circular reasoning ok sometimes?

[Belz...]

Psalm 33:4
For the word of the Lord is right; and all his works are done in truth.

Proverbs 11:18
The wicked worketh a deceitful work

Malachi 1:14
But cursed be the deceiver


Making the world look old when it was not would be a deceitful work and therefore wicked. A work done in truth would be as it appears.

Ouch. Brilliant.

 

[aggle-rithm]

Are kings commonplace?

In 900 BCE? Yes, very much so. You couldn't swing a dead cat without hitting a king.

Of course, most "kingdoms" were smaller than most towns are today, but that is neither here nor there.

 

[tsig]

I never thought I'd see a Biblical demonstration of the non-existence of its own God, but now I have. Thank you.

We have a Universe which, when you look closely, directly contradicts all of the nonsense asserted about it in the Bible. So the Bible is a work of deception. It cannot be the product of a truthful God.

Sorry to have to break it to you guys, but it really does appear that the bible was written by ordinary people who had no idea about how the world actually works.

But if you slice off a few billion years here and take a tuck or two in space there it can all be made to fit into the bible.

 

[Seismosaurus]

Wow... I tried reading through the stuff on his blog. Reasoning really isn't his strong suit.

 

[blobru]

Wow... I tried reading through the stuff on his blog. Reasoning really isn't his strong suit.

Glancing through a couple entries - this one in particular, especially the exchange with Tony in the comments section - I get the opposite impression: he understands what reason is, the differences between logical and empirical reasoning, very well (compared to poor secular Tony, who seems to have waded into the deep end without a life-preserver or swimming lessons). The oddness of his blog comes from his literalist faith in the 'axioms' of Genesis and the conclusions that entails (of course that sort of faith is irrational from the get-go, though I gather he means to defend it as the only coherent and thus possible world-view). Anyway, at least in the little I've read, reasoning is his strong suit; with faith its straight-jacket.

 

[Brainache]

Others have already responded to this, but I'll give you my answers, since you asked me...

Can you please provide an example of at least one such nonsense.

The entire book of Genesis, for a start, but if want a specific example: Noah's Ark is a story obviously stolen from Babylonian traditions and is a physical/biological/geological impossibility.

Well, it provides us with a list of names of peaple wrote it. Of course some might have emplyed scribes to write as they dictated. Were they all ordinary?

As I am The Scum pointed out, I meant non-supernatural entities. They certainly didn't demonstrate any god-like knowledge of Cosmology. They thought they lived on a flat earth covered by a dome of water!

Let’s go with what is commonplace.

Are kings commonplace? Solomon and David were both kings and the books attributed to them are Psalms, Ecclesiastes, Proverbs, Song of Solomon.

Were people raised in Pharoah’s family and educated there commonplace?

Moses was and the books attributed to him are Genesis, Exodus, Leviticus, Numbers Deuteronomy.

Luke was a 1st-century physician.
Were 1st century physicians commonplace?
The books he wrote are Luke and Acts.


I fail to see how such people were or are commonplace

And I fail to see how such people are in any way magically communicating with an invisible man who made the world.

How is how the world works relevant to the biblical salvation-of-mankind-via- a- Ransom Sacrifice theme? Just curious to see how you attempt to conjoin them.

Because in the real world, as opposed to the Bible fantasy one where you live, nailing a 1st century Jewish preacher to a stake had nothing to do with me. He didn't die for my sins, he died because he defied Roman authority at a time when doing so was dangerous.

And, personally I find the idea of profiting from the suffering of others morally repugnant.

 

[Brian-M]

So, you're happy to accept the axioms and rules of inference of logic as merely very, very likely to be true?

After all, as we know, induction (i.e., appeal to experience) yields merely probable, not certain, conclusions. So, you accept the claim that, "It is very, very likely, almost but not quite certain, that '(P and Q) implies P' is true?"

Because I find that rather more certain than almost certain.

Hmmm... good point. And it's amusing to imagine textbooks filled with that kind of uncertainty.

