2738: Omniknot

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The Gordian knot is an omniknot tied using every bend in the Ashley Book of Knots, and then for extra security the upper rope at every crossing is connected to the lower with a randomly-chosen hitch.
Title text: The Gordian knot is an omniknot tied using every bend in the Ashley Book of Knots, and then for extra security the upper rope at every crossing is connected to the lower with a randomly-chosen hitch.


The comic jokes that if you have several potential knots which could be tied in a given situation, rather than being forced to choose one, you can simply use all of them and create the comic's "Omniknot." The prefix omni- means "all", and so the "all-knot" is the knot containing all the other knots (...that one knows).

Knots in the middle, from top to bottom:

  • Granny knot: A knot that easily comes undone in isolation; usually the result of an improperly tied reef knot. Based upon the visible ends of rope (followed through further knots), could technically be considered a Grief knot.
  • Reef knot: Also known as the square knot, one of the most commonly tied by competent amateurs. But a poor and possibly dangerous choice as a load-bearing bend, as it has a tendency to 'capsize' and untie itself, if the ropes aren't inhibited by other adjacent knots. (A "bend" is a knot that connects two ropes or lines.) Could also be described as a Thief knot, from the visible continuation of the 'ends' as followed through other elements of the omniknot.
  • Sheet bend: Similar to the bowline, a popular, all-round good choice, especially if one rope is thinner than the other. If well tied, the thinner cord will cross over itself. In this case, that would be the line on the lower-right passing through the left, around it, and then under itself.
  • Double sheet bend: A more secure version of the previous knot, especially if one rope is much thinner than the other.
  • Carrick bend: A very good bend, especially if both ropes are both similar in kind and thickness and cumbersome to bend (such as heavy cable) into more common knots.

On the sides are bowlines and each rope is terminated by a figure-eight knot.

The Gordian Knot mentioned in the title text is a knot which purportedly was extraordinarily complex and nearly impossible to untie. According to legend, when Alexander the Great was faced with the knot, he simply drew his sword and cut it in half, thereby "untying" it and solving the unsolvable. The Gordian Knot is now used as a linguistic metaphor to describe a problem whose solution, rather than being to directly solve it head-on, involves working around or otherwise bypassing its apparent constraints, or simply one that is so complex as to be practically intractable.

The Ashley Book of Knots is an encyclopedia describing thousands of different knots. Though it is now dated, because it was written before the widespread adoption of synthetic fiber rope, it is still considered the reference in knot tying. Using all bends from the book and as many hitches would make the final result very complex indeed. Randall proposes here that this was the true origin of the mythical Gordian Knot. A "hitch" is a knot that connects a rope or line to something like a post, loop, or shackle.

In practice, it is not recommended to use overly complex knots, as they provide little in terms of additional security compared to a well-chosen simpler knot. The ease of tying and untying, especially in less than ideal conditions, is also an important factor to consider. If strength is more important than the ease of tying and untying, splices should be considered instead of knots, as they don't weaken the rope as much.

Twitter user HollowGrin created and shared a colorized version to aid tracking the ropes.

Less than a year later a knot was used in 2880: Sheet Bend.


[Two ropes tied together with several different kinds of knots. The ropes enter from left and right. The left rope proceeds to go up where the right rope goes down. But then they interact to form five knots in the middle of the drawing. Following each rope will show the left to interweave the right rope from top to bottom, and vice versa. At the bottom the left rope swings back to where it began going up, ties a knot with itself at the start and the end of the left rope then goes to the right of this knot and ends in another small knot. Similarly the right rope goes back to the right at the top and forms a similar knot with itself, before the end of the rope goes left and ends in the same type of small knot as the left rope. There are thus five knots using both ropes, and two knots on each rope with itself, and the entire thing is yet another combined titular Omniknot, for ten knots in total. There is a caption below the panel:]
If you know several knots and can't figure out which one to use, just tie one of each.

