/lit/ - Literature

[Anonymous No.15639234]

How the FUCK do we break the is-ought divide

[Anonymous No.15639250]

>>15639234
But "What Ought To Be" IS "That's just your opinion." To say otherwise is massive cope.

[Anonymous No.15639279]

>>15639234
is-ought divide itself break the divide, it's self-refuting.

[Anonymous No.15639294]

>>15639234
Either elevate "your opinion" to the level of "what is" and "what ought to be", or reduce "what is" and "what ought to be" to the level of "your opinion."

[Anonymous No.15639308]

>>15639234
Literally with might.

[Anonymous No.15639320]

>>15639279
Elaborate

[Anonymous No.15639337]

>>15639294
I could take the high road
But I know that I'm going low
I'm a ban, I'm a bandito
In city, I feel my spirit is contained
Like neon inside the glass, they form my brain
But I recently discovered
It's a heatless fire
Like nicknames they give themselves to uninspire
Begin with bullet, now add fire to the proof
But I'm still not sure if fear's a rival or close relative to truth
Either way it helps to hear these words bounce off of you
The softest echo could be enough for me to make it through

[Anonymous No.15639341]

>>15639234
Divine revelation.

[Anonymous No.15639354]

>>15639234
ought is also opinion

[Anonymous No.15639373]

It can't be defeated. The Is-Ought and Fact-Value distinctions show that morality and values are subjective to the individual. It's in the individual in which value and judgement is born.

[Anonymous No.15639382]

>>15639234
Kant broke it. What x ought to do is what they should do.

[Anonymous No.15639398]

>>15639234
By violence against those who´s opinion it isn´t, until it becomes their opinion as well.

[Anonymous No.15639404]

>>15639234
The is-ought distinction has nothing to do with "opinion", pleb.

[Anonymous No.15639411]

>>15639404
"That's just your opinion."

[Anonymous No.15639420]

>>15639373
Lol, no.

[Anonymous No.15639421]

>>15639320
are you saying I ought to elaborate because my point was not understood? that's is from ought statement, I'm afraid you can't ask that , retard.

[Anonymous No.15639422]

>>15639404
Yes it does it's positive vs normative and how to bridge

[Anonymous No.15639428]

>>15639422
Are you retarded?

[Anonymous No.15639440]

>>15639421
There was no aught implied retard. Maybe if he said you should elaborate that would be one thing, but he didnt express it that way.

[Anonymous No.15639451]

>>15639440
elaborate is just shorter for should elaborate, I'm afraid it's too let, he's burn in hell.

[Anonymous No.15639457]

>>15639451
late*

[Anonymous No.15639458]

>>15639234
Let me do my good deed for the day and explain

+ Normative statements are those that LOGICALLY ENTAIL statements of the form "It ought to be the case that P"

+Factual states DO NOT LOGICALLY ENTAIL statements of the form "It ought to be the case that P"

That's it. Nothing about "opinion" or "subjectivity" or whatever you just pulled out your ass.

[Anonymous No.15639463]

>>15639373
>he hasn't read Hillary Putnam

To make an Is statement is to acknowledge an epistemic criteria which suggests the Is. The the chair IS red. But why do I think that? Well, I'm viewing what I believe is a chair and I believe it's colored what culturally is defined as red. Other people agree that it's red. But Ought I believe the chair is red? Should I believe the chair is red?
There is no distinction between facts and values or Is and Ought. To make an Is statement or a Fact statement implies there are things we OUGHT believe are Facts. The only way out is to not make any statements about anything at all, which to me is a reductio ad absurdum to the arguement. We make statements about things all the time and we are correct. We make predictions all the time and we are correct. The difficulty of parsing what epistemic thresholds we need to meet to "believe" in anything doesn't mean it's impossible.

[Anonymous No.15639468]

Fink it fru luv :^)

[Anonymous No.15639471]

>>15639421
>are you saying I ought to elaborate
No retard

[Anonymous No.15639479]

Is this the issue concerning the conflation of is/ought / descriptive/prescriptive statements?
I feel like there are five different is/ought divides being talked about.

[Anonymous No.15639480]

>>15639458
Where does Normative Statements logically entail their conclusions from? From their fundamental axioms and values? These values aren't deduced from reality but is subjective for each person and a result of their particular psychology, culture, or genetics

[Anonymous No.15639495]

>>15639463
You're conflating semantics/metaphysics with epistemology/pragmatics. Is-Ought is a distinction that applies in virtue of logical form.

[Anonymous No.15639513]

>>15639234
Through divine revelation.

[Anonymous No.15639516]

>>15639480
Nope, modus ponens applies to propositions in every culture.

[Anonymous No.15639524]

>>15639457
False, learn diction. That is a pssible interpretation, but In english it is more commonly interpreted in the imparitive mood. You are the one assuming the form if intent behind the statement. And i highly doubt he meant you should answer him as a moral duty.

[Anonymous No.15639531]

>>15639234
Appeal to nature like Greek Sophists and everyone else in history and don’t give a shit what that fatty said

physis versus nomos

[Anonymous No.15639559]

By dilemma:

Let "I" represent an arbitrary "is" statement and "O" an arbitrary "ought" statement, and assume that every statement is either an "is" statement or an "ought" statement.

Then the statement "either I is true or O is true" must either be an "is" statement or an "ought" statement.

If it's an "is" statement then we can derive an is from an ought, as the "is" statement that "either I is true or O is true" together with the "is" statement that "I is not true" jointly entail the ought statement that "O is true”.

If it's an "ought" statement then again we can derive an is from an ought, as the "ought" statement that "either I is true or O is true" is entailed by the "is" statement that "I is true".

So whether "either I is true or O is true" is an "is" statement or an "ought" statement--and it has to be one or the other--we can derive an ought from an is.

[Anonymous No.15639560]

>>15639531
Why not simply kill yourself?

[Anonymous No.15639574]

>>15639516
Yes and where do these propositions come from? I'm not arguing against the logic, I'm arguing that the propositions are entirely subjective

[Anonymous No.15639608]

>>15639234
Who gave the best critiques of Hume, /lit/?

[Anonymous No.15639733]

"Pure" oughts are just meaningless. You can say something like if I want to not die of thirst, then I ought to drink water, but asking whether you "ought" to drink water devoid of any other context just doesn't mean anything, it's like asking what colour the letter L is.

