Talk:Mathematical proof

Euclid and Indirect Proof

First, many apologies. I know I typed something like this when I made a small change a few days ago. Somehow it did not remain so I am typing this first. I have no interest in a reversion conflict. Just wanted to make a change and state the reason. The change is to return a few sentences relating to "the first proof by contradiction" I have no opinion about the value one way or the other about these few sentences. My problem is that they were removed with the total justification being something like "Euclid's proof of the infinitude of primes was the first proof by contradiction" (not a direct quote.) As Wikipedia itself correctly says (Euclid's Proof) "Euclid is often erroneously reported to have proved this result by contradiction" (and other parts of Wikipedia do say that) That is based on the following common misconception that Euclid book IX prop 20 says something like

Prop: There are infinitely many primes

1. Suppose that there were finitely many and list them p1,p2,..pk

2. Use the list to create the number P=p1*p2*...*pk+1

3. There is a prime q dividing P (maybe q=P) and it is not in the list CONTRADICTION

It is true that the proof is nowadays often presented this way and that there are claims (including some parts of Wikipedia) that this is essentially what Euclid wrote. However what was actually written was more like, there are always more primes (than in any finite list)

Prop: No finite list of primes includes all primes

1. Given a list p1,p2,..pk (here is how to get something else)

2. Use the list to create the number P=(p1*p2*...*pk)+1

3. There is a prime q dividing P (maybe q=P) and it is not in the list (there, something else)

SO I am happy with some other reason to remove the claim I reverted, but not the given one. Gentlemath (talk) 02:31, 16 February 2015 (UTC)

Induction and Deduction as methods of inference

Inductive inference and deductive inference are both regularly used in mathematical proof.

The article "Mathematical induction" declares the method of mathematical induction as deductive inference, but, it's inductive inference.

It neither clear nor unambiguous (nor non-controversial) to call "inductive inference" (exhaustive inductive inference, as of proof by induction) instead "deductive inference", because it's not.

It is clear and unambiguous that "exhaustive" deductive or inductive inference (i.e., covering all cases) does maintain derivability of conclusion from premise and otherwise maintains the grounds for mathematical proof.

It is very widely understood that "proof by induction" is "mathematical proof by mathematical induction" in any context of mathematical proof. — Preceding unsigned comment added by 75.172.122.39 (talk) 07:10, 18 March 2017 (UTC)

This has that the disambiguation of mathematical inductive inference and the inference of reasonable expectations would go into the article on induction, to leave clearly in the main article of mathematical proof the deductive and mainly inductive inferential arguments as relevant to the derivability via inference of conclusion from premise. "Induction inference of expectations" ("common sense") should be disambiguated from exhaustive "inductive inference by cases" (mathematical induction), instead of overloading the definition of deductive inference (the contrapositive, that syllogism is the inductive).

This involves a rather significant difference in definitions of overloaded primary terms.

External links modified

Hello fellow Wikipedians,

I have just modified one external link on Mathematical proof. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:

• Added archive https://web.archive.org/web/20090215114618/http://home.att.net/~fractalia/history.htm to http://home.att.net/~fractalia/history.htm

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

This message was posted before February 2018. After February 2018, "External links modified" talk page sections are no longer generated or monitored by InternetArchiveBot. No special action is required regarding these talk page notices, other than regular verification using the archive tool instructions below. Editors have permission to delete these "External links modified" talk page sections if they want to de-clutter talk pages, but see the RfC before doing mass systematic removals. This message is updated dynamically through the template {{source check}} (last update: 5 June 2024).

• If you have discovered URLs which were erroneously considered dead by the bot, you can report them with this tool.
• If you found an error with any archives or the URLs themselves, you can fix them with this tool.

Cheers.—InternetArchiveBot (Report bug) 23:51, 12 June 2017 (UTC)

"Story Proof" section needed?

From basic mathematical study I have come across the notion of story proofs. Some are used in a book I am reading (Introduction to Probability by Blitzstein and Hwang). It seems like its own category of proof, so perhaps a section should be added here, or a new Wikipedia page created. I would do it, but I'm not confident enough in my mathematical knowledge to consider editing this page. So I figured I would provide a suggestion instead. Proxyma (talk) 23:44, 28 June 2017 (UTC)

I think as a minimum there would have to be references that showed the term "story proof" has a clear, widely understood meaning in the mathematical community, outside of this one text book. I did a quick Google search, but the only links I could see refer to a book "Story Proof: The Science Behind the Startling Power of Story" by Kendall F. Haven, which has nothing to do with mathematical proof. Gandalf61 (talk) 08:52, 29 June 2017 (UTC)

Here at https://books.google.com/books?id=EvoYCwAAQBAJ&pg=PA19 there's some rather nice examples (and more in the book), but if indeed this is the only book where it is mentioned, I don't think we should have it in our article—just per wp:primary source and wp:undue. - DVdm (talk) 12:33, 29 June 2017 (UTC)

And I think the standard term for the type of proof described in that link is double counting. Gandalf61 (talk) 15:49, 29 June 2017 (UTC)

I agree that it is odd that Google doesn't turn up much. My impression was that "story proof" specifically referred to the English text accompanying the equation, and that the author basically meant "proving by providing an interpretation."

Here is how it is described in the book: A story proof is a proof by interpretation. For counting problems, this often means counting the same thing in two different ways, rather than doing tedious algebra. A story proof often avoids messy calculations and goes further than an algebraic proof toward explaining why the result is true. The word “story” has several meanings, some more mathematical than others, but a story proof (in the sense in which we’re using the term) is a fully valid mathematical proof.

I am not super experienced in math, but I have definitely seen plenty of accompanying text to equations. I think story proof is the author's attempt to give that a name. I admit, though, that there's a significant overlap with double counting techniques in the story proofs I've seen so far. Proxyma (talk) 00:14, 30 June 2017 (UTC)

The redirection of the methods of proof here is biased, it promotes logical monism but we don't even have the page of it

Not all methods of proof are mathematical.

see: law

This biased redirection causes problems to other pages.

I love mathematics, but it's unmathematical to force mathematics as self-caused without using the foundations of mathematics according to which mathematics isn't absolute and self-caused = logical monism is wrong.

see: logical pluralism (experimental logical foundations, not necessarily useful)