Is there any reason at all to trust deductive reasoning other

>>7974038
>just because 2+2 was 4 yesterday doesn't mean it will be 4 tomorrow
>it's inductive
Yeah. OK. >>>/kimisbestwaifu/

>>7974121
You haven't provided any arguments.

Any deductive theory is only trusted when used to model the real world only because it made valid predictions before. This is the case for arithmetic, for example. We can use it to make valid estimations and predictions.

And yes, 2+2=4 is only to be trusted because it is justified inductively. We can use this arithmetic statement in order to make predictions. Say, if we add 2 and 2 kilograms of something, we get 4 kilograms. It always was the case, so we trust this kind of reasoning.
On the other hand, if we had some useless logical formalism which was completely contradictory to the real world, we wouldn't trust it to make predictions about the real world.

Classic logic was proven wrong in some domains of physics, by the way. Take quantum mechanics as an example:
https://en.wikipedia.org/wiki/Quantum_logic

>>7974137
Arguments are wasted on retards.

>>7974137
2+2=4 arises from how the addition operation is defined, your logic is about its application to physical examples but 2+2 would remain 4 regardless what the total mass of 2 bags of 2kg put together is and there were many areas of maths that were researched and discovered with no intention of them having any practical applications. Most of them end up doing so because mathematical logic appears to underpin the universe, but statements in pure mathematics that are derived deductively are true and would remain so no matter what observations you could make about any failure in their ability to describe physical reality.

>>7974185
Have you even read my argument? I'm not talking whether we as humans consider some model to be true. I could make up any formal system with a set of completely insane axioms, inference rules and definitions and derive theorems and my own branch of mathematics from it, that would be held true in my system.

My argument is about the use of deductive reasoning to make deductions about empirical data (the real world). Please read the OP before replying with such freshman-level redundant idiocy.

>>7974185
>Most of them end up doing so because mathematical logic appears to underpin the universe

[Citation needed]

There's no single mathematical logic. There are countless different formal systems with their own mathematics. And what we know of as classic, intuitive logic is in no way special - it had been shown not to work for making predictions about the real world in the past.

Read this:
https://en.wikipedia.org/wiki/Quantum_logic

And this:
https://en.wikipedia.org/wiki/Qubit

>>7974247
Your response doesn't make any sense. It's disorganized schizophrenic rambling - seek help.

>>7974214
>My argument is about the use of deductive reasoning to make deductions about empirical data (the real world).

It is not valid to use deductive reasoning to make deductions about empirical data, at least in the sense that it is not valid to use deductive reasoning to determine what is "true", or what merely corresponds to objective reality. One may validly use existing philosophical principles (deductive reasoning), to determine what explanation is the best, but that is it.

>>7974038
>Is there any reason at all to trust deductive reasoning other than the fact that it is justified inductively?
It is not justified inductively, or at least not legitimately.

>Same seems to be the case for the scientific method - we only trust it because it worked in the past (therefore, there's only an inductive justification for it - nothing more).
The scientific method is a process, not a static body of facts, so it doesn't make sense to say that it can be justified.

>We can make deductive arguments for the use of scientific method, but deduction itself is justified by inductive reasoning.
No, or at least not legitimate ones. Deduction is not justified by inductive reasoning.

>>7974137
>Any deductive theory is only trusted when used to model the real world only because it made valid predictions before. This is the case for arithmetic, for example. We can use it to make valid estimations and predictions.
I don't think you understand what "deductive" means.
>And yes, 2+2=4 is only to be trusted because it is justified inductively.
No, it is "justified", because it follows from particular mathematical principles.
>We can use this arithmetic statement in order to make predictions. Say, if we add 2 and 2 kilograms of something, we get 4 kilograms. It always was the case, so we trust this kind of reasoning.
That's not a falsifiable prediction, that is merely a subtle tautology.

