How do nominalists account for the laws of logic?

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Reply Sat 27 Mar, 2010 11:18 pm
How do nominalists account for the laws of logic?

I'm no expert, but it seems to me the laws of logic are universal; and they are certainly not material.
So if you don't believe in abstract objects how do you account for them?
 
ughaibu
 
Reply Sat 27 Mar, 2010 11:33 pm
@spiltteeth,
Logics are formal systems, what is it that you think needs to be accounted for?
 
spiltteeth
 
Reply Sat 27 Mar, 2010 11:53 pm
@ughaibu,
ughaibu;145049 wrote:
Logics are formal systems, what is it that you think needs to be accounted for?


Well, like I say, I'm no expert but Logical absolutes are conceptual by nature, but I don't see how they are dependent on space, time, physical properties, or human nature etc
They are not the product of the physical universe (space, time, matter), because if the physical universe were to disappear, logical absolutes would still be true.
Logical Absolutes are not the product of human minds, because human minds are different, not absolute.
But, since logical absolutes are always true everywhere, and not dependent upon human minds, they must be an abstract nonmaterial object.

What do nominalists say?
 
ughaibu
 
Reply Sat 27 Mar, 2010 11:56 pm
@spiltteeth,
spiltteeth;145057 wrote:
since logical absolutes are always true everywhere, and not dependent upon human minds, they must be an abstract nonmaterial object.
I dont see any reason to accept this. How do you explain the completeness of different logics?
 
amist
 
Reply Sun 28 Mar, 2010 12:05 am
@spiltteeth,
Quote:
I dont see any reason to accept this.


If you see no reason to accept that logical absolutes are always true everywhere then have you really been far even as decided to use even go want to do look more like?
 
ughaibu
 
Reply Sun 28 Mar, 2010 12:08 am
@amist,
amist wrote:
if you see no reason to accept that logical absolutes are always true everywhere then have you really been far even as decided to use even go want to do look more like?
日本語で言えば意味もあるし。
. . . .
 
Deckard
 
Reply Sun 28 Mar, 2010 12:22 am
@ughaibu,
It seems Kant would help us here but don't know Kant well enough to speak with any authority. The antynomies arose when reason was attempted beyond the phenomenal realm.

The term antynomy acquired a special significance in the philosophy of Immanuel Kant (1724-1804), who used it to describe the equally rational but contradictory results of applying to the universe of pure thought the categories or criteria of reason proper to the universe of sensible perception or experience (phenomena). [from wiki]

So something is going on here regarding the limits of logic. I think Kant is called a nominalist in most circles.


Quote:
Kant was a nominalist; although his philosophy would have been rendered compacter, more consistent, and stronger if its author had taken up realism, as he certainly would have done if he had read Scotus.
--- C.S. Peirce
Peirce - Philosophy: Nominalism

For Kant the laws of logic were phenomenal. That is how he accounted for them.
 
spiltteeth
 
Reply Sun 28 Mar, 2010 12:26 am
@ughaibu,
ughaibu;145059 wrote:
I dont see any reason to accept this. How do you explain the completeness of different logics?


I don't know, but they all have laws/principals. So if any of them is true you need some abstract absolute, and if all of them are wrong you have to use the very laws of logic in question to disprove them!

Are there any logics that deny the law of contradiction? So that A and Not A can be the same?

I thought this was pretty universal, are there any cultures that can say 'it is raining outside my window' and 'it is not raining outside my window' are both logically true?
 
ughaibu
 
Reply Sun 28 Mar, 2010 12:32 am
@spiltteeth,
spiltteeth;145070 wrote:
I don't know, but they all have laws/principals. So if any of them is true you need some abstract absolute, and if all of them are wrong you have to use the very laws of logic in question to disprove them!
I dont see any need for abstract objects, but I guess it depends on what you mean by these. Logical truths are true by virtue of the rules of a formal system, they needn't be true or representative of anything outside that system.
spiltteeth;145070 wrote:
Are there any logics that deny the law of contradiction? So that A and Not A can be the same?
Yes, paraconsistent logics do, to varying extents.
 