 

[I Am The Scum]

Forgive me for continuing a derail, but this is one big assumption about the Bible that needs to go away: It is a bit of a stretch to say that because one of the books is named "Luke," that it was written by Luke the disciple. Same goes for Matthew, Mark, etc... The truth is, the authors are unknown.

 

[angrysoba]

No, so I could be wrong.

But you can empirically demonstrate basic arithmetic quite easily. If you want to demonstrat that two plus two equals four, you just put two objects in a container, add two more objects, then add them up. You can demonstrate things like cube roots a similar way. You can prove that the cube root of styrofoam is three by sticking toothpicks in twenty-seven styrofoam balls to build a 3x3x3 cube. You can demonstrate things like calculus with analog devices that use physical material, such as water.

Even more abstract things have real-world applications. For example, imaginary numbers. When you're calculating the impedance in an AC circuit you use real numbers for resistance and the Y-axis imaginary numbers for reactance. And it works. You know the logic of imaginary numbers is valid because the logic applies in real-world situations.

Even abstracts with no direct real-world applications can be tested by or applied to logic which has either been tested directly in reality or tested by other logic which has itself been tested in some way.

Or can you give me examples of instances of pure maths that are conceptual islands, that does not utilize logic that can be verified by being applied, either directly or indirectly, in real-world situations to see if it holds true?

I don't know how you can argue that all mathematical equations are tested empirically. If we accepted the idea that this is true then we may find ourselves with some unhelpful conclusions.

For example, you argue that to test 2+2=4 you can put two things in a bag and then add two more things and then add them up. Are you serious? What would happen if I gave you four knobs of butter or chocolate and they melted? Would we then say we have falsified basic arithmetic? If not then what purpose does your demonstration serve?

Similarly, how can you demonstrate theorems such as Fermat's Last Theorem empirically? By its very nature it cannot be demonstrated empirically:

According to Wiki it is formulated as follows:

no three positive integers a, b, and c can satisfy the equation aⁿ + bⁿ = cⁿ for any integer value of n greater than two.

If this is an empirical equation then it will always remain an open question. Sure, if n is 17 it may turn out to be true every time we test it, but what if it is 365 or 10,798 or 111,111,111,111 or 999,999,999?

Or even simpler, how can we know that numbers are infinite? We could keep counting and then finally get to the biggest number.

 

[Kopji]

well here here is a "trilemma" from Lisle i think you guys will find it well...... head scratching
What is your answer to the trilemma? (A) logic is unjustified (accepted by blind faith). (B) logic is justified by something illogical (irrational). (C) Logic is justified by logic (circular). What is your answer?

Logic is justified because it works. This sounds trivial, but it is at the core of why I say say he spouts nonsense.

Karl Popper spent some time drawing pictures of this in a book he published - "On the sources of knowledge and ignorance". He compares two different concepts.

Philosophically UN-important

Ideas that is
Designations or terms or concepts
may be formualted in
words
which may be
meaningful
and their
meaning
may be reduced, by way of
definitions
to that of
undefined concepts
the attempt to establish (rather than reduce) by these means their
meaning
leads to an infinite regress


Philosophically ALL-important

Ideas that is
Statements or propositions or theories
may be formualted in
assertions
which may be
true
and their
truth
may be reduced, by way of
derivations
to that of
primitive propositions
the attempt to establish (rather than reduce) by these means their
truth
leads to an infinite regress

"In matters of the intellect, the only things worth striving for are true theories which come near to the truth."

Karl Popper
(even to 8th graders lol)

So my challenge I guess, would be to stop talking about words like logic and start defending what he is promoting as being true or not. If his assertions are not falsifiable (we cannot evaluate their truth compared to something else) they are not worth our time. The world was created five minutes ago and he is free to use whatever tools he has to prove that statement false.

If the truth is not in him, then fine, he can chat about if logic is circular but it is a bit like arguing about the letters that make up words.

 

[Brian-M]

For example, you argue that to test 2+2=4 you can put two things in a bag and then add two more things and then add them up. Are you serious? What would happen if I gave you four knobs of butter or chocolate and they melted?

