• You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our free community, you will have access to additional post topics, communicate privately with other members (PM), view blogs, respond to polls, upload content, and access many other special features. Registration is fast, simple and absolutely free, so please join our community today! Just click here to register. You should turn your Ad Blocker off for this site or certain features may not work properly. If you have any problems with the registration process or your account login, please contact us by clicking here.

Induction and Deduction

redacted

Well-known member
Joined
Nov 28, 2007
Messages
4,223
It seems to me that induction is really just deduction with hundreds (edit: not necessarily more than one) of hidden premises.

How is coming up with new information possible? There must be sets of rules, built through metaphor and experience that deductively lead to "novel" conclusions.

You may ask, well, how do we come up with the first premise? The answer is that it's probably genetically programmed in. Just like certain rules of language. All animals have premises about the world that they're born with.

One hidden premise in all induction is "the future resembles the past". The only way to justify this premise is with other inductive arguments which use the premise anyway. We could never come up with that premise ourselves -- no one ever questions it. It just "seems" obvious.

Sorry, those ideas were not presented in any sort of clear way... took a bunch of painkillers earlier, lol.

Thoughts?
 
Last edited:

Magic Poriferan

^He pronks, too!
Joined
Nov 4, 2007
Messages
14,081
MBTI Type
Yin
Enneagram
One
Instinctual Variant
sx/sp
The is quite open-ended philosophy here, so there is a lot I could say, but right now I feel like pointing out the biggest problem of deductive validity.
It seems to be circular, too self-contained, or basically self-affirming.

As you might know, to be deductively valid, the truth of the premise(s) must necessitate the truth of the conclusion. Generally speaking, deductivity tells us very little then. All A = B, there is A, therefore there is B. Duh. That is the simplest logical truth, but how useful is it really? All triangles have three sides. If we have a triangle, we must have something with three sides. The sentence seems silly because by saying triangle, we already said something that by definition has three sides, so the rest of the sentence is only necessary if someone didn't know the definition of triangle. It does not do anything other then affirm a definition. It's incredibly uninsightful.

So the problem is that inductive or deductive, we are never establishing a point of termination for our process of reasoning. It is true that induction could be seen as a sloppy structure of deduction, but even deduction could be seen as dependant on induction. Why do we really assume that deductive reasoning is correct? Because it's never been wrong so far. So that's inductive. :D

But wait, how do we know...? It's really an oroborose.
 

redacted

Well-known member
Joined
Nov 28, 2007
Messages
4,223
It is true that induction could be seen as a sloppy structure of deduction, but even deduction could be seen as dependant on induction. Why do we really assume that deductive reasoning is correct? Because it's never been wrong so far. So that's inductive. :D

What you say is true, but I feel I may not have explained the point I was trying to make clearly.

For example: it would be considered inductive reasoning to say, "The sun has risen every day that I've been paying attention. Therefore the sun will rise tomorrow."

But I'm saying, that's really deductive with hidden premises. If you add in the premise "Something that has happened every day for my whole life will happen tomorrow", then it's deductive.
 

Magic Poriferan

^He pronks, too!
Joined
Nov 4, 2007
Messages
14,081
MBTI Type
Yin
Enneagram
One
Instinctual Variant
sx/sp
But I'm saying, that's really deductive with hidden premises. If you add in the premise "Something that has happened every day for my whole life will happen tomorrow", then it's deductive.

Oh, it is. I was just pointing out the way that deduction can be linked back to induction. The two seem dependant on each other, which as always, leads to a circular debate ad infinitum.
 

redacted

Well-known member
Joined
Nov 28, 2007
Messages
4,223
Yes, it is always circular. "New information" is impossible. It's always just restating or rewording premises.
 

Magic Poriferan

^He pronks, too!
Joined
Nov 4, 2007
Messages
14,081
MBTI Type
Yin
Enneagram
One
Instinctual Variant
sx/sp
Yes, it is always circular. "New information" is impossible. It's always just restating or rewording premises.

Well, I think information can be individually new. That is, a single person can gain knowledge they did not originally posesses. However, anyone that's looking to "get to the bottom" of a subject is never going to achieve their goal. There is no bottom. So you could say that there is boundless new information for a person to aquire, but there is never a definitive conclusion.

Haha. Kind of a percepto-centric point of view. :laugh:
 

redacted

Well-known member
Joined
Nov 28, 2007
Messages
4,223
Well, my whole point is that premises are hidden. So if you have the premise that water is H20 stored somewhere, then water is necessarily H20. See what I'm saying?

You start with a few premises genetically encoded. And you start with the genetic capability for metaphor. Then you build up a giant web of relations of premises through metaphor.

Meh, I'm too faded right now. I'll try to reword some of what I mean tomorrow.
 

Owl

desert pelican
Joined
Feb 23, 2008
Messages
717
MBTI Type
INTP
Well, my whole point is that premises are hidden. So if you have the premise that water is H20 stored somewhere, then water is necessarily H20. See what I'm saying?