Deckard
 
Reply Sun 28 Mar, 2010 12:33 am
@spiltteeth,
spiltteeth;145070 wrote:

Are there any logics that deny the law of contradiction? So that A and Not A can be the same?

Kant's logic, specifically in the case of the antinomies. Or rather when logic is extended beyond the phenomenal realm. Which to me suggests some sort of unknowable noumenal logic that resolves the antinomies. Enter Hegel (another nominalist).
 
jeeprs
 
Reply Sun 28 Mar, 2010 12:43 am
@spiltteeth,
spiltteeth;145038 wrote:
How do nominalists account for the laws of logic?

I'm no expert, but it seems to me the laws of logic are universal; and they are certainly not material.
So if you don't believe in abstract objects how do you account for them?


I am not an expert in this either, but I am curious as to how mathematics is both logically true, and also predicts the characteristics of the universe so accurately. (Last time I brought this up, ughaibu said 'so what?' as he has said here.)

I can't see why 'mathematical realism' is not true. I am also inclined to think that platonic realism is true. I think the really hard question comes around when you try and account for 'where' these 'real objects' (and numbers) 'exist'.

As indicated by the quotations, I don't think they exist anywhere, but I think they have something to do with the way things exist. The laws of logic and math are predictive of reality, because reality itself is lawful and mathematical. But empiricism (it seems to me) can never admit that idea, because it is too much like rationalism.

Check out a book called the Mathematical Mystery Tour by A K Dewdney. There is a description on Amazon.

I am interested in discussing this question further, bearing in mind I have almost no background in any of the formal disciplines that it is based on .:Not-Impressed:
 
spiltteeth
 
Reply Sun 28 Mar, 2010 12:43 am
@Deckard,
Deckard;145068 wrote:
It seems Kant would help us here but don't know Kant well enough to speak with any authority. The antynomies arose when reason was attempted beyond the phenomenal realm.

The term antynomy acquired a special significance in the philosophy of Immanuel Kant (1724-1804), who used it to describe the equally rational but contradictory results of applying to the universe of pure thought the categories or criteria of reason proper to the universe of sensible perception or experience (phenomena). [from wiki]

So something is going on here regarding the limits of logic. I think Kant is called a nominalist in most circles.


Peirce - Philosophy: Nominalism

For Kant the laws of logic were phenomenal. That is how he accounted for them.



Thanks! Kant's always confused me, but I thought most people today (Strawson and co) think Kant's work is best seen as analysis of our conceptual scheme rather than a transcendental deduction of categories.

Anyway, I thought the 'phenomenal world' was based on human minds, which again, Logical Absolutes are not the product of human minds, because human minds are different, not absolute.

---------- Post added 03-28-2010 at 02:49 AM ----------

I'm not too good with abstractions - ughaibu or Deckard - can you give me an example of this logic that does not use the law of contradiction?
I mean, how can you know a statement is true if it can't be false or contradicted !?

Thanks for the replies!
 
Deckard
 
Reply Sun 28 Mar, 2010 12:57 am
@spiltteeth,
spiltteeth;145076 wrote:

Anyway, I thought the 'phenomenal world' was based on human minds, which again, Logical Absolutes are not the product of human minds, because human minds are different, not absolute.

Aye, there's the rub. For Kant, the Laws of logic are not absolute or universal they are bracketed off with everything else knowable as phenomenal.

Hegel's dialectical logic was really developed as a way to resolve Kant's antinomies and grant us access to the noumenal.
Peirce calls Hegel "a nominalist of realistic yearnings." (Of course there are more than a few who do not consider Hegel's dialectical logic worthy of the name logic.) Hegel believed he had found the answer to the question you pose in the OP.