[Anonymous No.15639813]

>>15639495
You're an idiot. Nothing I said involves Metaphysics and "pragmatics" isn't a field of Philosophy it's just something normies say because their brains hurt to think too deeply
Everything I wrote can be put into a logical statement
"The chair is red if the chair is red."
P > P
What makes the chair red? Consensus and Observation
(C & O) > P
Epistemology is intimately entwined with Logic, I'm not sneakily or recklessly conflating them. In order to know if a logical statement is correct you have to break it into the smallest parts and assess them for truth values. If you can't do that, no logical statement can be proven true or false.

[Anonymous No.15639850]

>>15639471
it's self-refuting because it's called a problem, a law guillotine, which implies that you should not derive ought from is because it's incoherent.

[Anonymous No.15639867]

>>15639234

[Anonymous No.15639880]

>>15639867

[Anonymous No.15639898]

>>15639733
"Pure" oughts are obviously meaningful, even when not implicitly relativised to context.

Regardless of context, it is true that I ought do the right thing. And that I ought not torture babies for fun. And, if consequentialists are right, that I ought not act in such a way as to bring about anything less than the best possible outcome. And, if deontologists are right, that I ought not act in such a way as to break a moral rule. And, trivially, that I ought to what I ought do.

The fact that all these claims at the very least admit of being true or false guarantees that they're not meaningless, as you claim they are.

[Anonymous No.15639960]

what is —— what will be

[Anonymous No.15639978]

>>15639898
Your examples all have defined goals though. They're things you ought to do if you want to increase wellbeing, decrease suffering, follow certain moral laws, or whatever.

If there's no goal or state of affairs you are trying to bring about, then it doesn't mean anything to ask what you ought to do.

[Anonymous No.15639999]

>>15639978
No. Even if your goal is to do evil you ought do good.

[Anonymous No.15640157]

>>15639999
guess I'll have to take your word for it

[Anonymous No.15640322]

>>15640157
I don't see why. Almost any plausible account of moral action will have it that what you ought do, morally speaking, is largely divorced from your goals.

According to the deontologist, for instance, you ought act in such a way as to break moral rules regardless of what your goals are.

And for a more concrete example, note how plausible and--to your point about meaninglessness--*intelligible* the following claim is: regardless of what your goals are, even if none of your goals involve living a moral life, you ought not, morally speaking, torture babies for fun.

[Anonymous No.15640337]

>>15639608
bumpan for interest

[Anonymous No.15640375]

Be powerful. Overcome yourself, then overcome the world.

[Anonymous No.15640502]

>>15639608
Arthur Prior came up with this structural counterexample to Hume's thesis that you can't derive an ought from an is >>15639559

[Anonymous No.15640519]

>>15640502
That's retarded. The claim is they're both the same thing. Not that facts don't exist or oughts don't exist

[Anonymous No.15640548]

>>15639279
cringe and wrong.
Tip: if he just makes a hot take, he is wrong in 99% of the cases
>>15639234
you can't, that's the point

[Anonymous No.15640560]

Copypasted from another thread:
Kant gives an interesting answer in the first chapter of the Critique of Practical Reason (give it a read, it's only 30 pages long).
His argument hinges on the claim that there is no choice when the will is only determined by external, empirical causes and motives. When we are determined in such a way we don't chose, rather we act as machines (empirical effects mechanically influence our actions). He also claims that through the categorical imperative ( a formal practical principle) we can determine our will through our own pure practical reason, which gives us maxims that are not derived from the aforementioned contingent empirical factors (like my sensory perceptions, my arbitrary preference based on my subjective feeling of pleasure and displeasure, and so on): only in this case we can talk about choice (if any part of this poor summary of mine seems dubious to you, check that first chapter: there Kant argues each one of these points in greater detail).

So the answer to the question "why should I follow the CI?" is: we can talk about "choice" when we follow the CI, there is no such thing as "choosing not to follow the CI" (when you don't follow it you're acting as an irrational automaton/beast/however you want to call it, which is incapable of choice and deliberation). Rather than saying that someone "chose not to follow the CI" we should say that someone "failed to follow the CI".

[Anonymous No.15640578]

>>15640502
Also it can inclusive or in which they both can be true.
He hasn't explained why it's exclusive or why it must be set up between those

[Anonymous No.15640597]

>>15640502
This is just a logic fail. In the first case how do you derive "either I is true or O is true" if "I is not true"?
If "I is true" then disjunctive introduction gives you "either I is true or O is true" like in the second case but "I is not true" prevents that. For example the moon is made of green cheese or Trump is a tranny. The moon is not made of green cheese so Trump is a tranny. Not a valid deduction since the starting disjunction is not justified.

[Anonymous No.15640648]

>>15640322
>And for a more concrete example, note how plausible and--to your point about meaninglessness--*intelligible* the following claim is: regardless of what your goals are, even if none of your goals involve living a moral life, you ought not, morally speaking, torture babies for fun.
That's just a nonsense statement to me. I ought not to torture babies if my goal is to minimise suffering, or to adhere to some external code of moral laws, but there isn't any unqualified "ought" just floating around unattached to anything.

But we're just going round in circles, so i don't know what more can be said.

[Anonymous No.15640670]

>>15640578
Yeah this is another thing wrong with it
>So whether "either I is true or O is true" is an "is" statement or an "ought" statement--and it has to be one or the other
Why does it have to be one or the other? If we have is and oughts why not witty statements or based ones?

[Anonymous No.15640683]

>>15639850
>which implies that you should not derive ought from is because it's incoherent.
No it doesn’t retard

[Anonymous No.15640696]

>>15640670
Terrible ontology and, if prior meant exclusive or, ok logic. It would be valid assuming we didn't know the truth statement and it must be either or but yeah it's retarded

[Anonymous No.15640709]

>>15640670
Well either you're right or I'm right. Assuming it's you then im wrong. If im wrong then prior is correct and since you're right prior is wrong. Through transitivity we can now set up an algebraic ring and develop a new math to shock the world with or I'm sure hume thought so

[Anonymous No.15640714]

>>15639559
>and assume that every statement is either an "is" statement or an "ought" statement.
Obviously false premise

[Anonymous No.15640757]

>>15640683
sorry, it doesn't imply, it literally is in the definition of law and problem.
what's incoherent is also just based on fee fee when it really comes down to, empiricism is retarded.