You start with a few premises genetically encoded. And you start with the genetic capability for metaphor. Then you build up a giant web of relations of premises through metaphor.

Meh, I'm too faded right now. I'll try to reword some of what I mean tomorrow.

If our first premises are merely genetically encoded, then why should we trust them? Even if the premise "water is H2O" follows from our first premises by means of metaphor (and experience), how do we know our first premises lead to necessary truths? Or any truths at all--including the possible truth that our first premises are genetically encoded, or even that there are such things as first premises?
 

redacted

Well-known member
Joined
Nov 28, 2007
Messages
4,223
"Why should we trust them?"

Well, we don't really have a choice. I mean, we cannot justify them, because in order to justify them, we must use them as premises.

A hidden premise in all induction is "the future resembles the past". There is no way to justify this premise without using it.

Rejecting that premise, though, leaves us worse off (from a pragmatic standpoint). We must just accept it, as evolution pretty much guarantees that it makes us more fit.

There is no way to get to objective truths as a human. It's a limitation we cannot get around. It's unsatisfying, yes, but what can we do?
 

Owl

desert pelican
Joined
Feb 23, 2008
Messages
717
MBTI Type
INTP
"Why should we trust them?"

Well, we don't really have a choice. I mean, we cannot justify them, because in order to justify them, we must use them as premises.

A hidden premise in all induction is "the future resembles the past". There is no way to justify this premise without using it.

Rejecting that premise, though, leaves us worse off (from a pragmatic standpoint). We must just accept it, as evolution pretty much guarantees that it makes us more fit.

There is no way to get to objective truths as a human. It's a limitation we cannot get around. It's unsatisfying, yes, but what can we do?

What if nirvana can only be only be achieved once one leaves reason behind? What if the realization that ultimate reality cannot be grasped by human reason is the first step toward the only source of lasting satisfaction?

Whether you choose to accept this or that premise depends on what you want, and what you want is determined by what you believe to be real. If you believe the world to be an illusion due to ignorance, and that becoming aware that all is one, and that therefore you are eternal, will release you from all suffering, then you will not accept that the future necessarily resembles the past, because the world in which we use this premise is illusory.

So, from a pragmatic standpoint, how do you know that you are not worse off for believing that the future will resemble the past?
 

redacted

Well-known member
Joined
Nov 28, 2007
Messages
4,223
When I say pragmatic, I'm using sort of the societal norm definition.

But yeah, there's no objective "better" or "worse" off.

It seems kinda silly not to accept that premise (that the future resembles the past), though. Without it, you can't assume that if you jump off a building you'll fall, or if you stab yourself you'll get hurt, or if you put your car in reverse it will go backward, etc.
 

Jack Flak

Permabanned
Joined
Jul 17, 2008
Messages
9,098
MBTI Type
type
Does this make sense?: Conclusions based on induction may be true; Those based on deduction are true. As long as the foundations are true, which is a maybe in "pop-logic."
 

redacted

Well-known member
Joined
Nov 28, 2007
Messages
4,223
Conclusions based on either are no more likely to be true, in my opinion. "as long as the foundations are true" is a huge huge given.

You need to use induction to get to the premises of deduction. But induction is just a form of deduction anyway...
 

Jack Flak

Permabanned
Joined
Jul 17, 2008
Messages
9,098
MBTI Type
type
In that case, it sounds like you already knew nothing was 100% certain, and I wonder why the thread was started. Once I contemplate something dry, I move on.

EDIT: Nevermind, painkillers, LOL.
 

redacted

Well-known member
Joined
Nov 28, 2007
Messages
4,223
Well, I wasn't talking about certainty. I thought it was a pretty new idea to say that induction is the same as deduction, just with hidden premises.

No one has responded to that idea, though.

(Yeah, I was definitely on some painkillers, though, lol...)
 

Jack Flak

Permabanned
Joined
Jul 17, 2008
Messages
9,098
MBTI Type
type
Well, I wasn't talking about certainty. I thought it was a pretty new idea to say that induction is the same as deduction, just with hidden premises.

No one has responded to that idea, though.
Well they aren't "the same," but you do have to take things for granted to make any decisions at all. Deduction only has one unknown: Are things as they seem? Induction has indefinite unknowns: Every case not tested. This probably wasn't the answer you were looking for, but it's all I got.
 

redacted

Well-known member
Joined
Nov 28, 2007
Messages
4,223
Yeah you missed the point. Probably means I didn't explain clearly.

My point is: induction is merely a form of deduction.

Here are two arguments that are the same, but one is "inductive" and one is "deductive":

The sun has risen every day of my life
------------------------------------
The sun will rise tomorrow (inductive)


The sun has risen every day of my life
Things that happen every day will happen the next day
------------------------------------
The sun will rise tomorrow (deductive)


My point is, they are actually the same thing. Induction just shorthands premises that we take for granted. Doesn't mean they're not there though.
 

Jack Flak

Permabanned
Joined
Jul 17, 2008
Messages
9,098
MBTI Type
type
Your second premise in your deductive argument is pure induction, so I disapprove!
 
Top