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Down the middle, that's Granny, Reef, ...(k)not sure.., ?bow line and two half hitches? and something of a plaited-knot that the name escapes me entirely right now (but an extension of the other one I can't identify). I'm sure there's a handy online catalogue of knots, to reference, though, before I try to stumble over the side-knots too. 16:05, 15 February 2023 (UTC)

Binding security maximized but unbinding security minimized. RIP, tethered sailor beneath a capsized boat. 16:20, 15 February 2023 (UTC)

This comic is dead on for a facetious rock climbing saying: "If you can't tie a knot, then tie a lot." Based on the tactic some climbing newcomers use, of tying tons of knots all over the place because they aren't confident that any one knot will hold. This tactic is strongly frowned upon - you should learn the right knot, use it, and don't add any extraneous ones.

Somebody on twitter posted an image with the two strings in different colours, which helps to visualize the knots: https://twitter.com/hollowgrin/status/1625902852387352576 Rps (talk) 17:08, 15 February 2023 (UTC)

Feels like this NEEDS to be included in the explanation so I added it. :) NiceGuy1 (talk) 05:19, 19 February 2023 (UTC)
As per adding comment, I'd rather like to see the image in-site. (It's very difficult to open Twitter links without the seemingly undeletable Twitter app opening and telling me I need to get off my arse and get an account, so I tend not to even try.) I bashed up one of my own, for my own pleasure, but I'm not fooling myself that it's any good (basic blue/red masked to each side's rope, with directional chevrons no-masked out to show direction of pull... tried to gradient it to indicate distance as well - that looked awful!) and others' efforts would be nice to see.
(Assuming permission isn't asked for, but refused.) 15:04, 19 February 2023 (UTC)

Damn, I traced it myself and I am pretty sure the picture on twitter is better (I will not look, I will only get depressed...) I'd put that coloured picture under "transcript" ;-) 18:05, 15 February 2023 (UTC)

Nah, transcript is supposed to be all regular text, aggressively so. That link is rather pictorial. :) I added the link to the explanation instead. NiceGuy1 (talk) 05:19, 19 February 2023 (UTC)

I don't suppose any of you knot-loreheads would care to add an explanation/link to explain "Connecting them with a hitch" from the title text? 21:58, 15 February 2023 (UTC)

A "bend" is a knot that connects two ropes or lines. A "hitch" is a knot that connects a rope (a.k.a. line) to something like a post, loop, or shackle.

Is there a mistake in the title text then, since he says to use a random hitch to connect something from the top (presumably rope in the form of a knot) to something in the bottom (presumably more rope)? 22:06, 15 February 2023 (UTC)

I think using a hitch on another rope can be valid, with one rope ACTING as said post, being all straight. For example, a rope pre-secured at both ends, and thus unable to "participate" in the knot, tying a rope to it in-between instead, such as tying a rope to a clothesline.

I tied it in real life. Once everything was tightened, the main taut portion was the Carrick bend with the other four knots slacking below, and it held pretty well. I imagine if the slack was on the other side, putting stress on the granny knot, it would be a different story. I would upload the picture but I messed up the reef knot and that pulled straight out. --Jack (t|c) 22:15, 15 February 2023 (UTC)

Sailor here. The "granny knot" is what a sailor would call a "thief's knot", and it used to be used in place of a reef knot, in some parts of the world, when stores were suspected to be going missing; the thief, after taking some of the stores, would re-lash the remainder using a proper reef knot (through force of habit) and the change of knot would give away that the stores are being taken from that pile.

Additionally, the two bends at the sides look more like sheet bends than bowlines, to me. It just looks like a rope is passed through a bite and then holds the bite together with a half-hitch. (Maybe I just can't get my head around the orientation, though?)

Lastly - is it maybe worth adding that the reason for the figure-of-eights at the tail of the rope is to act as a "stopper" knot, to prevent the tail working it's way back through the half-hitch, which would enable the bite to come apart and the whole thing to come loose? 10:01, 16 February 2023 (UTC)

