Talk:Jetan

The Chessmen of Mars
There are some useful references I found while working on The Chessmen of Mars relating to Jetan, which might be used here. As this article focus is out of my area I have not reworked this article, but perhaps interested parties might look at the material in the novel article page and consider what could be used. Happy to help in any way I can here. Mesmacat (talk) 12:36, 25 February 2009 (UTC)

A Thoat is not a Knight
I removed the italicized sentence in the following:


 * The Thoat take two steps, of which one is orthogonal and the other diagonal; it may jump over intervening pieces. This is equivalent to a chess knight.

This is incorrect. See the following digram. In row 6, a knight's move is pictured: one square orthogonal, and then one square diagonal, forming a 135° angle. A thoat can indeed make this same move, landing on square # 2.

However, in row 2, an actual thoat is pictured, and a different kind of move is shown: one square orthogonal, and then one square diagonal, forming a 45° angle and landing on square # 2. A thoat can make this move, but a knight cannot.

In other words, a Thoat combines the moves of a knight and a king.

Of course, we may speculate that Burroughs did not foresee the 45° move, but the rules as stated in The Chessmen of Mars allow for it. &mdash; Lawrence King ( talk ) 23:45, 16 June 2010 (UTC)


 * The rules are very poorly written, and seem to expect common-sense understanding rather than a literal interpretation. Unless a double capture is intended, why in the world would one describe a move one square to the side as a step forward plus a step diagonally back?
 * This is a problem with a lot of chess variants, where the author did not expect a legalistic approach by his readers. — kwami (talk) 00:04, 17 June 2010 (UTC)


 * Consider the white Chief in row 8 of the diagram. The Chief is allowed "three steps in any direction".  Would you agree that he is allowed to follow the path 1-2-3 in this diagram, completing his move one square to the right of where he started?  Is this a reasonable interpretation of the Chief's rules, or a "legalistic approach"?  If the Chief is allowed to do this, I can't see why the Thoat would be forbidden to do essentially the same thing. &mdash; Lawrence King ( talk ) 00:19, 17 June 2010 (UTC)


 * Because the way the thoat is described is a very common way to describe the move of a knight. The Chief doesn't cause any conflict with common sense. Let's take some of the chess books that were around when Burroughs was younger:
 * Lee & Gossip, 1907: "The Knight moves in a peculiar way, viz., one square diagonally and then one square forwards, backwards or sideways, or vice versa, one square forwards or backwards or laterally and one square diagonally."
 * They go on to say how this combines the shortest moves of the Rook and Bishop, and that intervening men can be jumped, but nowhere mention that your Thoat moves are not permissible; that only becomes apparent with an illustration a couple pages later. Gossip, BTW, wrote another chess book with Lipschütz in 1902, in which he said basically the same thing twice, in two different sections of the book, and more verbosely, without ruling out adjacent squares, though at least one of those descriptions was accompanied by an illustration.
 * After another decade, the restriction was made explicit:
 * Hoffer, 1916: "One move of the Knight combines two King's moves: one square straight, and one square diagonally to any but the adjoining squares to its starting-point."
 * (&c. w jumping). But Burrows was 41 years old when this book came out, 5 years before he published Jetan; he could well have been thinking of the wording of the rules he grew up with, and just took it as obvious that adjacent squares were not intended. And even if he owned a book like Hoffer, his rules were much shorter, and likely to leave out such "superfluous" detail. Compare his account of jumping, "it may jump over intervening pieces", with Hoffer's:
 * "Another privilege of the Knight is, that it may leap over any piece or pawn of its own or the opposite colour intervening between its starting-point and the square to which it moves."
 * That kind of thing was presumably added because of legalistic arguments over what exactly an "intervening piece" was, even though it didn't actually add any factual information. Yes, I know this would be OR to add to the article, but I think it illustrates that we should not assume that people mean exactly what they say even in dedicated chessbooks, let alone in an appendix to a sci-fi novel. The 1902 book, for example, which says nothing about the Knight not moving to adjacent squares, presents itself as The chess-players' manual: containing the laws of the game according to the revised code laid down by the British Chess Association in 1862.
 * Also, how may the Thoat you illustrate "jump over intervening pieces"? There can be no intervening piece. The description in entirely consistent with the move of a Knight. — kwami (talk) 04:11, 17 June 2010 (UTC)


 * With regard to your final question: In any chess-like game, the term "intervening piece" refers to a piece sitting on the path that you want to move along, other than the starting and ending squares.  So in the diagram above, the Thoat on c2 can make the illustrated move (c2 --> c3 --> d2), finishing his move on d2, even if there is an intervening piece occupying c3.


