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Tarskian

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All three laws are allowed. I just pointed out that there are issues in assuming two of them.
July 26, 2024 at 09:17
That is what Hawking has said on the matter: Isn't it rather your own criticism that is ridiculous?
July 26, 2024 at 09:14
That is not what I said. Straw man.
July 26, 2024 at 09:00
"the sentence or its negation is a theorem" ignores the existence of true but unprovable sentences. So, it should rather be "the sentence or its negat...
July 26, 2024 at 06:15
You can perfectly know the construction logic of a system but that does still not allow you to know its complete truth. So, even if we manage to figur...
July 26, 2024 at 05:59
The most problematic foundational law in logic (Boole's "laws of thought") is in my opinion the law of the excluded middle (LEM), which implicitly ass...
July 25, 2024 at 07:09
The natural speaker assumes that there is somewhere some justification. Formal languages may expect that too. That is actually the main difference bet...
July 24, 2024 at 05:18
The best example of popular delusion is their demand to "tax the rich". The core of the wealthy class are the ruling mafia themselves, along with the ...
July 24, 2024 at 04:25
Science discovers, expresses, and duly tests stubborn patterns observable in the physical universe. The resulting output of scientific activity are sc...
July 24, 2024 at 03:30
In my opinion, the Republicans remain firm supporters of the principle of rule by the mob, i.e. democracy. They are not "true" conservatives at all. S...
July 24, 2024 at 03:09
A revolt by foreigners? Because that's 90% of the population. Theyd rather jump on the first plane out of there. The Emirati themselves are too much p...
July 23, 2024 at 05:25
I view Emirati with respect. I may not always agree with all the nitty gritty details of what they are doing but on the whole I consider their post-oi...
July 23, 2024 at 03:42
The Dubai Emirati do not pay for education, healthcare, housing , or retirement benefits for the 90% foreigners of their population. All of that are n...
July 23, 2024 at 03:34
Dubai doesn't live of oil today already. What you are seeing today, is already their post-oil strategy. There are 3.3 million people in Dubai of whom ...
July 23, 2024 at 03:26
Totally agreed. I give to less fortunate relatives and to people that I can physically see around me. I consider everything else to be an online scam ...
July 23, 2024 at 01:51
I don't think that the people in Leiden or Bologna want to turn their neighboring countryside into a concrete jungle of endless suburbs. Wealthy peopl...
July 22, 2024 at 23:31
No, not because they are in the desert. Because they don't need to give out handouts in order to expand. And where are they going to grow the food, if...
July 22, 2024 at 22:54
Anonymous moral advice is the best, actually. It is a question of establishing an almost "cryptographic" protocol. When moral advice is justified, I'd...
July 22, 2024 at 22:40
The global poor want to move there because they can get handouts, i .e. free housing, free healthcare, free education, welfare benefits, and so on. Wh...
July 22, 2024 at 22:11
The Emirate of Dubai offers just one product, which is globally tremendously and increasingly popular, i.e. freedom from the aberrations caused by dem...
July 22, 2024 at 21:06
Exactly. It represents an entailment A ? B, and not just a simple implication A?B. Logic makes all its decisions by only looking at truth values while...
July 22, 2024 at 20:04
According to the page on the subject, determinism and predeterminism are "closely related": If you believe that everything has a reason, it does not m...
July 22, 2024 at 11:18
For Jews: Mosaic law ? isMoral(behavior) For Muslims: Islamic law ? isMoral(behavior) As far as I know, everyone else does not have enough of a docume...
July 22, 2024 at 10:41
It is probably a mixup between the implication, which is just a truth table, and the entailment, a ? b, which means that consequent b necessarily foll...
July 22, 2024 at 10:21
"(2+2=5) implies (Kamala Harris is prime minister of China)" is also true in classical logic. It actually does. It just means that knowledge as a just...
July 22, 2024 at 09:51
Singer wants us to give money to Oxfam, because the girls in Haiti are clamoring for more.