A note that a Granny knot is not the Thief knot. A Granny is (often!) a mis-tied Reef, half re-handed to create a less flat version of the binding, whilst a Thief is a variation of the Reef, which has the opposite track to one of the cords to look the same at first glance (enough to catch the unwary/rushed, as you say, who might then fail to restore it as originally left).
In fact, a knot that has been given the variations of both Granny and Thief is called a "Grief", rather than be back to the original Reef (or a functionally identical reflection/rotation). 12:26, 16 February 2023 (UTC)
I corrected "bite" to "bight", as that's the correct spelling for a loop of rope or line. 06:02, 20 June 2023 (UTC)
Don't do that. Feel free to explain the 'error', but here in the Discussion pages these are words written by specified people (or at least their IPs) and you can never know if it's an error/a pun/correct in a different dictionary from yours/any other reason that it is 'wrong'. Educate people (or set yourself up to be educated), don't whitewash (perhaps incorrectly) over text that the original author may not even find has been changed. They could possibly be changed to say something they did not intend, and it would need a judgement call to, e.g., disentangle honest (mis)use of an autoantonym from a deliberate vandalism. Anyway, I have reverted your changes, but retained your comment. Not because I actually think it was ever a bad-faith edit (you are right, as far as I'm aware, though I hadn't actually picked it up myself during my own reading and replying here), just that it sets a bad principle. 21:07, 20 June 2023 (UTC)

Both bowlines are the "correctly" tied sailor's bowline. There is an alternative "left-handed" version in which the end goes the other direction, coming out to the side rather than the interior of the knot. Also called the cowboy bowline, ABOK 1034.5 It is unclear which version is better. One could probably do a PhD dissertation on bowline knots. 14:35, 16 February 2023 (UTC)

Scoutmaster here. I recommend the "Animated Knots by Grog" website as a knot reference. The Wikipedia entries on granny and grief knots are surprisingly useful references for how those knots differ from each other and the reef knot.
The knot on top is definitely a granny knot and not a grief knot. I was wrong.  :P Since the ends that terminate the knot exit on opposite sides instead of the same side, calling it a grief knot is not wrong.
Left and right knots are bowlines because they have three working ends and one dead end. The sheet bend has two live ends and two dead ends. The center knot is indeterminate; if you cover up the ends it could be either a sheet bend or a bowline, as they have the same form. Since it appears to have four live ends it would be fair to call it "neither" as well. PhD thesis topic, indeed.
I'd also like to point out that the capsizing nature of the reef knot is considered a feature - it affords easy untying even after being used under heavy load, such as holding a rolled up sail hanging from a yard arm. Being able to unfurl the sail by pulling a single rope is useful. As already noted on the page: if you don't want that feature, pick a different knot. 14:56, 16 February 2023 (UTC)

You can't really tell a difference between Granny and Grief (and Reef and Thief) in the above as there's not really a 'loose end' from any of those. Following all cords, the visible ends ending with the stoppers or the off-screen ends (possibly coming back on-screen from the other side, in a large loop, but we can't know that) always goes through multiple other knotted segments. Although I'd say Granny (and Reef) as default is certainly the simplest interpretation.
And an uncollapsed Reef tends to jam itself, to not simply undo. You need to force it (or rely upon it rotating, through (improper?) use) to make it into a "cow hitch around a straight rope" form and thus an easier untie. Which you can only do if you have sufficient slack on one 'end'.
(Not sure you could guarantee it capsizing, deliberately or incidentaly, in the omniknot situation once the whole mass gets strained. And there's no way that Reef segment can undo itsef, without plenty of other knot-failures happening, even if it does re-wrap...) 18:36, 16 February 2023 (UTC)
Yes, forcing a reef knot to capsize requires abusing the knot; i.e. applying a load onto one of the formerly loose ends. It takes less force than you may think. Try it sometime! I have occasion for this most often with kids' shoestrings. 03:37, 18 February 2023 (UTC)

According to at least one interpretation I've heard, the origin of the Gordian knot story is the use of a complex knot as a sort of tamper evident seal. It won't stop a determined intruder, but it will let the the owner know someone has violated the seal (because the rope is either loose or tied back differently), and let the would-be violator know that the violation they might be considering won't go unnoticed. 16:27, 16 February 2023 (UTC)

"it is knot recommended to use overly complex knots ..." -- is this meant as a joke? the wrong not is used before recommended

Of course, obviously. :) There's no doubt in my mind. Explain XKCD editors can't help adding jokes and puns wherever possible, and this one is somewhat required, LOL! (Also, sign your comments, please) NiceGuy1 (talk) 06:15, 19 February 2023 (UTC)

Made it: https://imgur.com/gallery/cYQQPKq Mikemenn (talk) 16:06, 19 February 2023 (UTC)Mikemenn

Does the omniknot of all knots which do not contain themselves contain itself? 21:47, 15 January 2024 (UTC)