Induction and Deduction

[evan]

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?

[Magic Poriferan]

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.

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

[evan]

Originally Posted by Magic Poriferan

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.

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]

Originally Posted by dissonance

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.

[evan]

Yes, it is always circular. "New information" is impossible. It's always just restating or rewording premises.

[Magic Poriferan]

Originally Posted by dissonance

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.

[Owl]

Originally Posted by dissonance

Yes, it is always circular. "New information" is impossible. It's always just restating or rewording premises.

Is water necessarily H20?

[evan]

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]

Originally Posted by dissonance

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?

[evan]

"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?