[Anonymous No.15640782]

>>15639382
What is the difference between ought and should?

[Anonymous No.15640793]

>>15640782
In this sense should just means it is. Or it's the 'is' of ought. There's only one thing you can do that that's what you think you should do, not necessarily in a cognitive sense but precognitive if they're a psychopath

[Anonymous No.15640910]

>>15640597
>In the first case how do you derive "either I is true or O is true" if "I is not true"?
You don't. The first horn of the dilemma relies on the inference rule of disjunctive syllogism--it's the second horn that uses disjunction introduction. Read through it again and you'll see what I mean.

>Not a valid deduction since the starting disjunction is not justified.
This is not what "valid" means. Validity is a purely formal property of arguments: it doesn't matter whether the premises are true or justified or whatever. All that matters is whether the conclusion follows logically from the premises.

Remember, I'm just trying to show that you can validly derive an ought from an is, so I don't need to show that any of the "ought" or "is" statements I'm dealing with are true or justified, just that the former will sometimes follow logically from the latter.

In your Trump example, for instance, you have indeed presented a valid deduction. So if your goal, like mine, was just to establish that a certain kind of deduction is valid, you've succeeded. Of course you haven't succeeded in establishing the *conclusion* of your deduction. But this is irrelevant, as establishing the disjunction involved in my deduction was not my goal.

[Anonymous No.15640914]

>>15640714
Then it should be easy for you to provide a counterexample.

[Anonymous No.15640920]

>>15640578
The "or" is intended to be read as inclusive. This does nothing to invalidate the inference. Check it again.

[Anonymous No.15640926]

>>15640910
Assuming A or B
Not A
Therefore B
Is not a valid argument. If it was you could prove literally anything this is the principle of explosion. Take a basic logic class kiddo you're wrong

[Anonymous No.15640958]

>>15640920
But why are there only is and ought statements? Why does a statement have to be one or the other?

[Anonymous No.15640975]

>>15640648
Imagine you lack the goal of minimizing suffering and begin torturing babies. Are you really saying that if I, who knows about your goals, came upon you and said "you really shouldn't be doing that--it's immoral", you'd throw up your hands and say "you're talking gibberish--I have no idea what you mean!"

This just comes across as disingenuous. Obviously such talk is meaningful, and intelligible to any competent speaker of English.

[Anonymous No.15640979]

>>15639559
The only thing you show here is that an argument being purely logically valid - and nothing else - does not make the argument as a whole valid. This has no baring on the debate because its only an arbitrary logical deduction, and logical validity is useless by itself.

[Anonymous No.15640982]

>>15640979
It's not even logical he's made several mistakes. See >>15640597 and >>15640670

[Anonymous No.15640988]

>>15640670
lol wat? The fact that the is-ought distinction partitions the space of propositions doesn't mean that statements can't have other properties.

Compare: every statement is either true or not true. But clearly this doesn't mean statements can't also be witty.

[Anonymous No.15640989]

>>15640920
Why is it inclusive then? And how do you go from they both are correct so only one is. And wth is trying to suggest oughts and is's exist exclusive of each other

[Anonymous No.15640992]

>>15640782
For most purposes, and for the purposes of this discussion, there is no important difference.

The other anon's response to your question is literal nonsense.

[Anonymous No.15640994]

Piggybacking maestros. I understand tree and a little fitch style natural deduction but I'm studying gentzen and I've got the basic idea in overview but not in particular
Help, there's nothing on yt besides a few questions being done without explanation

[Anonymous No.15640997]

>>15639421
But I did ask that, so you saying I can't ask that is incorrect.

[Anonymous No.15641000]

>>15640988
You haven't shown that it partitions the space of propositions. Why must every statement have a truth value or an ought value?

[Anonymous No.15641002]

Political philosophy is easy.

1. define mutually agreed principles
2. identify a specific issue
3. apply mutually agreed principles to the issue to identify a desired outcome
4. consult with technocrats about the best way to proceed from the origin to the outcome
5. confirm that the means are not contrary to the principles
6. proceed

>"but what if principles cannot be mutually agreed?"
Then you call in the military.

[Anonymous No.15641005]

'Is' is derived from Ought.
Objects and isnesses don't just float around in space independently of consciousness. Objectness is a presentation, or projection, of mind. The atoms overthere don't think they're more together with the atoms we call that book than the air molecules around it. Pick a random atom and, objectively, it makes an object with every other atom everywhere as much as any other thing we call real. Or rather no objects are independently real from our evolved perception of particles. We recognize patterns because they matter to us, we have an Ought to see the Book as a thing rather than the air molecule abd every third page of the no-longer a book.
Ought>Is. Just like Word doesn't mean Word objectively, every 'thing' is Intersubjective presentation.
If I studied philosophy this would be the foundation to my PhD, but I am not, so fuck you.

[Anonymous No.15641006]

>>15640926
Disjunctive syllogism *implies* explosion. Both principles are valid in classical logic. Neither principle allows you to prove everything UNLESS you assume a contradiction to be true. And since contradictions clearly can't be true, this isn't a problem.

[Anonymous No.15641008]

>>15640958
It's just a plausible generalization. I'm open to considering counterexamples if you think you have any.

[Anonymous No.15641011]

>>15641005
It's okay Berkeley did it for you

[Anonymous No.15641012]

>>15640979
What? The debate is over whether you can validly derive an ought from an is. The result you're talking about thus cuts to the very core of the debate.

[Anonymous No.15641022]

>>15640997
b-but you can't just get ought from is

[Anonymous No.15641024]

>>15641011
No, Plotinus through Plato did.

[Anonymous No.15641028]

>>15641000
I agree that I haven't shown this. Nonetheless, it's a plausible generalisation. Every argument has to take something for granted--that's what premises are. But, again, I'm open to hearing any counterexamples.

[Anonymous No.15641029]

>>15641006
I gave the derivation you used:
Assuming A or B
Not A
Therefore B
You can clearly insert any not A that is true and B can be anything. That proves everything. Assuming A or B is an invalid step in that derivation.