I think you will find Peirce's little tract on Nominalism worth reading. Peirce was a realist but he had a very deep understanding of it all and is very readable...and an American!!! USA! USA! USA!

Peirce - Philosophy: Nominalism

I am even less qualified to speak on Hegel than I am to speak on Kant but what I have said so far about the matter (I think) is accurate.

*Looks up Strawson*

---------- Post added 03-28-2010 at 02:06 AM ----------

spiltteeth;145076 wrote:


I'm not too good with abstractions - ughaibu or Deckard - can you give me an example of this logic that does not use the law of contradiction?
I mean, how can you know a statement is true if it can't be false or contradicted !?

Thanks for the replies!


I think Hegel's logic was an attempt to do this. Thesis and antithesis are contradictory but for Hegel the story does not stop there. Out of this contradiction a Synthesis arises.

Example

Thesis: Being
Antithesis: Nothing
Synthesis: Becoming

Yeah it's crazy sh*t but it's fun.
 
Pepijn Sweep
 
Reply Sun 28 Mar, 2010 02:25 am
@spiltteeth,
spiltteeth;145038 wrote:
How do nominalists account for the laws of logic?

[CENTER] I'm no expert, but it seems to me the laws of logic are universal; and they are certainly not material.
So if you don't believe in abstract objects how do you account for them?
[/COLOR][/SIZE]

Logic is Yust a word for a thinking-process. Has little to do with Logos. It's more a rational/science log-book becoming so anyway.

The basics are OK, but hardly sufficient for rapid progress.

I like Laws, I am LL.A myself according to my papers. But Laws change, some countries re-vise their Costutution / Natianal Identity

Myself I feel European. Less because my Nordic apearence but I love languages and now I hear English, American, Scottish and Roman languages in the Streets of my Town. It's different ; it's many Tourists, but they are well-come.

The End of Certainty made a big impression on me. Let me know if U need the Name of Author. I still have book even.

Kindness from Pep I,
Magisterdam
[/CENTER]
 
ughaibu
 
Reply Sun 28 Mar, 2010 03:36 am
@spiltteeth,
spiltteeth;145076 wrote:
I'm not too good with abstractions - ughaibu or Deckard - can you give me an example of this logic that does not use the law of contradiction?
I mean, how can you know a statement is true if it can't be false or contradicted !?
Here you go: Paraconsistent Logic (Stanford Encyclopedia of Philosophy)
 
spiltteeth
 
Reply Mon 29 Mar, 2010 12:13 am
@spiltteeth,
Well, thank you very much everybody.

Pretty much what I got out of Paraconsistency is that just because a statement is contradictory does not mean it is false, per se

Any who, the article still say
Quote:
smany paraconsistent logics validate the Law of Non-Contradiciton


So it still seems that the law of non-contradiction is still an absolute.

As far as Hegel....ack! He makes me dizzy!

I mean, what the hell is the antithesis of a cow?!

But, to use a real argument. If a guy says "listen, the bible is false because it contradicts itself and the law of contradiction is universal and absolute"

Would a nominalist then say "Maybe the bible IS false, but not for that reason because laws of logic can't be absolute, they depend on human minds which change, so maybe back then the prophets' laws of logic were such that statements could contradict each other and still be true"

In other words, I would say the statement "2+2=4 AND 2+2 does NOT=4" to be a false statement because it contradicts it self AND it always has and always will contradict itself because the law of non-contradiction is absolute and universal.

But a nominalist would say no, using Hegals laws of logic that statement CAN be true, so the law of non-contradiction isn't absolute.

The point I'm getting at is that IF the law of non-contradiction is absolute and universal then it CAN'T be material and hence nominalism CAN'T be true; I'm wondering how a nominalist would answer this - yr saying they would point to Hegel's laws of logic right?

