Talk:Reductio ad absurdum/Archive 1

Archive 1

Merge with Proof by contradiction?

Discuss. --128.62.37.246 (talk) 01:22, 19 January 2010 (UTC)

Reductio de absurdum?

One night while watching the Colbert Report, Colbert made a comment for comedic effect that seems to hold logical water, and I was wondering if there have been any formal definitions of such an argument. He and his guest were discussing child labor in China. The guest was saying that forced child labor is morally wrong and should not be tolerated. Colbert compared this to parents forcing their children to do chores around the house, saying that it is essentially the same thing but most would not claim it to be morally wrong. This specific example is not necessarily a good argument; while it does disprove the assertion as stated (that any child labor is intolerable), it is attacking a strawman in the process of fighting the intended assertion that forced child labor of this extreme is intolerable. However, the idea behind the debate tactic is sound: one can disprove certain arguments by applying their premise to another situation which yields a less absurd result. Is there any documented acknowledgement of this sort of argument? If so, what is it called? Should it be included in this article as the opposite of the common reductio ad absurdum? --Daniel Draco (talk) 17:22, 25 December 2009 (UTC)

Daniel, in my opinion that would be a classic use of the straw man fallacy. Basically it's where you modify a line of argument in a way that is ridiculous and then show how ridiculous your modified argument is, and from that conclude that the original argument is ridiculous. I couldn't think of any good examples, but the name is pretty self-explanatory: rather than attacking your target, you make a weak imitation stuffed with straw, and you attack your imitation. 203.217.150.69 (talk) 00:43, 1 February 2010 (UTC)

The Definition and the description of "Proof by Contradiction"

The first paragraph and the second paragraph were nearly redundant; and the first paragraph was not satisfactory, since it did not describe a genus of the 'particular kind of RAA' that is detailed in the second paragraph, but rather described a vaguer wording of the same. I adjusted the definition, but in the process made it nearly identical to the second paragraph.

I thence undid my modification and made a minor edit to the definition, changing "implications to a logical but absurd consequence" to "implications logically to an absurd consequence" in order to emphasize that the process of arriving at the conclusion is logical and not emphasize that the conclusion itself is logical (though it is). This is because, to the layman, the adjective 'logical' has implications of truth value while in the field of Logic, it has no such connotation since a conclusion can be logically derived from a false premise.

I also made a nonminor modification to the second paragraph, since it is not entirely accurate. Proof by contradiction refers specifically to the proof of a proposition by proving that it is impossible for it to be false, therefore it is true.

Thus I have corrected the redundancy.

As is stated in the first cited text, Reductio ad Absurdum is not the same as Proof by Contradiction but is rather a genus of Proof by Contradiction. My amendment to the first two paragraphs should serve to make that distinction clear.

I have also added a Pop Culture section to refer to the episode of the Big Bang Theory wherein Sheldon misuses and misdefines Reductio Ad AbsurdumSpezied (talk) 07:45, 7 July 2010 (UTC)

The Addition of a New Example

A more substantial, logical, clear, nonspeculative, and especially unoriginal example was needed than the current one. I have added a prop from Euclid, his elements being a fine source of Reductio arguments. I was sure to pick a prop that did not build too greatly on other props so that a reader unacquainted with the work would not be confused. I also did not fully describe the prop for simplicity sake, leaving out the construction and the process of deducing the inequality of the radii.

An illustration for the Prop would be nice, but I do not know of any royalty-free illustration.

I did not think it appropriate to completely remove the former example after the addition of my own, since it touches on other topics that mine does not. But the section does need improvement.

If the example of Ad Coelum needs explanation that it is also a strawman fallacy, then a new example is needed since explaining the flaws of an example destroys the clarity of the example. An example should be immediately patent if possible.Spezied (talk) 16:10, 7 July 2010 (UTC)

Addition of a simpler example

The examples currently on the page are somewhat confusing. The Neils Bohr example assumes that the idea that "the opposite of every great idea is another great idea" is in itself a great idea, which leads to reductio ad absurdum, but it isn't really clear why it's assumed that Neils Bohr's statement is a great idea, and even if there is valid reasoning behind that assumption, examples should be clear, and free of the need for background explanation of assumptions.

