2348: Boat Puzzle

Explain xkcd: It's 'cause you're dumb.
Revision as of 01:52, 20 August 2020 by 172.69.34.56 (talk) (Transcript: categories)
Jump to: navigation, search
Boat Puzzle
'No, my cabbage moths have already started laying eggs in them! Send the trolley into the river!' 'No, the sailing wolf will steal the boat to rescue them!'
Title text: 'No, my cabbage moths have already started laying eggs in them! Send the trolley into the river!' 'No, the sailing wolf will steal the boat to rescue them!'

Explanation

Ambox notice.png This explanation may be incomplete or incorrect: Created by a GOAT THAT EATS WOLVES. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.
If you can address this issue, please edit the page! Thanks.

This comic is a twist on an old riddle. In the original riddle, a person has to cross a river in a boat that can only hold them and one other object. They have a wolf, a goat, and a cabbage that they need to bring across with them, similar to the first panel. If the wolf is left alone with the goat, however, the wolf will eat the goat; and if the goat and cabbage are alone, the goat will eat the cabbage. (The problem can be solved in seven trips.)

However, the comic quickly devolves into surrealism in the later panels as new characters show up, bringing deviations of the original "cabbage", "goat", and "wolf" that add extra layers of complexity to the riddle. White Hat brings extra wolves and cabbages, Black Hat brings cabbage moths, who presumably cannot be left alone with cabbages, and boat-destroying termites. How he intends to bring them across the river is unknown, but it brings to mind the parable of The Scorpion and the Frog. "Farmer Hat" (?) arrives with a wolf who can operate a boat, who could perhaps serve as a second pilot to expedite the crossing, so long as he is not asked to ferry a goat, and also a goat who eats wolves (which does not alter the problem constraints but is unusual).

The last panel is a reference to the Trolley Problem, a moral test that asks the participant whether they would let a person in the way of an uncontrollable trolley die or divert the trolley and kill other people standing on the tracks. The comic gives a twist here too: according to the title text, the characters must choose between stopping the trolley full of wolves with a cushion of cabbages (in which the cabbage moths have laid eggs, which the speaking character treats as morally equivalent to "innocent children") or letting it crash into the river (at which point the wolf who can operate a boat will steal the boat to rescue the wolves from the trolley, which will delay the other characters from crossing the river).

The River Crossing puzzle was also mentioned in 1134: Logic Boat and referenced in 589: Designated Drivers.

The Trolley Problem was also mentioned in 1455: Trolley Problem and referenced in 1938: Meltdown and Spectre.

Transcript

Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.


comment.png add a comment! ⋅ comment.png add a topic (use sparingly)! ⋅ Icons-mini-action refresh blue.gif refresh comments!

Discussion

A link could be made to this wiki entry https://en.wikipedia.org/wiki/Wolf,_goat_and_cabbage_problem#Occurrence_and_variations . Also the last panel is seemingly a reference to the trolley problem https://en.wikipedia.org/wiki/Trolley_problem

Callback to strip 1134. https://xkcd.com/1134/ I don't know how to add a proper link. Pete 162.158.154.71 22:23, 19 August 2020 (UTC)

Oh boy someone out there is gonna get nerd-sniped real hard Fieldbox (talk) 23:48, 19 August 2020 (UTC)

Some thoughts I had:

- There's a hierarchy: Wolfeater -> Wolves -> Goats & Cabbage moths -> Cabbages

- Does Wolfeater also eat cabbage? Yes. It's a goat

- There are additional weapons for Rock paper scissors

- Black Hat's moths and termites could obviously be transported so far (Black Hat might lie, source needed), but in the spirit of the question: moths can't be left alone with cabbages, and termites will destroy the boat if a crossing with them is attempted

- Cabbages can cushion the trolley, and still function as cabbages afterwards. Use White Hat's, because he has 100/101 cabbages, Ponytail's 1 cabbage adds less than 1% to the cushion, and if it's a special kind (probably not in the spirit of the question), it would get jumbled with the rest of them in the cushioning

- 6 humans to keep an eye on things, instead of the normal 1

- Trolley doesn't get to cross. It can hold multiple wolves, let's say at least 3, and if the trolley could cross, then Cueball wouldn't hesitate to recommend Ponytail go across with her 3 items Coverbe (talk) 05:03, 20 August 2020 (UTC)

Relevant: "Rubicon" https://www.youtube.com/watch?v=f-ROdRgRRsY 162.158.159.14 07:28, 20 August 2020 (UTC)

Question: is the wolf-eating goat the same goat as the goat that Beret Guy won from Monty Hall? 172.69.63.247 15:53, 20 August 2020 (UTC)

On "Reasonable assumptions": "Stopping the trolley destroys all the cabbages. Otherwise the event does not affect the logic puzzle" - This could be a red herring. And: We can still see the cabbages as 2 groups: 1+100. Destroying White Hat's 100 still lets Ponytail's 1 survive intact

"The pack of wolves in the trolley, if rescued, will eat a human or wolf eating goat left alone" - This phrasing is strange. If part of it means "wolves will eat the wolf-eating-goat": I disagree. See rock-paper-scissors Coverbe (talk) 16:25, 20 August 2020 (UTC)

If you have (any) single wolf and (any) single goat alone on one side as you depart, upon your return you will probably discover either a wolf-eating-goat or a wolf eating goat. Which it is, will obviously depend upon the finer details, but it's a failure both ways... 162.158.159.14 18:29, 20 August 2020 (UTC)
That I agree with. I still wonder about "The pack of wolves […] will eat a human […]". I think it's a more reasonable assumption that any human can control any number of wolves Coverbe (talk) 19:03, 20 August 2020 (UTC)
That's a patently absurd suggestion in any other context, and arbitrary at best here. GreatWyrmGold (talk) 16:23, 24 August 2020 (UTC)

What if only Cueball of all the humans can row the boat? He could be the ferryman172.69.2.166 18:19, 20 August 2020 (UTC)

But no-one's allowed to use the boat if they haven't figured out their eye color yet. (Assume the people, goats, wolves, moths, and termites are all perfect logicians. Assume the water is unreflective, the trolley has no windows, and Cueball makes his spreadsheet without looking at a screen. Assume everyone is a very bad communicator outside of announcing their logical predicaments. Assume that Black Hat will strictly enforce these guidelines.) 108.162.219.18 19:31, 20 August 2020 (UTC)

"The pack of wolves in the trolley, if abandoned by the humans and rescued by the wolf who can operate a boat, will eat a human or wolf-eating goat left alone." - This seems really needlessly complex and doesn't really have a bearing on the problem in general.

Yeah, not sure that's better.Sturmovik (talk) 02:45, 21 August 2020 (UTC)

Given Beret Guy's surrealist nature, maybe the solution is to send him across in the boat alone, then he can return with one item: the opposite bank. 162.158.159.18 17:08, 21 August 2020 (UTC)

Certainly worth bringing up to him, I'd say. Also, thanks for the chuckle -- 162.158.186.196 19:27, 25 August 2020 (UTC)