Here is an example:
Assume (1>2) or any theorem you want to prove in math
Not (1>2)
Therefore any theorem you want to prove
You are painfully wrong and if you went to the board and used this is any proof class you would be embarrassed

[Anonymous No.15641050]

>>15641029
I don't see what the problem is supposed to be. Your example is indeed an example of a valid argument. But of course not every valid argument will be *convincing*, even if its premises are true.

For instance, the argument "P therefore P" is valid if any argument is. But it's not going to convince anyone that P is true!

[Anonymous No.15641067]

>>15641050
I mean that's true for every arguments.
The degree of faith is subjective, a Solipsist just doubts more than a fraud skeptic like Matt dillychips. There's no objective basis for Reason. The obvious is not logically obvious.

[Anonymous No.15641071]

>>15641022
Too bad fag lol

[Anonymous No.15641075]

>>15640982
There are no mistakes. Those anons are very confused.

If you're interested, the argument is due to one of the most important logicians of the second half of the 20th century: Arthur Prior. Prior was the inventor of tense logic. He first made the argument in the paper ""The autonomy of ethics".

[Anonymous No.15641078]

>>15641050
Alright you clearly don't have any training in formal logic so I'm going to again point to the effect of your argument in that it literally proves everything. Shit it also proves the negation of everything. Assuming the validity of an arbitrary disjunction is not a valid logical step if you're going to do that you may as well assume what you're trying to prove

[Anonymous No.15641084]

>>15641075
I clearly pointed out the mistake
>>15640926
>>15641029
If he made the argument as presented he is a retard

[Anonymous No.15641102]

>>15640989
An inclusive "or" doesn't mean that both disjuncts *are* true if the whole disjunction is, just that both *can* be true consistent with the truth of the whole disjunction.

>And wth is trying to suggest oughts and is's exist exclusive of each other
Not sure what you mean. However, people have definitely been suggesting that you can't validly derive an ought from an is. This is what Hume thought, for instance, and it's what I've been trying to refute.

[Anonymous No.15641108]

>>15641078
lol so I guess you don't think P entails P either then, cos tHAt WoUlD pROve EVeRyThINg

[Anonymous No.15641112]

"Please bring me glass of wine"
Can this sentence be true or false? How about this one:
"Hey joe!"
Obviously they can't be true or false. Ought statements are the same way. Saying "everyone ought to do good" is like saying "congratulations, you did good!". It is not like saying "This act is good."

Ought statements are not truth-apt. They are not true or false.

[Anonymous No.15641126]

>>15641084
The inferences you are calling "mistakes" are valid in classical logic. Look up "disjunctive syllogism" or "ex falso quodlibet" and read a bit about them if you're unsure.

[Anonymous No.15641134]

>>15641112
This view runs into the Frege-Geach problem.

[Anonymous No.15641148]

>>15641108
And this is how I can tell for sure that you've never taken a formal logic class
(A Or Not A) Law of Excluded Middle
(If A Then A) Material Implication
If A Then A is the same as A entails A. So yes you definitely can get A entails A for an arbitrary A.

[Anonymous No.15641150]

>>15641084
He states the argument more or less as I did in my first post.

If you're posting on /lit that you think an accomplished professional mathematician made elementary logical errors in his published work, maybe think twice.

[Anonymous No.15641153]

>>15640975
>Imagine you lack the goal of minimizing suffering and begin torturing babies. Are you really saying that if I, who knows about your goals, came upon you and said "you really shouldn't be doing that--it's immoral", you'd throw up your hands and say "you're talking gibberish--I have no idea what you mean!"
Impossible to say really, since I can't really remove myself from my own consciousness in which I do have that goal. Of course in the context of sane-minded individuals who have been culturally conditioned by the society they've grown up in, questions about what is moral or "should be done" make sense because there are implicit goals assumed in the communication. What is good or ought to be just means what adheres to a socially agreed upon goal like upholding God's law or minimizing suffering, etc.

If I was some kind of psycopath who had been raised by wolves or something and had no concept of an agreed-upon morality, I might well find such a statement to be gibberish.

[Anonymous No.15641158]

>>15641126
No they are not valid in classical logic. Assuming an arbitrary disjunction is not logically valid. Point me at the rule of logic that allows that.

[Anonymous No.15641160]

>>15641148
What about this argument?

A
If A then B
---------
B

[Anonymous No.15641165]

>>15641150
>He states the argument more or less as I did in my first post.
Since you don't even understand basic formal logic I'm going to guess less. I can't find a link to the paper that isn't paywalled

[Anonymous No.15641177]

>>15641158
Assumptions a never logically valid or invalid. The validity predicate only applies to arguments. You keep making this error. I wonder why?

In any case, my claim was that disjunctive syllogism and explosion are both classically valid. My initial argument relied only on the former of these and on disjunction introduction.

And remember, my argument wasn't using disjunctive syllogism to establish the conclusion *of the syllogism*. The argument just illustrates that if disjunctive syllogism and disjunction introduction are both valid, then you can validly derive an ought from an is.

[Anonymous No.15641180]

>>15641160
If A and (If A the B) are true then that is certainly a valid argument it's just Modus Ponens. But you can't just assume that either of them are true.

[Anonymous No.15641191]

>>15641165
You can find Prior's argument in exactly the form I stated it on the first page of JC Beall's (another logician) paper "A neglected reply to Prior’s dilemma". This one's open access.

[Anonymous No.15641206]

>>15641180
Ok good. This is progress. My rendition of Prior's argument was as two instances of conditional proof followed by a constructive dilemma. So while I initially made the assumptions you are criticizing, all the assumptions were discharged by the end of the argument.

[Anonymous No.15641223]

>>15641177
>Assumptions a never logically valid or invalid
This is retard tier. You used disjunctive syllogism on a disjunction you assumed to be true. That is invalid. You're wrong no one with any formal training will say that you're right
>And remember, my argument wasn't using disjunctive syllogism to establish the conclusion *of the syllogism*
Again you show how out of your depth you are with this. These aren't syllogisms. Disjunctive syllogism is called that in propositional logic by analogy

[Anonymous No.15641249]

>>15641102
To say ought comes from is you need predicate logic

[Anonymous No.15641254]

>>15641206
But your conditional proof had two conditions The condition you wanted:
"either I is true or O is true" is either an is or an ought
The condition you didn't want and didn't even realize you were introducing
"either I is true or O is true" is a true statement
You think you discharged the first condition but left the other one hanging.