The ad coelum example seems to be one specifically addressing the legal use of reductio ad absurdum, so while I find it confusing, its presence makes more sense.

I added a more intuitive, plainer example of a reductio ad absurdum. While I would like to take out the Bohr example, I will leave that decision in the hands of others.125.54.141.237 (talk) 03:59, 3 February 2011 (UTC)

I decided to clean up the ad coelum example, which was written quite confusingly. However, in doing so, once I finally figured out what it was actually saying, I realized that it wasn't an example of where legal use of reductio ad absurdum differs from conventional use, but an example of where reductio ad absurdum can be used (in both legal and conventional senses) on the literal meaning of ad coelum, but not (in either a legal or conventional sense) on the legal meaning of ad coelum. This would be a great example to put on the ad coelum page, but it has nothing to do with reductio ad absurdum itself.

Specifically, the example said that:

1) Literally, reductio ad absurdum can only be used to argue against self-contradiction.

2) In legal and everyday use, though, it is used to argue against things which are merely undesirable.

3) It presented the concept of ad coelum, saying that used literally, it would imply that people, by buying a plot of land, would own everything which fell in a cone from the center of the earth to infinitely deep in space, including all the planets.

4) Both legally and in an everyday sense, that is undesirable, so you could use the non-literal sense of reductio ad absurdum against it.

5) But that's not what ad coelum legally means.

6) Ad coelum, legally, only extends as high as is necessary to reasonably enjoy ones land.

7) Therefore, you can't use reductio ad absurdum, legally or in the everyday sense, on the legal usage of ad coelum.

Again, that's great, and interesting, but it sheds no light on reductio ad absurdum, nor on how its legally used, nor on whether its legal usage varies from the everday usage. It just educates people about the difference between the everyday definition of ad coelum, and the legal definition of ad coelum.

The only important point that it even brought up was that literally reductio ad absurdum can only be applied when propositions result in self-contradiction, but that legally and in everyday use it can also be applied when propositions result in "absurd" conclusions. If anyone can find some citations for this, and make a clear section which explains the difference between the literal and conventional/legal meanings of 'reductio ad absurdum', it would be appreciated. 125.54.141.237 (talk) 04:41, 3 February 2011 (UTC)

"The opposite of every great idea is another great idea."

This statement made by Niels Bohr has been used as an example here but does a great idea have to be true? Take the case of reductio ad absurdum itself. We use it to prove an assumption wrong but that doesn't mean that the assumption isn't important as it can facilitate better understanding of something.Krisinboots (talk) 09:26, 20 May 2010 (UTC)

• I know what you mean, it just has to be taken cynically. The grammar police won't come take you away if you mistakenly label something great :) It's a subjective contingency to claim that great ideas are true ideas, so this argument is not true for all instances in time and space, though it is for some. —Preceding unsigned comment added by 67.221.84.189 (talk) 00:44, 4 April 2011 (UTC)

Niels Bohr Example Removed

The following example was removed, because it represents several fallacies committed by Sagan (grrrr), who clearly wished to misrepresent Bohr's unorthodox comments. The "opposite" does NOT mean a logical dichotomy where a great idea is or is not, or that only two discrete ideas exist in a logical set. The dichotomy is Sagan's deliberate strawman to create an easy target for his reductio.

What Bohr means is analogous to saying that "the opposite of heads is tails" for a coin. A great idea is entailed by appropriate premises which also (sometimes) generate a converse of equal greatness.

"Another example concerns the following statement, attributed to physicist Niels Bohr: "The opposite of every great idea is another great idea." Carl Sagan used a reductio ad absurdum argument to counter this claim. If this statement is true, he argued, then it would certainly qualify as a great idea - it would automatically lead to a corresponding great idea for every great idea already in existence. But if the statement itself is a great idea, its opposite ("It is not true that the opposite of every great idea is another great idea", provided "opposite" is a synonym of "negation" in Bohr's aphorism) must also be a great idea. The original statement is disproven because it leads to an absurd conclusion: that an idea can be great regardless of whether it is true or false.

