In my mind, if you want to build a successful argument you need two things, evidence, and logic. The logic would simply be the mortar that holds the bricks of evidence together.
I had a discussion with someone who thinks they can prove something (non mathematical) with merely logic, and I contend that only works if you provide the evidence for the premises you use in the argument, otherwise all you have are a series of claims.
Am I wrong in this ?
That's how I view it as well. Logic is what puts evidence together in a feasible way. When it comes to the material universe, logic without evidence is useless. Without the evidence you can't prove the premise, and without an agreed upon premise the argument can't go forward.
As mentioned elsewhere ... in logic, you have ...
Tautology
Contingency
Contradiction.
We don't need any evidence to be satisfied that we know what we are talking about if we are dealing with a tautology or with a contradiction. Per reason, a tautology is right, no matter what the facts are. And a contradiction is wrong, no matter what the facts are. Facts are only important when the syllogism you are dealing with is a contingency ... because in this one case, the truth of the conclusion is actually dependent on the truth of the premises.
What Baruch said.
In addition, a syllogism is basically a declaration that a set is a subset of a larger set, then declaring an element of the subset, to conclude the element is also an element of the larger set. This yields no new knowledge. It's basically useful to check contradiction/consistency. But otherwise you need to dig new observation, or come up with a new hypothesis, subsequently verified by new evidence to make any kind of advancement.
Quote from: Termin on September 12, 2015, 04:00:29 PM
In my mind, if you want to build a successful argument you need two things, evidence, and logic. The logic would simply be the mortar that holds the bricks of evidence together.
I had a discussion with someone who thinks they can prove something (non mathematical) with merely logic, and I contend that only works if you provide the evidence for the premises you use in the argument, otherwise all you have are a series of claims.
Am I wrong in this ?
This is how I view that subject, as well.
In Why People Believe Weird Things Michael Shermer wrote
"No matter how rational, an if-then argument without empirical data to support each step in the argument is more philosophy (or protoscience or science fiction) that it is science. "
Now there is nothing wrong with philosophy as philosophy, but it is not science and shouldn't pretend to be (or maybe I should say we shouldn't pretend that it is). If you want to actually demonstrate the validity of an argument, you have to step out side of philosophy and get had data and at that point you are into science.
Sounds good, but then you have to prove the Axiom from within the function.
And there your problem lies.
jonb ... if you mean what I think you mean, and I think you do ... you leap ever so high ;-) Got a pogo stick?
What I think you mean is ... the problem of any deductive system, not only is the quality of the deductions, and the quality of the axioms (assuming we are not just tautological ... and in the case of maths we are relying on quality by definition, not by observation) what then proof of completeness and consistency from within the deductive system?
A problem for any ordinary language deduction, is the slipperiness of language ... which mathematicians work to escape thru ever more rigorous jargon. Even in that case, per Godel's Theorems ... anything even as complicated as arithmetic ... can't be both complete and consistent at the same time. The usual choice for mathematicians then is ... consistency ... with the expectation that there are valid theorems that can't be deduced. This has great consequences, not the least that it puts the ability to deduce mathematical induction (which requires arithmetic, and in fact is a deductive tool, not at all like philosophical induction from examples) from the other axioms of arithmetic out of the question ... this is similar to the fact that the parallel axiom cannot be deduced from the other axioms of Euclidean geometry. This is also responsible for the non-resolution of the Halting Problem in computation theory (that you can't prove in advance whether a given Turing machine will escape the dreaded endless loop ... you simply have to execute the program, and if it ends, then it does, if it doesn't then ... you don't know, because it might end one step past where you stop in frustration). And the Halting problem, as eloquently shown in the Imagination Game, can be used by Alan Turning to decode German messages (if the execution of the Bomb machine stops, then a proposed decode is shown to be consistent).
https://www.youtube.com/watch?v=Y7nlCdstnSg
And that leads to the means by which we are communicating right now.
You're not wrong, pogoing is second nature
(http://media.giphy.com/media/Y2r82BD06Bo0E/giphy.gif)
to a London teenager of this era.
A different Pogo ... "we-have-met-enemy-and-he-is-us" ... fortunately Jesus tells us ... "love your enemy".
(https://alwaysquestionauthority.files.wordpress.com/2014/06/10379803_655311951228911_2957886345574487560_o.jpg)
Ah, what sort of pogo are we talking about what box should we put it in?
Data is just data until we categorise it, we have to think about the sets.
I think that any system has its own rules and that is going to adjust how we see the data.
QuoteA stupid man's report of what a clever man says can never be accurate, because he unconsciously translates what he hears into something he can understand.
(http://filosofia.laguia2000.com/wp-content/uploads/2013/06/bertrand-russell-artwork-1-768x1024.jpg)
I am told by some the fabric of the universe is made from numbers, my intuition is that numbers are just a means of comparison, but I am not absolutely curtain of this, of that I am cocksure.
Yes, in so far as scientists, are acting scientific, rather than normal human ... it is all about method and data. But method encompasses not only how data is interpreted, but what is data, and what data is relevant. There is a lot of pre-processing before you even try to put data on a graph. And I have only ever addressed here, what happens after that, isn't as clean as people imagine.
"he unconsciously translates what he hears into something he can understand." ... everyone does this, and the species as a whole. A whale experiences an entirely different world than we do ... mostly acoustic. If we could see radio waves ... our radio programs would change to take advantage of that.
Quote from: jonb on September 13, 2015, 06:23:44 AM
"A stupid man's report of what a clever man says can never be accurate, because he unconsciously translates what he hears into something he can understand."
I'm not sure if that's about stupidity. All of us perceive the world through a framework that we have build since infancy. Translating into what we understand is second nature. In that case, we are all stupid. But I believe that most people want to know more, understand better - am an eternal optimist.
I wish I could still go pogoing with the Sex Pistols. :embarrassed:
I think evidence is probably more important then logic. But I'm not sure how you can have illogical evidence.
Bible thumpers proof text. Science thumpers do something similar ... ignoring evidence that doesn't fit their current hypothesis ... and sometimes ignoring what doesn't fit established theory ... this is how Chaos science was discovered in the 80s ... someone stopped looking away from contrary evidence (in regards to turbulence in its many forms). So evidence that has been proof texted by what is chosen as data, and how data is interpreted ... necessarily will agree with hypothesis or theory. The question is, what is data (this is a developing target) and how to interpret it (also a developing target)? Most of the time science colors within the lines, and can get away with it. But one can color outside the lines ... though most of the time this will lead nowhere (which seems to be the case with String Theory). Most attempts at doing something new, fail ... but we must keep on trying.
Now regarding General Relativity vs Relativistic Quantum Field Theory ... both are very good theories for what they cover ... not mere hypothesis today, as they were 50 - 100 years ago. But they are inconsistent with each other. If you try to directly merge them, you get infinite answers to your questions put to it. This is because Relativistic Quantum Field Theory is linear ... and uses very different maths from General Relativity which is also non-linear. No one in almost 100 years has been able to get past this ... partly because Quantum Theory continued to develop ... it was a moving target for the first 50 years until 1950 ... but General Relativity is basically unchanged since 1920. Since 1950 many attempts have been made, including String Theory, to paper over this inconsistency. But it would appear, for most applications, this inconsistency has no practical impact ... though perhaps near the surface of a neutron star (like at the center of the Crab Nebula) the quantum aspect and the gravitational aspect are equally ferocious.
Quote from: doorknob on September 15, 2015, 08:48:06 AM
I think evidence is probably more important then logic. But I'm not sure how you can have illogical evidence.
I think the closest you can get to illogical evidence would be to use evidence illogically.