Democratic Underground Latest Greatest Lobby Journals Search Options Help Login
Google

Is logic ignorant?

Printer-friendly format Printer-friendly format
Printer-friendly format Email this thread to a friend
Printer-friendly format Bookmark this thread
This topic is archived.
Home » Discuss » Topic Forums » Science Donate to DU
 
Boojatta Donating Member (1000+ posts) Send PM | Profile | Ignore Fri May-01-09 04:07 PM
Original message
Poll question: Is logic ignorant?
Edited on Fri May-01-09 04:11 PM by Boojatta
Logic: To speak of an axiom as being "true" is to reveal ignorance.

Boojatta: Do you agree that if there exists even one instance of a rule of inference that involves an assumption that is true and a conclusion that is false, then that rule of inference is faulty?

Logic: Yes, of course. You can rely on me.

Boojatta: Is it possible for an instance of a rule of inference to involve an assumption that is an axiom of standard mathematics?"

Logic: Yes, of course. Otherwise, the axioms of standard mathematics would be cut off from everything else. You would be unable to use the axioms to prove any theorems.

Boojatta: Okay, let's put that together now, shall we? Suppose that there exists at least one instance of a rule of inference that involves a true assumption that is an axiom of standard mathematics and that involves a false conclusion. Is such a rule of inference faulty?

Logic: Yes, so what?

Boojatta: "Yes" isn't good enough. Please say it as your own utterance. I, Logic, do solemnly believe...

Logic: Very well, but as a Quaker I refuse to take the oath. Suppose that there exists at least one instance of a rule of inference that involves a true assumption that is an axiom and that involves a false conclusion. Then that particular rule of inference is faulty.

Boojatta: Are you just saying that to be agreeable?

Logic: No, I meant it.

Boojatta: You spoke of an axiom as being true. You have revealed your ignorance.
Printer Friendly | Permalink |  | Top
BlooInBloo Donating Member (1000+ posts) Send PM | Profile | Ignore Fri May-01-09 04:11 PM
Response to Original message
1. Sigh.
Printer Friendly | Permalink |  | Top
 
On the Road Donating Member (1000+ posts) Send PM | Profile | Ignore Fri May-01-09 04:24 PM
Response to Original message
2. Logic is Never Reliable
because terms can never be defined and applied consistently to future possibilities.

Induction is the opposite of logic, and is faulty, but has a better track record.

In the sphere of political discourse, those who consistenly bring up what "logic would dictate" tend to be conservative populists without a whole lot of experience beyond their neighborhood.

Printer Friendly | Permalink |  | Top
 
xchrom Donating Member (1000+ posts) Send PM | Profile | Ignore Fri May-01-09 05:47 PM
Response to Reply #2
3. can't logic be informed by fact and science?
you sound more like you're describing common sense than logic.
Printer Friendly | Permalink |  | Top
 
TreasonousBastard Donating Member (1000+ posts) Send PM | Profile | Ignore Fri May-01-09 11:57 PM
Response to Original message
4. Of course logic is ignorant-- it is...
merely a tool and has no more knowledge or wisdom than a hammer or computer. It does precisely what it is instructed to do and any "knowledge" or "truth" is external to it.

(Being slick with the definition of "axiom" doesn't change that one bit.)


Treasonous the Logician



Printer Friendly | Permalink |  | Top
 
Boojatta Donating Member (1000+ posts) Send PM | Profile | Ignore Sat May-02-09 09:16 AM
Response to Reply #4
5. I agree with you.
Edited on Sat May-02-09 09:31 AM by Boojatta
Somebody can accuse a fellow message board participant of "ignorance" and chalk that up as one point won by the side of the debate from which the ad hominem attack originated. A similar attack against logic unfortunately doesn't even make sense. Perhaps I should have capitalized the word "logic" in the title of this thread to identify it with the personification of logic named "Logic" who has a role in the Original Post of this thread.

The Original Post is designed to display not a potential problem with logic, but a potential problem with the opening statement in the dialog ("To speak of an axiom as being 'true' is to reveal ignorance"). However, staunch advocates of the opening statement in the dialog are predisposed to think of the opening statement as an unquestionable principle of logic. It is their logic and not logic itself that is the target of gentle mockery.
Printer Friendly | Permalink |  | Top
 
Boojatta Donating Member (1000+ posts) Send PM | Profile | Ignore Sun May-17-09 06:40 PM
Response to Original message
6. Kick
Printer Friendly | Permalink |  | Top
 
Boojatta Donating Member (1000+ posts) Send PM | Profile | Ignore Wed Jul-01-09 10:18 PM
Response to Original message
7. Kick
Printer Friendly | Permalink |  | Top
 
Salviati Donating Member (1000+ posts) Send PM | Profile | Ignore Thu Jul-02-09 11:34 AM
Response to Original message
8. Any interesting logical system is either incomplete or inconsistant...
Edited on Thu Jul-02-09 11:36 AM by Salviati
http://en.wikipedia.org/wiki/G%C3%B6del's_incompleteness_theorems


Either there exist true statements that cannot be proven from the axioms as given, or if every true statement can be proven, then the axioms will invariably also show that some false statements are also true.
Printer Friendly | Permalink |  | Top
 
Boojatta Donating Member (1000+ posts) Send PM | Profile | Ignore Thu Jul-02-09 10:57 PM
Response to Reply #8
9. Are you simply indicating that you aren't interested in first-order logic?
I presume that you are aware that Kurt Gödel proved the completeness of first-order logic in 1929, which was before he proved the incompleteness of any recursively enumerable axiomatization of number theory.