BlueMist (talk) 19:50, 18 October 2011 (UTC)

References

Ontological argument

A new user removed the following section for being a "subjective and incorrect insult". The source given seems fairly legit, and in my opinion the idea that it's an insult is very POV. I'm not sure it adds anything to the article though, so I've not reverted it to see if anyone has an opinion either way first.

"The ontological argument for the existence of God, as it was originally stated by Anselm of Canterbury, is an example of an attempted reductio ad absurdum."

BulbaThor (talk) 20:02, 3 April 2012 (UTC)

It seem to me, that the user's comment is uninformed and biased. He doesn't seem to like the point of the argument. The Ontological Argument is a famous and important deductive reductio. Whether it succeeds is controversial, so, the argument's mention adds much to the article's reader appeal. I'd hate to lose it. However, it is also so convoluted in detail that it may not be the ideal encyclopedic example. http://plato.stanford.edu/entries/ontological-arguments/ or http://www.princeton.edu/~grosen/puc/phi203/ontological.html

BlueMist (talk) 02:00, 5 April 2012 (UTC)

Poor example

The argument against the "raising taxes raises tax revenue" proposition is rather poor. It contains this claim: "If taxes were raised to 100% of income, individuals would not work". This is a synthetic claim, and does not follow purely from logical reasoning. (Also, the implied factual claim is false, as there have existed social systems where individuals (e.g. slaves) received no monetary income but worked anyway for other reasons.) The second example is better because the claim "If taxes were lowered to 0%, no taxes at all would be collected" is true by the definition of terms and does not rely on any hypotheses about human behavior. Can someone modify the first example so that it does not rely on presumed facts? If this proves impossible, I suggest it be removed. Augurar (talk) 04:36, 13 June 2012 (UTC)

Actually raising taxes to 100% of income is a perfect reductio ad absurdum argument. None of the examples listed are actually reductio ad absurdum arguments because there's nothing absurd being done. You have to take the thing to absurd proportions to demonstrate how the restrained (in comparison to your absurd measures) measures being advocated are false. Also the effects must be related between the restrained use and the total or absolute (absurd) use. — Preceding unsigned comment added by 173.238.208.230 (talk) 18:45, 18 February 2013 (UTC)

This article is incomplete. Reductio ad absurdum refers not only to the logical fallacy but also to the concept that a statement can be shown to be false if its truth would lead to a false or contradictory statement being accepted as true. See http://www.iep.utm.edu/reductio/ the Internet Encyclopedia of Philosophy by Nicholas Rescher and http://en.wikipedia.org/wiki/Proof_by_contradiction the wiki article referencing reductio ad absurdum as a more general case of proof by contradiction. 20 June 2012 — Preceding unsigned comment added by 69.209.201.216 (talk) 03:19, 21 June 2012 (UTC)

Yeah, I thought I remembered reading that "reductio ad absurdum" wasn't a logical fallacy, but just a method of demonstrating that an argument is false because you take it to a logical conclusion that is terrible/absurd. We've only one link here and it doesn't look that great. Hm... Byelf2007 (talk) 03:33, 21 June 2012 (UTC)

Better example

We seriously can't get a better example than the current one? I don't think a logical fallacy is a helpful example for people trying to understand the concept. It's hard to come up with a good example, but it might be better to use a claim that's patently absurd on its face, instead of a straw man of a legitimate argument. Ideally, of course, what we'd need is an example of the technique used in a real debate--only problem there is that we have an issue with neutrality, as some might argue, if its a topical issue, that the reductio argument is faulty, etc.

Here's a good example of argumentum ad absurdum. Smoking is bad for you. If it's not, try smoking fifty cigarettes a day, or a hundred or two hundred. can you imagine the consequences? You'd be coughing up stuff constantly and would probably get cancer very quickly. — Preceding unsigned comment added by 173.238.208.230 (talk) 18:48, 18 February 2013 (UTC)

In any case though, I think the one that stands isn't terribly helpful. —Preceding unsigned comment added by 99.255.195.165 (talk) 20:01, 20 April 2010 (UTC)