Am I making any sense? :perplexed:
 
ughaibu
 
Reply Mon 29 Mar, 2010 12:55 am
@spiltteeth,
spiltteeth;145450 wrote:
So it still seems that the law of non-contradiction is still an absolute.
Then what do you suppose a true contradiction to be? Paraconsistent Logic (Stanford Encyclopedia of Philosophy)
You might also consider constructive mathematics, in which the law of excluded middle doesn't apply.
 
Deckard
 
Reply Mon 29 Mar, 2010 01:06 am
@spiltteeth,
spiltteeth;145450 wrote:
Well, thank you very much everybody.

Pretty much what I got out of Paraconsistency is that just because a statement is contradictory does not mean it is false, per se

Any who, the article still say

So it still seems that the law of non-contradiction is still an absolute.

As far as Hegel....ack! He makes me dizzy!

I mean, what the hell is the antithesis of a cow?!

But, to use a real argument. If a guy says "listen, the bible is false because it contradicts itself and the law of contradiction is universal and absolute"

Would a nominalist then say "Maybe the bible IS false, but not for that reason because laws of logic can't be absolute, they depend on human minds which change, so maybe back then the prophets' laws of logic were such that statements could contradict each other and still be true"

In other words, I would say the statement "2+2=4 AND 2+2 does NOT=4" to be a false statement because it contradicts it self AND it always has and always will contradict itself because the law of non-contradiction is absolute and universal.

But a nominalist would say no, using Hegals laws of logic that statement CAN be true, so the law of non-contradiction isn't absolute.

The point I'm getting at is that IF the law of non-contradiction is absolute and universal then it CAN'T be material and hence nominalism CAN'T be true; I'm wondering how a nominalist would answer this - yr saying they would point to Hegel's laws of logic right?

Am I making any sense? :perplexed:


Please allow me to think out loud about this matter.

I don't know enough to say but I think maybe we take a step back rather than using particular examples. The primary Thesis Antithesis Synthesis is Being, Nothing and Becoming.

Rather than look to particulars we could say that the thesis is the law of contradiction is universal and absolute and the antithesis is that this law does not hold in all cases. Hegel's logic proceeds through the negation of the negation but since Hegel's system is dynamic and evolutionary this negation of the negation does not return to the original thesis. There is some B that is neither A nor not A that sort of grows out of the conflict between A and not A and comes closer to reality than both. Some paradigm shift perhaps that causes one to see both A and not A in a new light. Not right nor left but up or something of that sort. A new dimension is added. In the primary case A = Being which brings with it not A = non-being or nothing...at which point the new dimension is added namely, time in this case and we have B = becoming. Ever expanding and revealing more dimensions of thought.

I am completely out of my depth here but I also want to mention Descartes cogito as a possible starting point of Being. I think therefor I am. There are things that I am not. There are things which I am becoming. It is important to consider the starting point. Can we really begin by stating an abstract law such as A and not A cannot both be true. If we remember Descartes method which arguably kicked off modern philosophy such a law could be proposed by some demon but Descartes meditations strip all of this away and the primary existing A is the I, the thinking I, ever grounded in subjective experience. The attempt to cut the assertion of A completely away from this subjective experience is to not start at the beginning, to not be certain. And I think Hegel, Kant even Hume and Locke all begin from Descartes cogito as the first true assertion, the first A... "I am" and so "I am not that" and so "I am becoming".

There is no Platonic realm of real things to resort to and that is what makes Hegel and Kant nominalists. The real beginning is inside, subjective not outside and objective.

There is something after Becoming...It might be passing away...or memory... I have to look it up in a book somewhere...It's surprisingly hard to find online...but I think there is a specific order through several movements through which the primary Being of Consciousness (which I have equated with Descartes cogito) passes through...as dimensions are added to consciousness. It seems to proceed through an adding of axises. We have the X axis establishes the spectrum from Being to Non-Being then add the Y axis which establsishes Becoming and Passing Away and then a Z axis and so on ad infinitum.