You would still have four times the weight.

Similarly, how can you demonstrate theorems such as Fermat's Last Theorem empirically? By its very nature it cannot be demonstrated empirically:

I'm not claiming everything can be tested empirically. But the forms of logic you use to test the abstracts that cannot be tested empirically can either themselves be shown to be functional by applying them to empirically demonstrable situations, or be examined with other forms of logic which can be.

I'm not even saying that the forms of logic that can be shown to be functional by applying them to empirically demonstrable situations can be proven this way (phiwum pointed out the absurdity of this). Only shown to be useful and generally valid.

 

[Chernobyl X1]

Can you please provide an example of at least one such nonsense.

How about where this god created the Earth (Gen 1-1) and plants (Gen 1-11), before creating the Sun and moon at the same time (Gen 1-14)?
Also considering the Moon as a "light" is quite nonsense.

 

[Soapy Sam]

. You know the logic of imaginary numbers is valid because the logic applies in real-world situations.

Does this really hold true?
Logical explanations of observable phenomena may be utterly wrong, yet because we have observed the phenomena- and because they repeat, we still get the predicted answers.

An example is the assumption that there exists a sphere of "fixed stars". This is wrong, but works pretty adequately for navigation.

 

[Dinwar]

I don't know how you can argue that all mathematical equations are tested empirically.

Solve this equation without resorting to empiricism and I'll agree you may have a point. And if the equations can't be tested empirically, that means they can't be tested. Which means they have no bearing on the real world.

As for circular reasoning....kinda.

You have to assume basic axioms in order to make a system of logic work. Logic is GIGO, and you need to assume something in order to have any initial input.

The thing is, you don't have to JUST assume that first something. You can assume multiple somethings. This means that you can test the assumptions against each other to see if the system remains sound. For example, non-Euclidian geometry was found by holding everything true except the Parallel Postulate. Once you've demonstrated that the logic is consistent, you can test it against the real world. If they pass, you can make those assumptions moving forward.

well here here is a "trilemma" from Lisle i think you guys will find it well...... head scratching
What is your answer to the trilemma? (A) logic is unjustified (accepted by blind faith). (B) logic is justified by something illogical (irrational). (C) Logic is justified by logic (circular). What is your answer?

Logic is justified by experience, and refusing to acknowledge an answer doesn't render that answer invalid. No saying that you did, wakawakawaka--but Lisle certainly ignored a potential answer.

 

[phiwum]

Solve this equation without resorting to empiricism and I'll agree you may have a point. And if the equations can't be tested empirically, that means they can't be tested. Which means they have no bearing on the real world.

I've no idea what you want us to do when you say, "solve this equation".

But, no, mathematics is not tested empirically. The appropriateness of a particular mathematical model of a physical system may be tested, but a mathematical theory is not tested in the sense you suggest.

As for bearing in the real world, a mathematical theorem can be viewed as a kind of conditional statement: In any interpretation of the terms such that these axioms are true, this theorem will also be true. This is generally regarded as something like an analytic truth. We don't test such things, just as we don't take surveys in order to determine what percentage of bachelors is unmarried.

The thing is, you don't have to JUST assume that first something. You can assume multiple somethings. This means that you can test the assumptions against each other to see if the system remains sound. For example, non-Euclidian geometry was found by holding everything true except the Parallel Postulate. Once you've demonstrated that the logic is consistent, you can test it against the real world. If they pass, you can make those assumptions moving forward.

First, you cannot show that most interesting mathematical theories are consistent, though you can show that they are relatively consistent (e.g., if Euclidean geometry is consistent, then so is spherical geometry).

Second, there is no requirement to test the theory "against the real world", just so long as we view it as a purely mathematical theory. No one has proposed testing, for instance, the axiom of choice in the physical universe, and for good reason. Nonetheless, it's a perfectly acceptable mathematical axiom (a few idiosyncratic objections notwithstanding).