The current example regarding ad coelum is a mess, and the "great ideas" example is questionable. I find that beyond the first paragraph, the rest of the article just serves to confuse the reader, and if I hadn't known what a reductio was before coming here I'd probably just assume it's too complicated for me to bother and move on. Does anyone have an example that does not need to be followed by two paragraphs explaining how it isn't really a reductio, or that it might not be, or that it may be but only if X and Y but not Z, or whatever. - 83.233.147.12 (talk) 12:02, 22 January 2011 (UTC)

Text from previous article

Below copied from previous article. Only relevant to the common reductio ad absurdum, not the proof by contradiction:

---

However, Reductio ad absurdum is also often used to describe any argument where a conclusion is derived in the belief that everyone (or at least those being argued against) will accept that it is false or absurd. This is a comparatively weak form of reductio, as the decision to reject the premise requires that the conclusion is accepted as being absurd. Although a formal contradiction is by definition absurd (unacceptable), a weak reductio ad absurdum argument can be rejected simply by accepting the purportedly absurd conclusion. Such arguments also risk degenerating into strawman arguments, an informal fallacy caused when an argument or theory is twisted by the opposing side to appear ridiculous.

Humour The often humorous outcome of extending the simplification of a flawed statement to ridiculous proportions with the aim of criticising the result is frequently utilised in forms of humour. In fiction, seemingly simple and innocuous actions that are extended beyond reasonable circumstance to chaotic outcomes, typically by use of stereotype and literal interpretation, can also be categorised as reductio ad absurdum. See farce.

Example:

Prove: All positive integers are interesting.

Proof: Assume there exists an uninteresting positive integer. Then there must be a smallest uninteresting positive integer. However, being the smallest uninteresting positive integer is in itself interesting. Thus you have a contradiction and all positive integers are interesting.

Quotations In the words of G. H. Hardy (A Mathematician's Apology), "Reductio ad absurdum, which Euclid loved so much, is one of a mathematician's finest weapons. It is a far finer gambit than any chess gambit: a chess player may offer the sacrifice of a pawn or even a piece, but a mathematician offers the game."

In the first paragraph of the Quentin Section (Part 2: June Second, 1910) of William Faulkner's The Sound and the Fury, Quentin's father, Mr. Compson, gives his son a watch that has been in the family for many generations. His father explains, "It [the watch] was Grandfather's and when Father gave it to me he said I give you the mausoleum of all hope and desire; it's rather excruciating-ly apt that you will use it to gain the reducto absurdum of all human experience which can fit your individual needs no better that it fitted his or his father's". This example represents a corruption of the Latin phrase Reductio ad absurdum.

---

—Centrx→talk • 19:19, 17 April 2009 (UTC)

Removed this due to irrelevance:

== Reductio ad ridiculum ==

Another everyday use of the term reductio ad absurdum even further removed from the pure logical sense simply asserts an absurd consequence without claiming any formal derivation from the proposition.

For example: "If X is true, then I am a monkey's uncle"

Presumably we do not accept that the speaker is really a monkey's uncle, so the 'argument' presented invites us to reject the proposition "X" as equally untrue. This is not really a reductio ad absurdum at all any more, merely a reductio ad ridiculum - an expression of the speaker's opinion that takes a similar form to the strict logical argument.

Isn't this example more related to Ex falso sequitur quodlibet? BertSeghers (talk) 20:12, 13 January 2010 (UTC)

Yes: but only in the ablative, there. Basket _Feudalist 21:33, 31 March 2013 (UTC)

Mathematics Example in Intro

I'm curious about the mathematical example in the introduction. In my opinion that's not an example. It's more a statement of fact that's hard for people to understand because they struggle to grasp the concept of infinity. Sabre ball ^{t c} 14:31, 8 April 2013 (UTC)

To a person familiar with mathematics, I agree, this statement may seem self-evident. But formally, it is a theorem which can be proved from the definition of rational number as shown, using reductio ad absurdam. --Chetvorno^TALK 19:14, 9 April 2013 (UTC)

Strawman vs RAA

I'm really not sure why the reference to the straw man argument is on this page because it seems to me (and I'm no expert by the way) that reductio ad absurdum is not at all the same as the straw man...

