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Eliminating the Impossible

|< < Prev #3210 (February 20, 2026)

Title text: 'If you've eliminated a few possibilities and you can't think of any others, your weird theory is proven right' isn't quite as rhetorically compelling.

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Explanation

The discussion in this comic plays upon the phrase originating from the fictional Sherlock Holmes (and therefore also his author, Arthur Conan-Doyle) that "When you have eliminated all which is impossible, then whatever remains, however improbable, must be the truth," which describes Holmes's abductive reasoning used to solve the crimes and mysteries set before him. The point of the original statement is that something being unlikely does not make it untrue, and ignoring reality because it is "unlikely" is both absurd and counterproductive to the process of solving a problem. However, this statement is a fallacy, as nobody is omniscient so it is impossible to rule out all alternatives.

In the real world, it is never true that eliminating the impossible leaves only a single possible outcome. There are always vast numbers of events that are technically possible, but so vastly improbable that they would be unlikely to ever be observed, even if every subatomic particle in the universe were a universe itself, and were to be observed from Big Bang to heat death. An example would be quantum tunneling of a macroscopic object over a long distance... such as a set of keys from inside a house out to a car. In practice, such events are usually dismissed from consideration.

White Hat is expounding this principle, to Cueball, as a logical step for some undisclosed purpose. Cueball argues that human error - namely, making a mistake in the 'elimination' process - is also possible, and claims that the logic is faulty on this premise. When White Hat points out that the logic is a guideline for problem-solving, Cueball argues that the possibility of human error when operating on this logic makes the approach unsound. If there is one true version of events, then finding it by this process requires classifying all other possibilities as impossible. While that might be possible for a constrained problem like a detective story or multi-option question, many daily situations require eliminating vast numbers of possibilities while lacking sufficient information to be truly sure that the possibilities have been exhausted.

In the final panel, Cueball demonstrates a practical example of human error causing this issue. When a person is looking for their possessions, their first option is to search the house in which they presently are, while their second option is to search their mode of transportation (especially in the case of possessions that are regularly brought to and from other locations). White Hat agrees that he himself has been in the situation where he has searched the entire house, not found what he is looking for, assumes it is in the car, and then fails to locate it in the car as well. There are other possibilities, but the tendency to jump to conclusions (possibly by misuse of the quote) can lead to those being ignored. Additional possibilities:

• The house has not been fully searched, with the item left in some obscured corner, a clothing pocket that is in the laundry, or even a vent or pipe that one could not practically access.
• The car has not been fully searched, because the item slid between two seats or was deeper in a glove compartment than the searcher thought possible.
• It is common for people to fail to see a thing even though it is present, sometimes even clearly in view, because of momentary cognitive glitching, poor assumptions, or more fundamental cognitive failures such as visual agnosia. Another Holmes quotation is relevant: "You see, but you do not observe."
• The searcher forgets that they took the item to some other location, or wishfully ignores that possibility because it is far away and/or inconvenient to search.
• The searcher has never taken the item anywhere other than the house or car, but is unaware that someone or something else moved it.
• The item may have been destroyed or altered in a way that makes it unrecognizable when found.

The title text goes further in deconstructing how the quote might result in a logically incorrect argument from ignorance. In fiction, there is a Law of Narrative Causality, by which events are successfully resolved in the way that the plot requires them to be resolved; therefore, stating this approach as a logical rule would normally be narratively unsatisfying. When Sherlock Holmes first uses the phrase in The Sign of the Four, he "deduces" that Watson had sent a telegram at the post office instead of doing anything else by observing that he had not written a letter and that he already had a good stock of postcards and stamps. Holmes neglects the possibility that Watson had written a letter the previous day to send, or any other possibility, yet he happens to be right because it would be unsatisfying were he to be wrong. Humorously, he claims in the same chapter that "I never guess".

Sherlock may have more accurately, yet less memorably, phrased the maxim as "When you have eliminated what is likely, the truth must be in a more improbable outcome".

Transcript

This is one of 46 incomplete transcripts: Don't remove this notice too soon. If you can fix this issue, edit the page!

[White Hat and Cueball are standing together and talking. White Hat has one hand slightly raised.]

White Hat: As Sherlock Holmes said,

White Hat: When you have eliminated the impossible, whatever remains, however improbable, must be the truth.

[Close-up of Cueball's head.]

Cueball: What about the possibility that you forgot to eliminate a possibility?

Cueball: Or that you eliminated one incorrectly?

Cueball: Both of those remain, too.

[Zoom back out to show both. Cueball holds his arms out.]

White Hat: You're being pedantic.

White Hat: It's just a general rule for deduction.

Cueball: But it's a bad rule.

[Cueball holds up one finger.]

Cueball: How often have you thought, "I can't find this thing, and I've searched the whole house. The only place I haven't looked is the car, so it must be there."

White Hat: ...and then it's never in the car.

Cueball: It's never in the car!

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Make changes, try things out, or just have fun with the wiki here! Just leave everything above the line alone, please.