You seem to be conflating mathematics and its applications in scientific theories or models of physical phenomena. It's a very old-fashioned notion. No one doing real math these days argues about whether the axioms are "true" or tests them against the real world.

Logic is justified by experience, and refusing to acknowledge an answer doesn't render that answer invalid. No saying that you did, wakawakawaka--but Lisle certainly ignored a potential answer.

Nonsense!

If logic were justified by experience, then we should have to admit that the axioms are merely very, very probable, but not certain. As we all know, induction (i.e., appeal to experience) yields merely probable claims.

Thus, you are committed to the view that it is almost, but not quite, certain that, for instance, "(P and Q) implies P". You have to be ready to admit that there is some non-zero probability that this axiom is false, if the only reason you accept it is experience.

For myself, that axiom is certain, beyond any doubt whatsoever. Consequently, it cannot be the case that experience is the source of its justification.

 

[kellyb]

well here here is a "trilemma" from Lisle i think you guys will find it well...... head scratching
What is your answer to the trilemma? (A) logic is unjustified (accepted by blind faith). (B) logic is justified by something illogical (irrational). (C) Logic is justified by logic (circular). What is your answer?

(D) logic is justified by observation

This is the whole crux of science. We're not all sitting around chatting on the internet on computers via the magic of presuppositional faith in physics. We can observe that the technology works.

 

[phiwum]

(D) logic is justified by observation

This is the whole crux of science. We're not all sitting around chatting on the internet on computers via the magic of presuppositional faith in physics. We can observe that the technology works.

Nonsense.

Tell me what observations confirm "P implies (P or Q)".

Tell me also how to determine whether an observation satisfies an axiom without using modus ponens or modus tollens. You really can't even discuss confirmation without using some basic logic, so logic must precede empirical testing.

Finally, as I've said previously, the basic logical axioms gain no probability from confirming observations. I would be more willing to believe that every memory and experience I've ever had is just an illusion, that nothing I've ever seen was real, than that "(P & Q) implies P" is false.

Observations do not serve as the basis for our faith in logic.

 

[kellyb]

Nonsense.

Tell me what observations confirm "P implies (P or Q)".

Tell me also how to determine whether an observation satisfies an axiom without using modus ponens or modus tollens. You really can't even discuss confirmation without using some basic logic, so logic must precede empirical testing.

Finally, as I've said previously, the basic logical axioms gain no probability from confirming observations. I would be more willing to believe that every memory and experience I've ever had is just an illusion, that nothing I've ever seen was real, than that "(P & Q) implies P" is false.
Observations do not serve as the basis for our faith in logic.

Well, yeah, we can't "prove" that we're not brains in a vat and that 1=2. In fact, I'd say you'd need something like the former to be true for the latter to be the case.

But back in the world we live in, 1=1 and 1+1=2, and we have the technology to demonstrate the practical usefulness of math and the other observation-based sciences.

 

[phiwum]

Well, yeah, we can't "prove" that we're not brains in a vat and that 1=2. In fact, I'd say you'd need something like the former to be true for the latter to be the case.

But back in the world we live in, 1=1 and 1+1=2, and we have the technology to demonstrate the practical usefulness of math and the other observation-based sciences.

You are missing the real point of my post. I didn't say I think that it's possible that 1 = 2. I said the axioms of logic are more certain than any experience can ever be.

I think you should re-read my post. My point is that a simple logical axiom like "(P & Q) implies P" is not verified by experience, because it is a certainty. Any appeal to experience would yield, at best, that it is very, very likely, but not certain, that "(P & Q) implies P".

To put it differently, your claim results in accepting that there is a non-zero probability that 1 = 2. I don't agree (at least not when we speak of logic rather than mathematics).

Please, respond to the actual point of my post, rather than being diverted by the brain-in-a-vat bit.

 

[kellyb]

You are missing the real point of my post. I didn't say I think that it's possible that 1 = 2. I said the axioms of logic are more certain than any experience can ever be.

.

How do we know that the axioms of logic are more certain?

We we deduce (and observe) that logic "works", or presuppose it?