But in conclusion, I believe it is of primary importance to recognize from what point a given philosopher begins to philosophize, that is, begins to Reason. For Kant, Hegel and the German nominalist idealist I believe the point is Descartes cogito...the one sure thing.

Others begin with the one sure thing of A and not A cannot both be true.

In the course of his famous meditation, Descartes even dismissed mathematical truths as uncertain and possibly the work of the evil deceiving demon. So I think for Descartes the statement A and not A cannot both be true is equally dismissible.
 
spiltteeth
 
Reply Mon 29 Mar, 2010 01:07 am
@ughaibu,
ughaibu;145455 wrote:
Then what do you suppose a true contradiction to be? Paraconsistent Logic (Stanford Encyclopedia of Philosophy)
You might also consider constructive mathematics, in which the law of excluded middle doesn't apply.


Yea, the thing I quoted was from that article -
Quote:


As I say, just because a sentence is contradictory, according to paraconsistant logic, doesn't mean its false, per se.

It gives the example of the liar paradox: 'This sentence is not true'

But paraconsistant logic still upholds most of the laws of contradiction, for instance, it would hold up to my example : the sentence "it is true 2+2=4 AND that 2+2 does not =4"

In other words, paraconsistant logic doesn't mean the law of contradiction isn't absolute, just that to be absolute it has to be contradictory AND logically paraconsistant.

Well, that's fine. So a sentence that is contradictory AND paraconsistant is ALWAYS false and always will be, such as in my example.
This is a logical absolute.

So, to repeat my original point, Logical absolutes are conceptual by nature, but I don't see how they are dependent on space, time, physical properties, or human nature etc
They are not the product of the physical universe (space, time, matter), because if the physical universe were to disappear, logical absolutes would still be true.
Logical Absolutes are not the product of human minds, because human minds are different, not absolute.
But, since logical absolutes are always true everywhere, and not dependent upon human minds, they must be an abstract nonmaterial object.

So how does a nominalist account for this?

---------- Post added 03-29-2010 at 03:21 AM ----------

Deckard;145459 wrote:
Please allow me to think out loud about this matter.

I don't know enough to say but I think maybe we take a step back rather than using particular examples. The primary Thesis Antithesis Synthesis is Being, Nothing and Becoming.

Rather than look to particulars we could say that the thesis is the law of contradiction is universal and absolute and the antithesis is that this law does not hold in all cases. Hegel's logic proceeds through the negation of the negation but since Hegel's system is dynamic and evolutionary this negation of the negation does not return to the original thesis. There is some B that is neither A nor not A that sort of grows out of the conflict between A and not A and comes closer to reality than both. Some paradigm shift perhaps that causes one to see both A and not A in a new light. Not right nor left but up or something of that sort. A new dimension is added. In the primary case A = Being which brings with it not A = non-being or nothing...at which point the new dimension is added namely, time in this case and we have B = becoming. Ever expanding and revealing more dimensions of thought.

I am completely out of my depth here but I also want to mention Descartes cogito as a possible starting point of Being. I think therefor I am. There are things that I am not. There are things which I am becoming. It is important to consider the starting point. Can we really begin by stating an abstract law such as A and not A cannot both be true. If we remember Descartes method which arguably kicked off modern philosophy such a law could be proposed by some demon but Descartes meditations strip all of this away and the primary existing A is the I the thinking I ever grounded in subjective experience. The attempt to cut the assertion of A completely away from this subjective experience is to not start at the beginning. And I think Hegel, Kant even Hume and Locke all begin from Descartes cogito as the first true assertion, the first A... "I am" and so "I am not" and so "I am becoming".

There is no Platonic realm of real things to resort to and that is what makes Hegel and Kant nominalists. The real beginning is inside, subjective not outside and objective.