[Anonymous No.15641264]

>>15641223
Could you tell me what definition of "valid" you have in mind?

The standard definition has it that an argument is valid just in case any uniform substitution for nonlogical constants that makes all the premises true also makes the conclusion true.

All the inferences I made were valid on this definition.

[Anonymous No.15641299]

>>15641254
That's not how the conditional proof went. *One* of the assumptions for *one* of the *two* conditional proofs is the second assumption you mentioned. This assumption was discharged one the relevant conditional was established. The other assumption you mentioned was used in the constructive dilemma, not in either of the conditional proofs.

It's probably easier to just look at the Beall paper since he has formatting advantages I lack here.

[Anonymous No.15641309]

>>15641249
No, you need a logic with deontic operators. That logic can be propositional (i.e. it can lack quantifiers).

[Anonymous No.15641341]

>>15641299
But you didn't establish the relevant conditional. You think that you've derived an ought from "either I is true or O is true" if it is a true statement but what if it's not a true statement?

[Anonymous No.15641384]

>>15641341
That's the beauty of conditional proof: you don't need the assumptions you discharge to be true!

You start with a set of assumptions, S, and temporarily assume the members of S are all true. From this assumption you then derive some intermediate conclusion, C. Then, by conditional proof, you infer that IF S then C. It's at this point that your original assumption that all the members of S are true is discharged, so it actually has no bearing on the conditional you've derived whether the members of S are true or false!

[Anonymous No.15641414]

>>15641341
Isn't his premise:
>for each statement S, S is either I or O
in other words,
>not I -> O
>not O -> I

[Anonymous No.15641433]

>>15641384
Yes and if the rest of your derivation was correct you would conclude that:
If "either I is true or O is true" is a true statement,
then we can derive an ought from an is.
But that is not what you claim instead you say:
we can derive an ought from an is.
By your own explanation you should be giving a conditional. You are extremely confused

[Anonymous No.15641443]

>>15641414
No because in "either I is true or O is true" I and O are arbitrary. You can't just pull the disjunction A or B for arbitrary values out of thin air

[Anonymous No.15641460]

>>15641309
If you're saying anything comes from another you need a predicate of it. To say ought comes from is you say Io. In prop logic you can only make the claim o comes from i. You can't examine it

[Anonymous No.15641513]

>>15641433
The conditional proof is meant to establish that if "either I is true or O is true" and "I is not true" then "O is true". Because of the nature of conditional proof, I was able to establish this conditional using only assumptions that were eventually discharged.

Crucially, this is NOT the conditional you've just claimed I was trying to establish. My conditional says nothing about deriving an ought from an is. Rather, it is an *example* of a derivation of an ought from an is.

Or, rather, it *might* be an example of this. What we do know is that either this conditional *or* the other conditional I establish(again, using only discharged assumptions) is an instance of an ought being derived from an is.

So either way, an ought has been derived from an is.

Really you should just look at the first page of Beall's free-to-access paper, which lays this all out very clearly. Or at least re-read my initial argument. You're continued claims that "no, it's the professional mathematicians who are wrong!" are getting a little embarrassing, especially when peppered with so many ironically misplaced insults.

[Anonymous No.15641530]

>>15641513
Can you briefly help me w gentzen style natural deduction?

[Anonymous No.15641531]

>>15641460
I'm not saying anything about "coming from". I'm talking about valid deducibility. And you can definitely make claims about valid deducibility in the metalanguage of propositional logic.

But, again, you need deontic operators to make the claims we're interested in here. These, however, are *sentential operators*, not predicates of names.

[Anonymous No.15641575]

>>15641513
>You're continued claims that "no, it's the professional mathematicians who are wrong!
The very paper by Beall that you're talking about is on how Prior's dilemma is wrong you retard.

And again the result of your first conditional is
If "either I is true or O is true" is a true statement,
then we can derive an ought from an is.
WTF happens if "either I is true or O is true" is not true?

[Anonymous No.15641603]

>>15641531
It can be valid but trivially so.

I don't think it matters what ought or is would be. What's important is that making a claim that they both differ and then justifying this by assuming they differ (through a disjunction) is hardly proof. You can claim any two things contradict the other semantically. You can't actually explore ought vs is in any meaningful manner in logic. I think if you were trying to justify one predicapting the other then you can't meaningfully examine it (outside of referential problems) in proposition logic

[Anonymous No.15641608]

>>15641513
Fucking moron see my own fucking argument spit at you by a credentialed source

https://www.barrymaguire.com/uploads/2/3/2/7/23270406/barry_maguire_grounding_the_autonomy_of_ethics_offprint.pdf

Charles Pigden (1989, 2010) has argued that we get a problem with explosion and disjunctive syllogism because in such cases the ethical expressions in the conclusions are contingently vacuous.6 (This is easiest to see with premise 1 in the Prior argument as presented above.) Pigden then defines an alternative principle, namely non-vacuous logical auton-omy: no non-ethical propositions entail a non-vacuous ethical proposition.7M in premise 1 of Prior’s argument occurs vacuously, since R entails the dis-junction of R and any proposition you like. Assuming R is true, the disjunc-tion will be true. Similarly with explosion. (R & ~R) entails any proposition whatsoever. Hence neither constitutes a counterexample to non-vacuous logical autonomy

GTFO of here

[Anonymous No.15641620]

>>15641608
Page 192

Charles Pidgen
PhD La Trobe (1985)
MA Cambridge (1983)

[Anonymous No.15641628]

>>15641620
Where is you God now?

[Anonymous No.15641631]

>>15639234
Be a based virtue ethicists

[Anonymous No.15641664]

>>15639234
By helping me w my hw

[Anonymous No.15641714]

>>15641513
is this guy gonna come back to face the music and admit he was wrong LMAO

[Anonymous No.15641724]

>>15641714
I think they spoke past each other that guy was saying the logical form is okay and any ought is can be proven not necessarily the ought or is.

[Anonymous No.15641742]

>>15641714
My gf's getting us popcorn

[Anonymous No.15641749]

>>15641742
Don't mind her she's stupid

[Anonymous No.15641772]

>>15639813
Cringe. You've never taken a logic class in your life.

[Anonymous No.15641829]

>>15639559
>If it's an "is" statement then we can derive an is from an ought, as the "is" statement that "either I is true or O is true" together with the "is" statement that "I is not true" jointly entail the ought statement that "O is true”.

