any questions / need any help figuring it out...


I suspect that there may be some further issues about using the concept of exploitation - you might see a lot of bashing of that in the version of the wiki that you moved off of the main page.

I think that Brim would have a lot to say about that.

I'd recommend that for the first part of the argument you just stick to showing that non-human animals have some moral value, or, if you want to be precise, that they have enough as much moral value as intellectually and socially comparable humans (e.g. orphaned profoundly intellectually disabled humans about whom no one cares), or that they have enough moral value that it isn't OK for us to inflict enormous harm on them for relatively trivial benefits, or something like that.

In any event there's a need for a second part of the argument that establishes that this sort of moral concern for non-human animals requires veganism. You may recall all of that or see it in the original wiki that you moved off from the main page. What you're doing here in the correction so far is re-doing something like part 1 of NTT; part 2 is either going to require some empirical premises and / or need to make some more fine-grained comparisons to e.g. intellectually and socially comparable humans.

I actually think that you are in your correction doing what Isaac was doing - namely going by the vegan society definition of veganism which talks about exploitation. In that sense it's an analytic truth that if we should minimize harm / "exploitation" to non-human animals as far as practical & possible, then there's reason to be vegan, since minimizing harm / "exploitation" in this way is just what they mean by vegan. The only thing is that most of us mean eating a particular diet (no animal products / vegetarian + no dairy + no eggs), and it isn't always clear what minimizing as far as practical and possible means, or whether that would cover the diet in question. E.g. what if a carnist says "I just really like meat, so it just isn't possible, just isn't practical, for me to give that up; so I guess I'm a meat eating vegan!" That, presumably, is something you want to avoid, and to do it you need to connect the moral value issue to the diet / product purchasing issue in a clear way that doesn't leave "practical and possible" in the eye of the beholder - and that is likely going to involve empirical stuff (or at least leveraging certain comparisons to comparable humans; e.g. if the only way to get a given soft-drink that you really like (or even: to avoid great inconvenience; or even: to keep your current job; or even: to avoid costs to yourself that are even bigger than that, etc.) was to pay someone to torture & kill orphaned profoundly intellectually disabled humans to get it, this presumably would not be OK. Of course if you want to leverage those, then you're ruling out speciesism and going a bit more "full Monty" than if you just use something like a requirement to not inflict enormous harm on non-human animals for relatively trivial benefits and use empirical considerations to establish that this requires vegan diets in almost all circumstances, which is certainly doable and is compatible with some degree of speciesism and such).
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brimstoneSalad
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Re: Great comments on new #namethetrait video

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We might want to reference this one in the wiki:
http://philosophicalvegan.com/viewtopic.php?f=7&t=3660

And perhaps add it to the list of good arguments? The force of the argument is not as great, but the form is good and it avoids the implicit insult that Marginal cases carries. I think it has the same general idea of NameTheTrait, just done properly.
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Re: Great comments on new #namethetrait video

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(P1) (C) ∀x ( Hx ⇒ Mx )
(P1.5) ∃t (Tt ∧ (∀x ( Hx ⇒ ( Mx ⇔ Px,t ) ) )
(P2) ∀x (Ax ⇒ ¬∃t (Tt ∧ ( ¬Px,t ⇒ ( ∀y ( Hy ∧ ¬Py,t ) ⇒ ¬My ) ) ) )
(P2.5) ∀t ( (∀x (Tt ∧ Hx ∧ Px,t ) ⇒ Mx ) ⇒ (∀x ( Tt ∧ Px,t ) ⇒ Mx ) )
Therefore (C) ∀x ( Ax ⇒ Mx )
P1 has to be omitted, otherwise if P1 is true then ∀y ( Hy ∧ ¬Py,t ) ⇒ ¬My becomes false by default. I'm happy to change P2 to as it is there. In the correction it should remain just human in 1.5 and sentient non-human animal in P2.
I assume that you don't remember how to prove things in FOL?
I've never been taught how to, I don't know much about deduction. I've watched a few youtube videos and for propositional logic it doesn't look particularly difficult. I should be able to learn it, and prove the corrections validity. I'll let you know if I need help.
I actually think that you are in your correction doing what Isaac was doing - namely going by the vegan society definition of veganism which talks about exploitation. In that sense it's an analytic truth that if we should minimize harm / "exploitation" to non-human animals as far as practical & possible, then there's reason to be vegan, since minimizing harm / "exploitation" in this way is just what they mean by vegan. The only thing is that most of us mean eating a particular diet (no animal products / vegetarian + no dairy + no eggs), and it isn't always clear what minimizing as far as practical and possible means, or whether that would cover the diet in question.
I agree there's ambiguity as to what constitutes practical & possible, I was just correcting the validity, trying not to stray too far from how the argument was intended. We could just expand on R(x) to say what constitutes excluding exploitation as far as is possible and practicable.