There is something after Becoming...It might be passing away...or memory... I have to look it up in a book somewhere...It's surprisingly hard to find online...but I think there is a specific order through several movements through which the primary Being of Consciousness (which I have equated with Descartes cogito) passes through...as dimensions are added to consciousness. It seems to proceed through an adding of axises. We have the X axis establishes the spectrum from Being to Non-Being then add the Y axis which establsishes Becoming and Passing Away and then a Z axis and so on ad infitum.

But in conclusion I believe it is of primary importance to recognize from what point a given philosopher begins to philosophize that is begins to Reason. For Kant, Hegel and the German nominalist idealist I believe the point is Descartes cogito...the one sure thing.

Others begin with the one sure thing of A and not A cannot both be true.

Descartes even dismissed mathematical truths as uncertain and possibly the work of the evil deceiving demon. So I think for Descartes the statement A and not A cannot both be true is equally dismissible.



SO, if Decarte is saying the Law of noncontradiction is "dismissible" then one can never say whether a statement is true or false.

For example the statement " A and not A cannot both be true is equally dismissible." can never be proven true or false, therefore we cannot believe it to be true.

In other words, yr whole paragraph can never be true. No statement can, including "no statement can ever be true"

So nothing anyone says can be intelligible.

So the statement "Nominalism is true" can never be true...

Does anyone know of any person who has tried to live without the law of noncontradiction?

I remember an old logic teacher once say "everytime you choose to walk through a door instead of a wall, you are affirming the law of non-contradiction" :bigsmile:

---------- Post added 03-29-2010 at 03:27 AM ----------

Oh, and for Decarte's argument to be sound, it would have to go :

1) Everything that thinks exists
2) I think
3) Therefore I exist

Otherwise the conclusion does not necessarily follow from the 2 premises.
But if yr saying Decarte dismissed the laws of logic as true then obviously they can't be used to prove anything true!
 
Deckard
 
Reply Mon 29 Mar, 2010 01:51 am
@spiltteeth,
spiltteeth;145460 wrote:


SO, if Decarte is saying the Law of noncontradiction is "dismissible" then one can never say whether a statement is true or false.

For example the statement " A and not A cannot both be true is equally dismissible." can never be proven true or false, therefore we cannot believe it to be true.

In other words, yr whole paragraph can never be true. No statement can, including "no statement can ever be true"

So nothing anyone says can be intelligible.

So the statement "Nominalism is true" can never be true...

Does anyone know of any person who has tried to live without the law of noncontradiction?

I remember an old logic teacher once say "everytime you choose to walk through a door instead of a wall, you are affirming the law of non-contradiction" :bigsmile:


It is important to remember that Descartes meditation is a project of radical skepticism. After establishing certainty of his own existence Descartes then finds his way to the certainty of God's existence and then the truth of laws like A and not A cannot both be true. Kant took a different second step and did not feel the need to establish the existence of God but rather he bracketed* off all experience as phenomenal and conditioned by the subjective mind. For Kant, the law "A and not A cannot both be true" is something the subjective mind brings with it, something that is impossible to escape and yet nevertheless phenomenal. So for Kant it is a difference between saying "it is impossible to think otherwise" and "it is absolutely true".

"Nominalism is true" and "A and not A cannot both be true" are both true statements but only insofar and only because this is the way our subjective minds structure and condition reality. They can never be true in the universal and absolute sense without this phenomenological caveat. For Kant, these statements are not necessarily true (though it may be) outside of phenomenal experience.

I'm not sure why Peirce said that Kant's philosophy would have been more straightforward had he been a realist.

As I am writing this I am wondering that there must be a profound connection between the subjective/objective and nominalism/realism. Starting from the subjective truth of the cogito one has the opportunity to be a nominalist. Starting from A and not A cannot both be true one can only be a realist. It is almost as if the one reduces to the other. Again it is a matter of where one begins to philosophize. Descartes radical skepticism or some other alternative such as Plato's or Aristotle's.


*The term "bracketing" I think traces back to Husserl so I am a little worried that I am conflating Kant with Husserl but the term seems to fit.
 
 

 
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