Incorrect. Let's label the various statements thus:

a) (I or O)
b) Not I
c) (I or O) and (Not I)
d) O

It is correct that (c) logically entails (d). Since O is an ought-statement, that would require that (c) not be an Is-statement. Which it is not. Statement (a) and statement (b) are both Is-statements, but the conjunction of (a) and (b) -- aka, statement (c) -- is not an Is-statement since it is logically equivalent to O, which again is an Ought-statement.

[Anonymous No.15643169]

>>15639234
There is no gap. Is and Ought are the same. Any ought can be converted into a "is" statement by rephrasing. IE: "Is preferable that..."

[Anonymous No.15643218]

>>15643169
That is also a normative statement, my dude. If it logically entails an ought-statement, then it's normative.

[Anonymous No.15643605]

>>15639234
Might is right.

[Anonymous No.15643639]

>>15641608
>https://www.barrymaguire.com/uploads/2/3/2/7/23270406/barry_maguire_grounding_the_autonomy_of_ethics_offprint.pdf

Are you serious? Pigden *accepts* Prior's argument. What he points out is that the argument works for any "ought" statement O. He then conjectures that it's impossible to derive an ought from an is using an argument that only works for *some* ought statements, and points out that Prior's argument doesn't refute *this* impossibility claim. I agree, but this does nothing to diminish the fact that Hume's original claim was refuted by Prior.

[Anonymous No.15643650]

>>15641829
There's a lot wrong with this. First of all you don't need c) as an intermediate step in order to infer d) from a) and b). The rule of disjunctive syllogism takes two propositions of the form of a) and b) as input and spits out a proposition of the form of d).

While your inference from c) to d) is valid, is not the inference I appealed to. In fact I'm not sure your inference has a commonly accepted name, as people tend to just use disjunctive syllogism instead.

The other problem is that it is not enough for c) and d) to be logically equivalent that c) entail d)--d) also has to entail c). And it clearly doesn't. While d) entails the first conjunct of c)--(I or O)--it doesn't entail the second conjunct--(not-I).

So there's no issue with my argument here.

[Anonymous No.15643656]

>>15639234
"Ought" is a purely human construct with nothing tying it to material reality. It's an arrogant lie we tell ourselves as if what will be isn't due to a confluence of factors completely beyond our control. What "was" is immutable. Because it already happened, it is the only thing that could have happened. The future is a series of events which are the only things that can happen, because it is the cascade of events which will become the only things that could have happened. "Ought" has nothing to do with it.

[Anonymous No.15643657]

>>15641724
I think this is basically right, though I would have put it differently. My argument shows that you can sometimes derive an ought from an is. What it does not do--and does not even *purport* to do--is derive any "ought" statement from reasonable assumptions.

[Anonymous No.15643659]

>>15639234
Through growing up, you silly ballsack

[Anonymous No.15643670]

>>15641575
Beall explores a response to Prior's dilemma. What he does not do is explore the incoherent confused nonresponse you're proffering while persistently making elementary mistakes in reasoning.

Again, the conditional proof is meant to establish that if "either I is true or O is true" and "I is not true" then "O is true". Your insistence to the contrary is cute as an attempt to save face, but embarrassing given that you claim to have looked at Beall's paper. Beall states the argument exactly as I have, and disagrees with you that it requires establishing the conditional you're so obsessed with.

I do hope you're a teenager who's only read about logic on the internet or something, otherwise your university education has completely failed you. If so, maybe you'll get into a top college some day soon and end up in my classroom, where we can probably have a much more cordial and productive discussion and I can educate you on your mistakes in person.

[Anonymous No.15643671]

>>15641180
Sound =//= Valid

[Anonymous No.15643694]

>>15643671
Tell that to this guy
>>15640597
>Not a valid deduction since the starting disjunction is not justified
lmao

[Anonymous No.15643728]

>>15640597
Hey buddy. Another anon asked me to illuminate on the distinction between sound and valid.
A valid argument is an argument where the conclusion follows from the premises. The premises could all be wrong while the argument would still be valid.
Example:
A dragon lives nearby my house.
Wherever a dragon lives, there is a cave full of gold.
Conclusion: There is a cave full of gold near my house.
Bothe premises are false, but the conclusion follow from the premises.
In a sound argument, the conclusion follows from the premises and the premises are true.
Example:
Anon is browsing /lit/.
If anon is browsing /lit/, then anon uses the website 4channel.org.
Conclusion: Anon is using the website 4channel.org.
Both premises are true and the conclusion follows from the premises, meaning that the argument is sound.
Summary
In a valid argument the conclusion follows from the premises.
In a sound argument the conclusion follows from the premises and all premises are true.

[Anonymous No.15643919]

>>15643728
Finally someone else who knows what they're talking about.

[Anonymous No.15644030]

>>15639516
>>15639458
Kek imagine being such a smoothbrain

[Anonymous No.15644036]

>>15639867
Based

[Anonymous No.15644055]

>>15639234
I have a solution but it will take a while to properly develop it. That said, i don't think most people interested in avoiding the is-ought gap will like it. Be on the look out ~ten years from now.

[Anonymous No.15644059]

>>15641714
Not a crenulation in sight

[Anonymous No.15644089]

>>15639234

OUGHT is more immanent than IS. The former is despite not being, implicitly indestructible, the latter is only by being, implicitly destroyed.

[Anonymous No.15644124]

>>15644055
What's the solution in outline?

[Anonymous No.15644138]

>>15644089
Ok pseud

[Anonymous No.15644160]

>>15639234
>How the FUCK do we break the is-ought divide
wittgenstein might say that just because you can string words together in a way that makes grammatical sense this doesn't mean you have said something that reflects the world. this 'is-ought divide' is just words and grammar. it does not say anything real about the world.

[Anonymous No.15644177]

>>15644160
kant already said this better. fuck off 20th c

[Anonymous No.15644245]

>>15644177
Even Wittgenstein is incredibly outdated, not to mention Kant (though, admittedly, what the anon you're replying to said about Wittgenstein reveals a comical lack of understanding of anything Wittgenstein said).

You all should try reading some of the contemporary analytic literature on questions like this. A ton of progress has been made since the time of the "big names".