Margaret can you check over this

http://philosophicalvegan.com/wiki/index.php/NameTheTrait#Part_1_Counterexample

I am not sure if I have done the instantiation thing correctly, it is something I saw nightcell do
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Re: Great comments on new #namethetrait video

Post by Margaret Hayek »

DrSinger wrote: Fri Dec 08, 2017 5:18 am Margaret can you check over this

http://philosophicalvegan.com/wiki/index.php/NameTheTrait#Part_1_Counterexample

I am not sure if I have done the instantiation thing correctly, it is something I saw nightcell do
Just quickly for now: the bit about instantiation seemed difficult to follow. One really nice thing about the truth tree method is that it BOTH (i) shows you that arguments are valid when they are (or that the premises + the negation of the conclusion is a logical contradiction), AND (ii) shows you how to give a counterexample when arguments are invalid (or when the premises + the negation of the conclusion is NOT a logical contradiction). If you can teach yourself how to use the truth tree method e.g. with the Teller chapters (and I think it shouldn't be too hard for you to do that) you should be able to confirm your counterexamples and see how to present them in a maximally clear way.

So I'd recommend learning the truth tree method of proving arguments valid / invalid, and running the LF of NTT through that.

I think that all you should really need to learn the truth tree method are the Teller chapters on

(1) fundamentals of truth trees for sentence / propositional logic (volume I chapter 8): http://tellerprimer.ucdavis.edu/pdf/1ch8.pdf/view, and
(2) fundamentals of truth trees for predicate / FO logic (volume II chapter 7): http://tellerprimer.ucdavis.edu/pdf/2ch7.pdf/view

Again, if you need any help, just let me know.
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Re: Great comments on new #namethetrait video

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I have a question regarding identity of indiscernibles as it relates to NTT:

Two objects. Object A and object B. Properties for object A include property x: having a given set of properties P at time T (for a human it would be things like human dna etc.). If one wishes to eliminate any and all differences between object A and object B then one would also have to eliminate property x. But this cannot be done. If one eliminates the property x then one can not claim to be talking about object A in the first place. Thus it is impossible to originally have two distinct objects whether hypothetical or not and to render them absolutely identical in terms of properties; their history as distinct objects prevent this from occurring. The historic property of having been A/property x at time T, is a property that B can never get, and vice versa.

Does this make sense?
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Re: Great comments on new #namethetrait video

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Turns out I can just throw the arguments in a FOL formula prover, in the form

(P1 ∧ P2 ∧ ... )⇒C

https://www.umsu.de/logik/trees/

What we get is

NTT - invalid, no surprises there since 'traits' have no bearing on anything in the argument, might as well be talking about toe nail size as far as the logical form is concerned.

\forallx(Hx\toMx)\land\forallx(Ax\to\neg\existst(Tt\land\negPxt\land(\forally(Cy\to(\negPyt\to\negMy)))))\to\forallx(Ax\toMx)

Correction - valid

\existst(Tt\land\forallx(Hx\to(Rx\leftrightarrowPxt)))\land\forallt(Tt\land(\forallx(Hx\to(Rx\leftrightarrowPxt))\to\forallx(Rx\leftrightarrowPxt)))\land\forallx(Ax\to\neg\existst(Tt\land\negPxt\land(\forally(Hy\to(\negPyt\to\negRy)))))\to\forallx(Ax\toRx)

Edit: Correction yields valid but it takes a while, pretty confident in it
Last edited by DrSinger on Sun Dec 10, 2017 6:10 pm, edited 2 times in total.
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Re: Great comments on new #namethetrait video

Post by Margaret Hayek »

Gregor Samsa wrote: Sat Dec 09, 2017 10:29 pm I have a question regarding identity of indiscernibles as it relates to NTT:

Two objects. Object A and object B. Properties for object A include property x: having a given set of properties P at time T (for a human it would be things like human dna etc.). If one wishes to eliminate any and all differences between object A and object B then one would also have to eliminate property x. But this cannot be done. If one eliminates the property x then one can not claim to be talking about object A in the first place. Thus it is impossible to originally have two distinct objects whether hypothetical or not and to render them absolutely identical in terms of properties; their history as distinct objects prevent this from occurring. The historic property of having been A/property x at time T, is a property that B can never get, and vice versa.