A "straw man" argument is always used to attack a position or course of action, by ostensibly showing the bad consequences if that position is upheld; that makes it a reductio ad absurdam argument. The ostensible form of the argument is: "Don't support A, because A will have this terrible result; support not-A instead." It's a reductio because it "...demonstrates that a statement is false by showing that a false, untenable, or absurd result follows from its acceptance".

The difference is that the "straw man" argument is a false reductio, because the premise is misrepresented. The consequence given is not a consequence of the original premise, but of a slightly different premise. The actual form of a straw man argument is: "Don't support A, because B will have this terrible result." The argument is nonsense, a non sequitur. The author of the argument hopes you won't notice this. --Chetvorno^TALK 05:18, 13 January 2013 (UTC)

Not really, a strawman is any time A says X and B responds to X'. It's possible that X is a premise in an argument that B attempts to prove false by constructing a reductio against X', but it's not necessary for this to be the case. — Preceding unsigned comment added by 182.48.140.193 (talk) 10:27, 23 March 2013 (UTC)

No, a strawman is always used to attack a position, not support it, check the defs. B argues that X' should not be supported because a "false, untenable, or absurd result" follows from it. This makes it a reductio. --Chetvorno^TALK 13:01, 11 April 2013 (UTC)

New world Encyclopedia

My understanding was that the New World Encyclopedia is a mirror (or semi-mirror) of wikipedia, and so not acceptable as a source. Yet over half of this article uses that as its source. Unless someone objects, I'll delete these citations in a few days. Original Position (talk) 17:28, 16 February 2016 (UTC)

Removal of example from introduction

Rstrug has repeatedly removed this well-known sentence as an example from the introduction:

Society must have laws, otherwise there would be chaos.

Rstrug has given these reasons in his edit comments:

"Chaos" is subjective. There are a lot of ideas in Game Theory that argue some "laws" are actually natural outcomes.

This is not reductio ad absurdum. You begin with an "absurd" statement that leads to an contradictory conclusion. Chaos is not contradictory, it's deductive.

I think the example is fine and should be put back. Rstrug seems to be arguing about the content of the example. It seems to me he's missing the point, it is the form of the argument, not its content, that makes it a reductio. Whether or not anyone agrees with the sentence, or thinks it is a good argument, the form of the argument is still a reductio ad absurdam.

From the definition, a reductio argument "seeks to demonstrate that a statement is true by showing that a false, untenable, or absurd result follows from its denial". The statement that this example is trying to demonstrate is "Society must have laws". In support of this the sentence argues that if this is denied and society didn't have laws, "there would be chaos". The meaning of "chaos" in this sentence is easy to understand: crime, disagreements or fights between people, auto accidents because people don't know which side of the road to drive on, no prohibitions against offensive or injurious behavior, no defense of contracts or private property. It is saying laws prevent conflict; society without laws would be in a continual state of conflict. This comes under the heading of an "untenable" result; the word "untenable" means unsustainable, unworkable, flimsy, weak, or shaky. It is clear that this sentence is arguing that the result of denying the premise would be an "untenable" society.

Many people, including me, might disagree with this argument. Not the point; it's still a reductio.--Chetvorno^TALK 23:08, 26 January 2016 (UTC)

http://scholarship.law.marquette.edu/cgi/viewcontent.cgi?article=3570&context=mulr

——————

Chaos exists with laws. Order can exist without laws. This is not a reductio ad absurdum because it is not logical. Additionally, there is no citation. Rstrug (talk) 00:11, 27 January 2016 (UTC) rstrug

Again, the question is whether or not the form of the argument is a reductio ad absurdum, not who is for or against it. Thomas Aquinas doesn't address that issue in your reference. And "...falling off the edge of the Earth" (first example) is logical? None of the other examples in the introduction have citations. Sounds like the only real argument you have against this example is that you don't personally like it. --Chetvorno^TALK 03:56, 27 January 2016 (UTC)

Chaos means different things in mathematics than in politics. In the context of the example it is the opposite of laws. Bringing in complexity or chaos theory in this context is not sensible as we are using the common sense meaning of the term in that example. It would be useful to have a citation however ----Snowded ^TALK 07:20, 27 January 2016 (UTC)

Various forms of the sentence appear widely in writings about the philosophy of law: [1], [2], [3], [4], [5] --Chetvorno^TALK 15:03, 27 January 2016 (UTC)

Here is a citation: https://en.wikipedia.org/wiki/Superdeterminism70.126.133.47 (talk) 04:07, 18 March 2016 (UTC)

Suggestion: Why not make it "Society must have laws, otherwise there would be social disorder."