[Anonymous No.15644252]

>>15644245
>t. worthless academia shill
yeah keep your garbage "progress" for yourself lmfao

[Anonymous No.15644294]

>>15644124
To dissolve the divide entirely and find a road to objective morality within moral relativism, using some nifty metaphysical and epistemological turns. I wont say more than that until i have it more developed, though i do have the general argument figured out.

[Anonymous No.15644337]

>>15639234
Maybe try grounding your "oughts" in reality so you can show it's literally anything other than your opinion. Or at least that your opinion isn't fucking stupid.

[Anonymous No.15644348]

>>15644252
Cool crank.

But seriously it’s clear that most of you don’t know what you’re talking about. Just because you’ve never had sex and have read some pseud’s cliffnotes on <insert one of the five philosophers you guys have heard of here> doesn’t mean you understand anything.

Analytic philosophy is the only worthwhile thing going on in the institutional humanities these days. It’s foolish to dismiss it just cos it comes out of academia.

Take the time to understand it and you’ll see what I mean. Sure, it’s usually wrong, and often silly, but it’s the most rigorous philosophy there is and our best shot at answering these sorts of questions. The people who do it are smart—crazy smart—and know a fuckload more than you do, so you’re not gna do any better by sitting here and flinging feces with the other chimps.

[Anonymous No.15644359]

>>15644337
I’m guessing Hume thinks you can’t ground them in non-normative reality, hence the problem. Hopefully he’s wrong about this.

[Anonymous No.15644365]

>>15644348
(You)

[Anonymous No.15644431]

>>15644365
Ty my man

[Anonymous No.15644544]

>>15639234
Every state of being has a propensity of becoming

[Anonymous No.15644698]

>>15643639
>>15643670
If you had even bothered to read the
>https://www.barrymaguire.com/uploads/2/3/2/7/23270406/barry_maguire_grounding_the_autonomy_of_ethics_offprint.pdf
you would of seen on page 191 the real argument Prior put forward which is definitely not the one in the Beall paper and that you copied above. This >>15639559 commits basic logical errors

[Anonymous No.15644748]

>>15643670
>>15643728
See sections 1.1 and 2.1 of Beall's paper that explicitly refer to validity

An important example of a classically valid argument (form)that fails to be WK-valid is Addition: arbitraryAfails to implyA∨B. Acounterexample is any valuationvaccording to whichv(A) = 1 butv(B) =.5

Since you obviously have no fucking clue addition is disjunctive introduction

[Anonymous No.15644789]

>>15644698
>would of seen
AHAHAHAHA

The beauty of this one is it can't even be played off as a typo; it legit requires an acutely sloped forehead and a degree of illiteracy I can barely fathom.

But yeah I'm not a Prior scholar and have no interest in engaging in Prior exegesis. Maybe Prior really did intend something different to the argument offered by Beall and I. Who cares? I still maintain that the argument I gave refutes Hume's thesis that it's impossible to validly derive an ought from an is.

>This commits basic logical errors
Yeah, right--the "basic logical error" of reasoning in accordance to classically valid rules. It's telling that you're unable to identify these alleged errors lapsing into blathering incoherency.

Here's a test for you, kid: try to explain in your own words--no cheating and using google, ok!--what conditional proof, disjunctive syllogism and ex falso quodlibet are, and whether they're classically valid.

If you're up to the task, maybe we can talk. Otherwise everyone here is just wasting their time trying to dodge the effluence you insist on sharting into their brains.

[Anonymous No.15644814]

>>15644698
>would of seen
AHAHAHAHA

The beauty of this one is it can't even be played off as a typo; it legit requires an acutely sloped forehead and a degree of illiteracy I can hardly fathom.

But yeah I'm not a Prior scholar and have no interest in engaging in Prior exegesis. Maybe Prior really did intend something different to the argument offered by Beall and I. Who cares? I still maintain that the argument I gave refutes Hume's thesis that it's impossible to validly derive an ought from an is.

>This commits basic logical errors
Yeah, right--the "basic logical error" of reasoning in accordance with classically valid rules. It's telling that you're unable to identify these alleged errors without lapsing into blathering incoherency.

Here's a test for you, kid: try to explain in your own words--no cheating and using google, ok!--what conditional proof, disjunctive syllogism and ex falso quodlibet are, and whether they're classically valid.

If you're up to the task, maybe we can talk. Otherwise everyone here is just wasting their time trying to dodge the effluence you insist on sharting into their brains.

[Anonymous No.15644838]

>>15644789
What you gave committed basic logical errors. Prior's argument does. Assuming an arbitrary disjunction is an INVALID logical derivation. I repeatedly showed the reason why >>15640926.

>Maybe Prior really did intend something different to the argument offered by Beall and I
All you had to say is that you were wrong

>ex falso quodlibet
Actually had to look that one up. I have never seen a logic or math textbook that referred to the principle of explosion in Latin. You're an internet special whatever weird place you picked that up from makes you look stupid

[Anonymous No.15644844]

>>15644748
Lol don't care nerd. Classical logic is correct--it's the basis of all modern mathematics and many of the natural sciences too. Considerations of theoretical utility completely rule out logics as weak as the one you quote Beall discussing.

[Anonymous No.15644848]

>>15644833
Rofl the source that you were claiming I needed to read above are saying you're wrong

[Anonymous No.15644885]

>>15644838
>would of seen
AHAHAHAHA. Sorry, couldn't help myself; it's the gift that keeps on giving.

>whatever weird place you picked that up from
AHAHAHAHA it's even on the wikipedia page AHAHAHAHA sorry man this it too much even for someone who doesn't know how to read.

>Assuming an arbitrary disjunction is an INVALID logical derivation
aSSuMpTioNs arE DErivAtIoNs

So, you gna explain the rules in your own words? Or you busy researching/copy-pasting?

[Anonymous No.15644912]

>>15644885
>it's even on the wikipedia page
And now we know where you picked it up. Like I said you haven't taken a college course in logic

Are you saying you can just use an arbitrary assumption in a derivation? Again for the 4th or 5th time do you really think this is a valid derivation:

Assuming A or B
Not A
Therefore B

[Anonymous No.15644920]

>>15644848
Beall disagrees with Prior's argument, sure. Disagreeing with each other is what philosophers do. What Beall doesn't do, however, is act like a laughable simpleton and say Prior's argument is invalid because it "assumes an arbitrary disjunction" (???). In fact, he states the argument just as I stated it, and takes it to be a coherent argument that POTENTIALLY makes a very subtle error.