If you examine the Original Post carefully, you should observe that it deals with matters that are much more general than number theory.

Consider an analogy. There is a concept of the "boundary" of any subset of a topological space. There's also a concept of a "boundary" of a manifold in an ordinary, finite-dimension Euclidean space. However, until you invent some concept of the "boundary" of an arbitrary set, the word "boundary" has no meaning in that general context.

Similarly, until you can define the concepts of formal number theory using just the resources available in the dialog of the Original Post, you aren't in a position to invoke Gödel's incompleteness theorem in an attempt to resolve the problem posed by the Original Post. Of course, there's no problem to be resolved if you don't insist that it's meaningless to speak of an axiom as being true.
Printer Friendly | Permalink |  | Top
 
Boojatta Donating Member (1000+ posts) Send PM | Profile | Ignore Thu Aug-13-09 10:02 PM
Response to Original message
10. Kick
Printer Friendly | Permalink |  | Top
 
Boojatta Donating Member (1000+ posts) Send PM | Profile | Ignore Thu Sep-10-09 02:07 PM
Response to Original message
11. Kick
Printer Friendly | Permalink |  | Top
 
pfloydguy7750 Donating Member (50 posts) Send PM | Profile | Ignore Fri Sep-11-09 02:05 AM
Response to Original message
12. no. stupid question
Printer Friendly | Permalink |  | Top
 
Boojatta Donating Member (1000+ posts) Send PM | Profile | Ignore Fri Sep-11-09 10:42 AM
Response to Reply #12
13. Welcome to Democratic Underground, pfloydguy7750.
Edited on Fri Sep-11-09 10:56 AM by Boojatta
Could you share with readers of this thread any information about the criteria that you use? I mean the criteria that you use to decide whether a question is correctly classified as "stupid" or correctly classified as not necessarily "stupid".

Note: I formulated things above using the term "correctly classified" because you expressed your judgment without making any explicit reference to yourself. Imagine that you had written something like the following: "I, pfloydguy7750, have contemplated the question and it wasn't thought-provoking, and the asking of the question violates some principle of clearness and simplicity that I personally respect and adhere to." In that case, you would have carried some load in the conversation. In a sense, you would be meeting me half-way, and making it easy for me or anyone else interested in this thread to respond to you.

After all, if a question can be stupid, then why can't the personification of logic identified in the dialog as Logic be ignorant?
Printer Friendly | Permalink |  | Top
 
Boojatta Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Sep-27-09 11:01 AM
Response to Original message
14. Kick
Printer Friendly | Permalink |  | Top
 
bananas Donating Member (1000+ posts) Send PM | Profile | Ignore Mon Sep-28-09 11:30 PM
Response to Reply #14
15. For you
Printer Friendly | Permalink |  | Top
 
Boojatta Donating Member (1000+ posts) Send PM | Profile | Ignore Sat Nov-07-09 01:49 PM
Response to Original message
16. Kick
Printer Friendly | Permalink |  | Top
 
Boojatta Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Dec-27-09 12:34 AM
Response to Original message
17. Kick
Printer Friendly | Permalink |  | Top
 
Fumesucker Donating Member (1000+ posts) Send PM | Profile | Ignore Sun Dec-27-09 11:20 PM
Response to Original message
18. If Boojatta was a drug...
How might one go about ingesting this delightful substance?
Printer Friendly | Permalink |  | Top
 
DU AdBot (1000+ posts) Click to send private message to this author Click to view 
this author's profile Click to add 
this author to your buddy list Click to add 
this author to your Ignore list Tue Apr 30th 2024, 09:31 AM
Response to Original message
Advertisements [?]
 Top

Home » Discuss » Topic Forums » Science Donate to DU

Powered by DCForum+ Version 1.1 Copyright 1997-2002 DCScripts.com
Software has been extensively modified by the DU administrators


Important Notices: By participating on this discussion board, visitors agree to abide by the rules outlined on our Rules page. Messages posted on the Democratic Underground Discussion Forums are the opinions of the individuals who post them, and do not necessarily represent the opinions of Democratic Underground, LLC.

Home  |  Discussion Forums  |  Journals |  Store  |  Donate

About DU  |  Contact Us  |  Privacy Policy

Got a message for Democratic Underground? Click here to send us a message.

© 2001 - 2011 Democratic Underground, LLC