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This is a test. PoolloverNathan^{[stalk the blue seas]} 20:48, 16 March 2021 (UTC)

This is not. —While False (museum | talk | contributions | logs | rights | printable version | page information | what links there | related changes | Google search | current time: 00:56) 18:38, 17 November 2022 (UTC)

A foreign student asked me to help fight against his math teacher. That was unusual. He was in that class for just a couple of weeks. The teacher's phone number was sent to me. The student asked me to spam-call the teacher. 172.71.155.55 22:58, 18 September 2023 (UTC)

here i'm just messing around in html, ignore this

^furhhfghure _{guyrburgryhuyvfr} "rvhru"

interesting way of writing quotations xd

hmmm this one of putting "<p>" in a line break will come in handy for when i want it to start at the same place than the first line

Please beware that <p> on mediawiki also disables automatic paragraph breaks, so you need a closing </p> or you'll break automatic paragraph formatting for the rest of the page. Zmatt (talk) 22:06, 31 July 2024 (UTC)

edit: da hek did that "</div>" come from An user who has no account yet (talk) 14:14, 13 October 2023 (UTC)

hi uh its hard to get here. is this a reference to undocumented feature??? hmm... this is interesting.
108.162.241.216 02:05, 23 November 2023 (UTC)

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yum yum [citation needed]

Hiuiedeixgeyceiyedhcdiedcve {{trout}}

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<a href=" [AT THE JULY 28TH MEETING][tab] "Cancel the meeting! Our cover is blown.">

More testing: hello ​ does​this​work (yes​it​does) This isn't a good name (talk) 22:44, 28 January 2026 (UTC)
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Recent comments:

21 February 2026

22:05

Talk:2061: Tectonics Game‎ (diff | hist) . . (+549)‎ . . 2001:4c4e:1c15:5800:199:f329:a038:448f (talk) (A3V is 8600 K, coinciding with the high end of blue dwarfs)

		22:01	Talk:3210: Eliminating the Impossible‎‎ (13 changes | history) . . (+5,288)‎ . . [Nerd1729‎; MithicSpirit‎; EebstertheGreat‎; Dúthomhas‎; Arcorann‎; 2a02:3100:25a0:9400:6ceb:97ff:fe5b:8bdc‎; 2604:3d09:84:4000:6ffb:f472:7679:ff75‎; 174.130.97.11‎; Promethean‎ (2×); 81.179.199.253‎ (3×)]
			22:01 (cur | prev) . . (+307)‎ . . Nerd1729 (talk | contribs)
			21:27 (cur | prev) . . (+278)‎ . . Dúthomhas (talk | contribs) (Sherlock Holmes was not wrong (about himself))
			20:43 (cur | prev) . . (+531)‎ . . MithicSpirit (talk | contribs)
			14:25 (cur | prev) . . (+577)‎ . . 81.179.199.253 (talk)
			14:20 (cur | prev) . . (+1,313)‎ . . EebstertheGreat (talk | contribs)
			14:16 (cur | prev) . . (+53)‎ . . 81.179.199.253 (talk) (*I* very nearly said something like that, in response... But I'd have not messed up the signature bit, in doing so. ;))
			14:10 (cur | prev) . . (+9)‎ . . 174.130.97.11 (talk)
			11:06 (cur | prev) . . (+180)‎ . . 2a02:3100:25a0:9400:6ceb:97ff:fe5b:8bdc (talk)
			09:23 (cur | prev) . . (+419)‎ . . Arcorann (talk | contribs)
			02:34 (cur | prev) . . (+176)‎ . . 2604:3d09:84:4000:6ffb:f472:7679:ff75 (talk)
		m	00:39 (cur | prev) . . (+58)‎ . . Promethean (talk | contribs)
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21:42

Talk:2111: Opportunity Rover‎ (diff | hist) . . (+97)‎ . . 180.181.250.224 (talk)

15:26

Talk:12: Poisson‎ (diff | hist) . . (+154)‎ . . Xkdvd (talk | contribs) (Random comic button might not be as broken as it seems...)

20 February 2026

		14:35	Talk:803: Airfoil‎‎ (3 changes | history) . . (+1,086)‎ . . [Xkdvd‎; 82.132.239.77‎ (2×)]
			14:35 (cur | prev) . . (+185)‎ . . 82.132.239.77 (talk)
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		14:16	Talk:246: Labyrinth Puzzle‎‎ (2 changes | history) . . (+205)‎ . . [82.132.239.77‎; 180.181.250.224‎]
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		14:13	Talk:2839: Language Acquisition‎‎ (2 changes | history) . . (+75)‎ . . [82.132.239.77‎; 131.242.7.53‎]
			14:13 (cur | prev) . . (+52)‎ . . 82.132.239.77 (talk) (Was added as an alteration of a prior comment. Did not even look like a revisiting IP modifying their 2½-year-old contribution, but technically a 'reply' , so redone as a reply (rather than reverted away as unwanted vandalism).)
			02:23 (cur | prev) . . (+23)‎ . . 131.242.7.53 (talk) (13, not 12)

19 February 2026

		23:58	Talk:3208: SNEWS‎‎ (3 changes | history) . . (+889)‎ . . [81.179.199.253‎; 2001:16b8:cc31:8a00:4965:59fd:4204:21d7‎ (2×)]
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