I actually know JC Beall, so I can show him your posts if you want his opinion. But I'm afraid you're not going to like it.

[Anonymous No.15644931]

>>15644912
Yes; it's valid. The derivation is an instance of the classically valid rule of disjunctive syllogism

From WolframMathWorld:
A disjunctive syllogism is a valid argument form in propositional calculus, where p and q are propositions:

(p v q; ¬p)/(∴q).

[Anonymous No.15644948]

>>15639234
Might makes right

[Anonymous No.15644949]

>>15644931
The valid derivation is:

Assuming A or B
Not A
Therefore if (A or B) then B

You would not pass a basic logic course

[Anonymous No.15644982]

>>15644949
I mean, I provided you the quote from WolframMathWorld, but you could always just google "disjunctive syllogism" and see that I'm right: the conclusion of this valid argument form should indeed just be "B".

While you're at it, try googling "how to contract 'would have'".

[Anonymous No.15644999]

>>15644982
I can not believe you are arguing this. You're obviously wrong if

Assuming A or B
Not A
Therefore B

is valid you can prove anything. You even came up with Latin name for the principle of explosion can't you see this is what that is? If I know any fact A using what you claim is a valid derivation I can come up with any fact B

[Anonymous No.15645663]

>>15644999
Strictly speaking, disjunctive syllogism and explosion are different rules of inference. The rule you’re calling explosion is actually disjunctive syllogism. Explosion, by contrast, is:

A
~A
———
B

But this doesn’t matter much, as the two rules are interderivable.

You keep acting like there’s something wrong with explosion though. You seem to think that if explosion is valid then you can prove anything. This is not correct. Explosion is valid in first order classical logic—a theory which is provably consistent. So the validity of explosion doesn’t result in everything being provable.

[Anonymous No.15645736]

>>15645663
Holy fuck work through it yourself. Take some Not A you know to be true:

Assuming A or B
Not A
Therefore B

That proves any fucking B you want. If that is a valid derivation all of propositional logic is fucked everything can be proven in 3 lines. If that was valid then classical logic would NOT be consistent since you can just as easily use it to prove Not B as B. But guess what the derivation you're stupidly defending as valid is NOT VALID

[Anonymous No.15645794]

>>15645736
Assuming (A or B) and (~A) of course you can prove arbitrary B. But the same is true when you assume the premises of any valid rule of inference! Congratulations, you’ve just shown that no rules of inference are valid. Ridiculous.

PS. You can easily verify all the claims I’m making: first order logic is provably consistent (Hilbert and Bernays proves this) and validates both disjunctive syllogism and explosion. No one here has any reason to take the word of an illiterate anon over one of the 20th Century’s greatest mathematicians.

[Anonymous No.15645801]

>>15645663
Ugh you know so little about this. The principle of explosion is not a rule of inference it's the name of what happens when you get a contradiction and can prove everything. The number of provable theorems explode.

Assuming A or B
Not A (Disjunctive Syllogism)
Therefore B

You're right disjunctive syllogism is used there but where the fuck does the first line come from? The actual valid derivation

Assuming A or B
Not A
Therefore if (A or B) then B (Conditional introduction)

Uses conditional introduction in the final line to account for the assumption. And notice that you can't fucking derive everything there is no explosion

[Anonymous No.15645822]

>>15645794
Again you lack even the basic logical knowledge to write the statement in propositional logic. You can not prove an arbitrary B you can prove:

if ((A or B) and (Not A)) then B
this is not just B you are extremely wrong.

>first order logic is provably consistent
I'm in full agreement with this and this another way we can know that

Assuming A or B
Not A
Therefore B

is invalid because if it was valid first order logic would be inconsistent by a simple argument that I gave above.

[Anonymous No.15645988]

>>15643650
>There's a lot wrong with this.
No, there isn't.

>First of all you don't need c) as an intermediate step in order to infer d) from a) and b). The rule of disjunctive syllogism takes two propositions of the form of a) and b) as input and spits out a proposition of the form of d).
No shit, Sherlock. None of that is relevant to the definition of a normative statement, which requires that the statement (by itself) logically entail an ought-statement.

>While your inference from c) to d) is valid, is not the inference I appealed to.
The inference you appealed to has no relevance to the definition of normative.

>In fact I'm not sure your inference has a commonly accepted name, as people tend to just use disjunctive syllogism instead.
You keep mentioning rules of inference as if they had any relevance here. The definition of normative applies to statements not sets of statements.

>The other problem is that it is not enough for c) and d) to be logically equivalent that c) entail d)--d) also has to entail c).
Why do you keep mentioning irrelevant facts? All that matters is that (c) cannot be true unless (d) is true. Therefore by definition (c) is a normative statement. That means the conjunction of two or more non-normative statements (in this case (a) and (b)) can sometimes yield a normative statement (c).

[Anonymous No.15646196]

>>15644544
so?

[Anonymous No.15646533]

>>15646196
So is ought to be

[Anonymous No.15646830]

>>15639234
Why does it matter to cross is-ought in the first place? Is opinion not good enough?

[Anonymous No.15646911]

>>15646533
Ok pseud

[Anonymous No.15646948]

>>15639337
thank you for sharing that, source?

[Anonymous No.15647630]

I don’t get it. Are you all saying that disjunctive syllogism is invalid?

I mean, that’s a view, I guess.

[Anonymous No.15647659]

>>15639382
Based categorical imperative

[Anonymous No.15647739]

>>15639867
pretty much

[Anonymous No.15647750]

>>15639234
yo this image looks like a penis

[Anonymous No.15647819]

>>15647630
No, that's not what people are talking about.. It's about normative statements

[Anonymous No.15647848]

>>15639513
Based

[Anonymous No.15647855]

It must be bridged with faith.

[Anonymous No.15648421]

>>15647819
The thought is that the (in)validity of disjunctive syllogism bears on whether normative statements can be derived from non-normative statements.

[Anonymous No.15648541]

>>15639234
Getting rid of induction. Conjecture and Criticism avoids this problem altogether. You don't derive anything from anything else. This is a form of justificationism. If you've gone down that path, you've already failed.

[Anonymous No.15648985]

>>15639234
Make things how they ought to be