The problem lies in the ambiguity of the words law and chaos, which makes the example elliptical ... Mathematicians overloaded the already perfectly unclear theological and philosophical uses of chaos with their own 'chaos' theories, where the word was specially intended to confuse all non-chaos theorists. ~~

BlueMist (talk) 17:14, 27 January 2016 (UTC)

That would be fine with me. What do you think, Rstrug (talk · contribs)? --Chetvorno^TALK 19:42, 27 January 2016 (UTC)

In Game Theory, cooperation can result in non-cooperative games (Nash Equilibrium). Not every participant will be in disorder; not every participant will be in order. Depending on arbitrary sizes, each system could be categorized as its own society. A society of two people cooperating in the face of adversity does not necessarily have to be dysfunctional. There is an extremely rare possibility that everyone on the entire planet finds a way to cooperate, but it's not impossible.

Additionally, technology and other forces can take the place of "laws." You don't need to pass a law to prevent most people from walking across a minefield naked.

Even in just philosophy, is free will considered chaos and disorder? Rstrug (talk) 21:54, 27 January 2016 (UTC)

Sorry, Rstrug, with your latest remarks you lost me. You now appear to lack the background in any of logic, philosophy, or mathematics to edit this topic. You're giving probabilistic, empirical, and deterministic jargon as your justification.

The way I see it, Reductio is a special case arising from application of binary logic. For a coin that is either heads or tails, if it is not heads then it must necessarily be tails. Absurdum then says that the only other option is impossible (in math) or absurdly wrong (in philosophy). ~~ BlueMist (talk) 23:52, 27 January 2016 (UTC)

And your ad hominem defines your appearance. It's not impossible. Take the corollary. You can pretend people are not breaking the law all you want in your "binary" world, but they still exist. Back to the original criticism. Watch something like the Hunger Games -- even in a free for all, people still cooperated. There was no "chaos" between those groups of people. Rstrug (talk) 15:47, 28 January 2016 (UTC)

"Honor among theives." "Nearly 97 percent of those bets will be wagered illegally." Rstrug (talk) 16:28, 28 January 2016 (UTC)

No one seems to agree with you. And again, you're missing the point. The question being discussed here is not whether "Society must have laws, or there would be chaos", but whether this sentence is a reductio ad absurdam. It doesn't matter what you think of the argument, much less what is in the Hunger Games. It is still a reductio because it "seeks to demonstrate that a statement is true by showing that an untenable result follows from its denial". The fact that you disagree with the argument has nothing to do with what form of argument it is. --Chetvorno^TALK 16:47, 28 January 2016 (UTC)

This is a logical argument that has to make logical sense for it to be logically true. This is not an English class where you can just pop any P and any Q into a sentence and expect it to always work. I don't actually care if people disagree with me. Go ahead and keep living in your fallacious paradox. I did my good deed for the day. If you MUST put this ridiculous assertion back into the article, it MUST have a [citation needed] right next to it. I want to see a complete deductive proof that leads to an explicit contradiction. Rstrug (talk) 17:56, 28 January 2016 (UTC)

The Roman Empire had laws. And collapsed into chaotic anarchy. Pretend that didn't happen. I dare you.Rstrug (talk) 18:00, 28 January 2016 (UTC)

Reductio ad absurdum isn't common sense. Reduction to the average is common sense.Rstrug (talk) 18:36, 28 January 2016 (UTC)

If you had read the part of the introduction which you are editing, you would have seen that a proof by contradiction, in which it is shown deductively that denying the premise results in a logical contradiction, is not the only type of reductio. That was the whole point of the paragraph. The word "absurd" is not synonymous with "contradictory", it can also mean "unworkable" or "impractical" as it does here, and rhetorical arguments don't have "proofs". And did you notice the word "seeks" in the phrase "seeks to demonstrate" in the definition? --Chetvorno^TALK 07:19, 29 January 2016 (UTC)