Does this make sense?
It's true that once you have an object it is impossible to change its historical traits so that it has the historical traits of another entity. But what P2 is really asking us to do on the alternative interpretation of NTT (that appeals to the identity of indiscernibles) is to consider an object, and imagine its present, future AND past traits HAVING BEEN different. It's saying that there are no traits absent in animals that, IF THEY HAD BEEN absent in us, would have rendered the entity that would have existed valueless.

What's confusing is that this entity would in no way have been us if it didn't have our essential properties, so P2 on the alternative interpretation isn't really comparing non-human animals to US with different traits at all - it's just comparing non-human animals to entities that have all the same traits of non-human animals - including absences of our essential traits and presences of non-human animals' essential traits. This seems to go against the original English presentation of NTT, which says "there are no traits absent in animals which if absent in humans would cause us to deem ourselves valueless," so the entities losing the traits were clearly supposed still to be us after losing them.

The big problem with the alternative version is that, because it is comparing non-human animals, not to us under some counterfactual situation, but to entities that have all of the exact same traits (including essential, historical ones) of non-human animals, which it asserts have moral value, it essentially begs the question. Anyone not inclined to accept the conclusion (that sentient non-human animals have moral value) will have no more inclination at all to accept P2 (that for each sentient non-human animal there is an entity that has all the same traits - which by the way is NOT us / a human - that has moral value), and it seems just as difficult to convince someone of the truth of P2 as to convince them of the truth of the conclusion directly.

For more on this see the NTT wiki sections on

http://philosophicalvegan.com/wiki/index.php/NameTheTrait#This_Alternative_Version_of_NTT_Begs_the_Question, and
http://philosophicalvegan.com/wiki/index.php/NameTheTrait#Excluding_Essential_Properties
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Re: Great comments on new #namethetrait video

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Margaret Hayek wrote: Sun Dec 10, 2017 2:19 pm
Gregor Samsa wrote: Sat Dec 09, 2017 10:29 pm I have a question regarding identity of indiscernibles as it relates to NTT:

Two objects. Object A and object B. Properties for object A include property x: having a given set of properties P at time T (for a human it would be things like human dna etc.). If one wishes to eliminate any and all differences between object A and object B then one would also have to eliminate property x. But this cannot be done. If one eliminates the property x then one can not claim to be talking about object A in the first place. Thus it is impossible to originally have two distinct objects whether hypothetical or not and to render them absolutely identical in terms of properties; their history as distinct objects prevent this from occurring. The historic property of having been A/property x at time T, is a property that B can never get, and vice versa.

Does this make sense?
It's true that once you have an object it is impossible to change its historical traits so that it has the historical traits of another entity. But what P2 is really asking us to do on the alternative interpretation of NTT (that appeals to the identity of indiscernibles) is to consider an object, and imagine its present, future AND past traits HAVING BEEN different. It's saying that there are no traits absent in animals that, IF THEY HAD BEEN absent in us, would have rendered the entity that would have existed valueless.

What's confusing is that this entity would in no way have been us if it didn't have our essential properties, so P2 on the alternative interpretation isn't really comparing non-human animals to US with different traits at all - it's just comparing non-human animals to entities that have all the same traits of non-human animals - including absences of our essential traits and presences of non-human animals' essential traits. This seems to go against the original English presentation of NTT, which says "there are no traits absent in animals which if absent in humans would cause us to deem ourselves valueless," so the entities losing the traits were clearly supposed still to be us after losing them.

The big problem with the alternative version is that, because it is comparing non-human animals, not to us under some counterfactual situation, but to entities that have all of the exact same traits (including essential, historical ones) of non-human animals, which it asserts have moral value, it essentially begs the question. Anyone not inclined to accept the conclusion (that sentient non-human animals have moral value) will have no more inclination at all to accept P2 (that for each sentient non-human animal there is an entity that has all the same traits - which by the way is NOT us / a human - that has moral value), and it seems just as difficult to convince someone of the truth of P2 as to convince them of the truth of the conclusion directly.

For more on this see the NTT wiki sections on

http://philosophicalvegan.com/wiki/index.php/NameTheTrait#This_Alternative_Version_of_NTT_Begs_the_Question, and
http://philosophicalvegan.com/wiki/index.php/NameTheTrait#Excluding_Essential_Properties
Thank you.
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