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>>7974038
what you call deduction is just the application, to statements, of inference rules that you qualify as deductive. but of course, both the statements and the inference rules are inductive. Anything stemming from your imagination is inductive. your whole imagination has the task to dwell in induction.
Induction is just separating things in trying to see what resembles what and what differ from what.
the things whereon you speculates are what you feel, but equally what you think.
to any output of your imagination, there is an affect which means that you like it, you do not like it, or you do not care.
when it comes to the imagination, what you like is called ''it makes sense'' and what you do not like is called ''it does not make sense''


the problems of the people who have faith in their fantasies, in their imagination, in order to gain access to some fantasy of ''higher reality'', is that they know that inductions are personal. But the task of the rationalist is to believe that a structure is hidden somewhere, because one day the rationalist chose to have the thought that all this similarity and lack of chaos must hold at any time anywhere, and that this structure the ultimate reality.
so rationalists despise inductions and knowing this, while still clinging to their childish fantasy of ''objectivity'' and what not, they choose to invent a new class of ''products of their imagination'' which is ''the deductions''.
Their task now is to consider all the outputs of their imagination, to get rid of as many inductions as possible, to cram as many deductions as possible in their ''structure''.

>>7974925

of course, rationalists are not happy to hear that all their fantasies, not matter how formalized, are just fantasies and they get very butthurt once you ask them to substantiate their claim that their speculations give indeed access to some non-subjectivity, when you ask them why their speculations matter, to them, to anybody else but them...

The best part is that rationalists, typically the scientists, do not even know why they choose to cling to their fantasies.
You can ask any scientist why he does what he do each day, and he will not be able to tell you, besides loving to be paid to speculate. What this says is that speculations call for speculations. There is no end to your fantasies, because the end of your fantasies, the reach of whatever reality you seek remains a fantasy itself.

>>7974214
>freshman-level redundant idiocy
>implying that's now what you posted in the OP
Earn your debate partner. If your argument is sophomoric crap, expect that to be the response.

>>7974927
so why the love for speculations and the hate for empiricism (aka, for the rationalist, the chaos, sterility, non-speculation) ?
Well it turns out that your speculations relates to your love of hedonism. The problem of hedonism is that you must have the means to get pleasures AND you must fight boredom.
Your imagination serves your love of pleasures and hate of pains. You dwell in the past to have a better future, because you dislike what you feel and think so far. Your life sucks and you think that there ''must'' be a way to make it better.
Of course, ''making it better'' means having an easy life, which is why people love the scientists for bringing them computers and houses and tomatoes in winter.

Now you seek a reason why we cling to our deductions. The nice things about deductions is that people think that the notion of necessity and objectivity are reached through deductions. This feeds their deliriums of seeking a reason of their shitty life.
But what they refuse to see is the failure of their endeavour. Deductions do not work. When you try to fix your discomfort, after you imagined that you can get comfier, you may or may not erase this temporary discomfort, but discomfort re-appears again sooner or later. Even with pure pleasures, you see your speculations always failing to make your pleasures last.
This is what happens so far
-fear death, dislike your life
-create gadgets to live longer because you fear death, dislike your life
-even with all the gadgets you still fear death, dislike your life
-claim that technology makes your life better, even though you still fear death, dislike your life

>>7974955

The underlying fantasy of the rationalist is that they can better themselves, and the whole humanity, in fixing his discomfort. They refuse to see that if you have car, thanks to the scientists, you equally have all the problems tied to a car.
You can built a wall in assembling rocks. IF you do it twice and that you like the result, you think that the wall will last forever and that piling rocks will satisfy you, always. And you whine like a child when your wall is torn apart or if you cannot even construct your wall.

They refuse to see that trying to feed your hedonism never ever gets you what you want: some permanent pleasures. each rationalist still thinks that, no matter all the failures in their lives, no matter the failures of other people for decades, for centuries, for millennia, he thinks that he can do better. He clings to his fantasy of success. Why because? because he has no idea how to do something different. He even claims that his way is ''necessary'' because he his not able to think otherwise.

The good news is that you get happiness once you stop having mental proliferations, once you stop clinging to your hedonism, but the rationalists love to talk for the sake of talking, so they despise this fact.
The best way to fix your discomfort is not through trying to fix it in moving around and speculating about the changing the world and creating stories about the world, but the solution is to change your attitude towards what you feel and think.

>>7974038
>deductive reasoning ... is justified inductively
wat

>>7974185
>but 2+2 would remain 4
only if you do the proof each time you use it

>>7975861
and if you do not make mistake

and carry the proof fully

>>7974344
>Deduction is not justified by inductive reasoning.
It is rather that the justification is not defined outside the few formal languages for deduction that we have today.

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reminder that a few people believe in knowledge of causation through only one event.

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>>7974038
This thread again. Were you not content with the comprehensive public slaughtering your drivel was given last time?

>>7980757
sauce ?