July 22, 2024 at 09:43
Eventually, you will even need to add quantifiers (? ?) and predicates to express in logic something as simple as: All humans are mortal. Socrates is ...
July 22, 2024 at 08:07
1) Religion matters. Agreed. Humans seem to need spirituality as well as a definition for morality. 2) Some truth can be obtained by practicing religi...
July 22, 2024 at 07:47
In my experience, democracy is a severely flawed system. You can easily find a democratic majority for ideas that sound good but that are otherwise su...
July 22, 2024 at 03:44
I agree with the following comment: I disagree with the following comment: That is only going to make the problem worse. In my opinion, it is preferab...
July 22, 2024 at 01:18
The original article that establishes and proves the bi-interpretability: I have already linked to this original publication in a previous comment. Th...
July 22, 2024 at 01:06
I did. I wrote: "There are sentences that are like this. There are sentences that are like that. Both could exist." There's a lot of syntactic noise a...
July 21, 2024 at 07:35
There exist sentences that are true or there exist sentences that are false, or both. "Or both" means: Potentially, there exist as well true as false ...
July 21, 2024 at 06:20
I left out that detail because it is obvious. So, with the details: It is more accurate but also much more impenetrable than: The resulting syntactic ...
July 21, 2024 at 05:59
It has always been an explanation about the diagonal lemma: S <-> ¬F(r(#S)) Meaning: (S ? ¬F(r(#S)) ? (¬S ? F(r(#S)) Meaning: (S is true and F is fals...
July 21, 2024 at 04:29
P(S) := S <-> S Is indeed impossible in PA. However, you can implement it as: P(n) := n=n The diagonal lemma is still perfectly satisfied for the iden...
July 21, 2024 at 03:26
That is just how logic works. Asserting: . S ? L Means: S is true and L is true.
July 21, 2024 at 03:16
That is the same. A formula that takes a sentence as argument is a property of that sentence.
July 21, 2024 at 03:14
First, we replace F by ¬F. If F is a property then its negation is also a property. So, the following is an equivalent statement: Next, we replace S <...
July 21, 2024 at 03:07
I wrote that about the diagonal lemma, i.e. Carnap's theorem. Of course, there are conditions for when it applies. The context required, is PA or equi...
July 21, 2024 at 02:27
The identity predicate in PA is: P(n) := n = n It cannot be implemented as: P(S) := S <-> S You are trying to do something that is not supported in PA...
July 21, 2024 at 01:02
In arithmetic theory, the argument n in P(n) must be a natural number. You cannot apply the predicate to S. You can only apply it to its Godel number....
July 21, 2024 at 00:39
I guess you meant to write: Let P be the property: P(S) if and only if S is equivalent with P(#S). In that special case, P is actually Tarski's truth ...
July 21, 2024 at 00:22
The diagonal lemma: (By the way, there seems to be a mistake in the page: "formula" should be "sentence"). Equivalently replace F by ¬ F: ? ? ¬ F(°#(?...
July 20, 2024 at 23:28
Take for example Oxfam, known for exchanging sex for access to taxpayer-funded aid: Highly-paid expensive expat jobs just for westerners while the loc...
July 20, 2024 at 14:51
That is a bit of a mystery. Any simplification to Robinson's arithmetic will make it complete: https://en.wikipedia.org/wiki/Robinson_arithmetic. It j...
July 20, 2024 at 00:35
Skolem Arithmetic only has multiplication (no addition) and is also complete. The problem occurs when you try to add both addition and multiplication.
July 19, 2024 at 19:00
My initial interpretation of the term "better" was "more faithful", but indeed, this doesn't necessarily make an abstraction more useful. That does in...
July 19, 2024 at 12:37
Noson Yanofsky's paper, "True but unprovable", is about arithmetical truth, also called "true arithmetic": I have used the term "mathematical truth" i...
July 19, 2024 at 08:17
There's a big difference between saving a child from drowning in a pond and giving money to people who say that they will be saving drowning children ...
July 19, 2024 at 01:27