Define the size of society. An individual can function without the rule of law. A married couple can as well. You can extrapolate form there. Stop pretending this entire school of thought does not exist: https://en.wikipedia.org/wiki/Anarchism. Additionally, here is an entire field of study about people behaving in a predictable manner WITHOUT LAWS: https://en.wikipedia.org/wiki/Game_theory. Rstrug (talk) 22:33, 16 June 2016 (UTC)

This is not an article about the rule of law or civilization or anarchy, this article is about logic. Discussions of these subjects should be made on Rule of law or Anarchy. The article is not pushing the idea that "Society must have laws, otherwise there would be chaos"; it is merely using this common sentence as an example of an argument technique. This is made clear in the introduction. Like you, I don't happen to agree with the sentence, but it is a perfectly good argument which is widely used, and a good example of a reductio. Are you really afraid that just because someone reads that common cliche here he will be inspired to change his entire attitude toward laws? Do you really believe that the way to promote ideas we support is to censor all opposing views out of Wikipedia, even innocuous examples like this in unrelated articles? Come on. --Chetvorno^TALK 00:13, 17 June 2016 (UTC)

You're already ad homineming. There is a list of anarchist communities that existed: https://en.wikipedia.org/wiki/Anarchy. Reductio ad absurdum is not a syllogism. Rstrug (talk) 12:30, 1 July 2016 (UTC)

I have cited other articles from Wikipedia like 10 times. All of those citations have been reviewed by more Wikipedia editors than this piece. Why are you guys pretending you don't see the contradictions? Like seriously. Rstrug (talk) 19:29, 1 July 2016 (UTC)

`We've never seen aliens before therefore reductio ad absurdum aliens are impossible.` That's your argument. It's not an argument. And don't you dare say I started this edit war. It was removed for quite some time. Rstrug (talk) 19:47, 1 July 2016 (UTC)

A statement is not an argument. Reductio ad absurdum is a type of argument. Ergo, the statement cannot be a reductio ad absurdum. BabyJonas (talk) 01:33, 14 July 2016 (UTC)

I don't see how this is even supposed to be an example of a reductio. A reductio is an argument of the form "if [some thing], then [absurdity]; (obviously) not [absurdity], therefore not [the thing]." The example given isn't even a conditional, much less a modus tollens syllogism like that (I'd be OK with omitting the second premise as obvious and the conclusion as tacitly implied from the premises). Something like "if there were no laws, then there would be chaos (and obviously we can't have chaos, therefore we must have laws)" might count as a reductio, except that whether "chaos" is an absurdity or not is a matter of some debate. If we allow this kind of argument to count as a reductio, then "if [policy I don't want] then [thing I don't like]", or "if [thing I don't believe] then [other thing I don't believe]", or basically any modus tollens, would be a reductio too; and obviously, that would be absurd, therefore we can't allow this kind of argument to count as a reductio. --Pfhorrest (talk) 22:44, 14 July 2016 (UTC)

I also find it unconvincing as reductio ad absurdum because "chaos" is not absurd, it's just a state of affairs. The premise that chaos is acceptable could be taken as absurd (that's a point of view, of course, but that's not the point), so "society must have laws, because otherwise it means that chaos is acceptable" would be a reductio. But that is not the same argument, at least not exactly. --Trovatore (talk) 20:20, 17 July 2016 (UTC)

Straw man argument

Why is this here? Just because it is someone's favorite fallacy and they want it on this page as well as it's own? There are any number of ways to reject a hypothesis. Reductio ad absurdum focuses on the fact that *good* arguments based on the hypothesis lead to something obviously false. "Straw man" really has nothing to do with it. 50.202.216.74 (talk) 20:25, 18 November 2014 (UTC)

I've just made a brief attempt to clean up the "Straw man" section. The two sources cited in this version do bring up "straw man" in connection with reduction ad absurdum but they seem like very mediocre sources. Without some better sources and a stronger connection between "straw man" and the topic, then we should probably remove the section. —Ben Kovitz (talk) 02:09, 17 August 2016 (UTC)