 * With regard to your main point: I agree.  I personally believe that my interpretation of Jetan rules is the best one, because my personal preference is to interpret game rules literally unless it is almost certain that this violates the intention of the authors.  You, on the other hand, have offered different (and very reasonable) criteria:  first, use a "common sense" rather than "literal" understanding; second, use texts that the author might have been familiar with to illuminate his intention.  If we were playing in a Jetan tournament, you and I could present compelling cases to the umpires.  But, as you said, this question is irrelevant to the article itself, because it is clearly OR.  If there actually is a longstanding Jetan tournament, then their interpretation of the rules might belong on this page, but yours and mine does not.


 * Do you agree, however, that I was right to delete the sentence which read "This is equivalent to a chess knight" from the article? That is not a quote from Burroughs, but rather an interpretation of the rules.  It is one that you agree with, but do you also agree that it doesn't belong in the article? &mdash; Lawrence King ( talk ) 04:27, 17 June 2010 (UTC)


 * Also, if we want to avoid all OR, then perhaps several of the existing footnotes on this page should be deleted. Instead, we could state something like, "The rules as stated by Burroughs are not very detailed, and over the years there have been disputes about their interpretation."  We could then cite this page  as a source. &mdash; Lawrence King ( talk ) 04:33, 17 June 2010 (UTC)


 * Yeah, that's probably best.
 * I'm used to obscure shogi variants, where the original wording of the rules is often vague in the extreme, and we end up with English translations which sometimes make no sense whatsoever, like "combines the movement of a rook and a queen" for a piece which can only move once per turn. What you're left with is saying that the only way the move makes sense is with some additional assumptions. The way Jetan rules are worded reminds me of some of the shogi variants. — kwami (talk) 04:41, 17 June 2010 (UTC)


 * Funny! Whereas my background is more in Avalon Hill games, and usually when a rule seems weird we just say "Well, the rules must be right because the playtesters have given it their approval".  Unless we're playing a game with rules written in German -- and since only one of my friends speaks German, he always interprets the rules for us. &mdash; Lawrence King ( talk ) 04:56, 17 June 2010 (UTC)

Image copyright problem with File:Chessmen Mars.jpg
The image File:Chessmen Mars.jpg is used in this article under a claim of fair use, but it does not have an adequate explanation for why it meets the requirements for such images when used here. In particular, for each page the image is used on, it must have an explanation linking to that page which explains why it needs to be used on that page. Please check


 * That there is a non-free use rationale on the image's description page for the use in this article.
 * That this article is linked to from the image description page.

This is an automated notice by FairuseBot. For assistance on the image use policy, see Media copyright questions. --07:16, 11 February 2011 (UTC)


 * I have updated the fair use notice in File:Chessmen Mars.jpg. &mdash; Lawrence King ( talk ) 21:21, 11 February 2011 (UTC)

Board and pieces
The text on the book lists the pieces "in order, as they stand upon the board in the first row, from left to right of each player." (sic) This means that each Chief faces the opposing Princess, not the opposing Chief. I updated the text because the Chief should be at the left of the Princess. The diagram (http://en.wikipedia.org/wiki/File:Jetan_Board.svg) should also be updated because the Chief and the Princess at the top are switched. Yibup (talk) 17:14, 13 June 2013 (UTC)
 * Yes, but that will require the image author to do, since the orange Princess will need a definition outline. (Other option is to make a new image using different icons.) Ihardlythinkso (talk) 03:46, 14 August 2014 (UTC)
 * Should be fixed, now. Ninjatacoshell (talk) 03:01, 15 August 2014 (UTC)
 * Looks great -- thanks! Ihardlythinkso (talk) 04:23, 15 August 2014 (UTC)

Dedicated Publication
Fredrik Ekman (referenced in the footnotes) published a comprehensive book devoted to Jetan, including detailed history of the origin, references in the media, rules, variants and sample games. I couldn't figure out how to include it without tying it specifically to the article text; perhaps someone could do it Anyway, the details are: Jetan: The Martian Chess of Edgar Rice Burroughs Fredrik Ekman Format: softcover (7 x 10) Pages: 211 Bibliographic Info: 149 illustrations, appendices, bibliography, index Copyright Date: 2022 pISBN: 978-1-4766-8793-3 eISBN: 978-1-4766-4761-6 Imprint: McFarland

WHPratt (talk) 18:14, 19 November 2022 (UTC)