How to Read a Sedis Tile and the History of Generic Game System Design
Previously, I asserted (and validated) that Sedis is only the fourth extant “generic gaming device” – a system of of game tiles, with similar and deliberate piece design, with which a large variety of games can be played. Now, I want to delve further into of how Sedis is actually designed. But, first, let’s start with a brief history of how the other three generic gaming systems – dice, dominoes, and playing cards – are designed.

Terracotta dice at Archaeological Museum of Delos, Greece via Wikimedia Commons
Dice is the simplest gaming device, because historically each die is identical in configuration to the others within a set. There are exceptions to this, especially in the modern era of role-playing games. The traditional die is a cube, with each of six faces showing a different number of pips/dots, indicating the number represented, thus ranging from one to six. Dice are typically used as a random device in the context of whatever game is being played. Dice likely originated in the ancient Middle East and ancient dice have been found at archaeological sites such as Sumeria1, Egypt2, the Roman Empire3, China4 and India5.
Dominoes are derived from dice and show the same pip configurations as if two dice were thrown simultaneously, thereby eliminating duplicate combinations. Dominoes are thought to have originated in ancient China in the 12th century CE6. Chinese dominoes, which consist of 21 tiles, are somewhat different in their configuration than the more widespread European dominoes which, while derived from the Chinese set, added tiles with blanks (essentially, zero pips), bringing the tile count to 28 in the 18th century7. Both of these sets can be referred to as double-six sets, as the highest-ranked tile generally consists of two halves with six pips each. Later, double-nine and double-twelve sets were introduced, but the double-six sets continue to be the most used8. An important note is that, unlike dice, a dominoes set consists of individual members which are derived from the same underlying method but differ from each other slightly.

Mamluk playing cards c. 1500. via Wikimedia Commons
Playing cards have a long and interesting history. Like dominoes, cards likely originated in China – in this case, in the 11th century CE or before9. There is some ambiguity around this, as the first playing cards likely depicted a Chinese domino pack, but Chinese dominoes are not thought to have existed until the 12th century CE. Regardless, Chinese dominoes were split into two distinct (but unequal in number) suits. The notion of more suits entered into playing cards through Persia, in the form of the Ganjifa – and later, in the form of the Mamluk cards of Egypt10. The modern, international deck of 52-playing cards (13 ranks across 4 suits) seems to have been developed in Europe in the 14th through 17th centuries CE and likely evolved from the Mamluk cards. The most common deck in use today is called the French deck (52 cards), which is comprised of the familiar 13 ranks (Ace, 2-10, Jack, Queen, King) across four suits (spades, clubs, hearts, diamonds). Like dominoes, the modern playing card deck consists of a systematized approach with each card a unique member derived from the same underlying method of configuration.
Before I go into Sedis, let me offer a warning: many people may read what is below and be fearful of the ‘mathematics’ behind the design of Sedis. This is exactly the opposite of what I hope for; you do not need to understand the method by which Sedis tiles are designed in order to enjoy – and do well at – playing the games using the set. The following is offered only to inform the reader who is interested in how the system of tiles is developed. So, please… don’t let what’s ahead in this post scare you away from Sedis!
Sedis has a more complex derivation than these previous generic gaming devices, but a complete set of sixty tiles was still developed using a basic system of design, and each tile is unique in its configuration. Each Sedis tile consists of six sides, and each side has five spaces (also called indicia). Of these five spaces, between one and three on each side are darkened, called pips (as per the dots on dice and dominoes). Furthermore, only one side on each tile – the top side in the drawing below – has three pips; the others have one or two pips.
The 3-pip side of each tile is called the ‘primary side’ of the tile – and not just because it has the most pips. The pips on all the other sides of a single tile are subsets of the primary side, which I’ll explain further:
First, let’s introduce a convention of naming the spaces. Let’s scan the tile from its center outward, then label the spaces left-to-right as 1 to 5, as in the illustration below.
This particular tile has, on its 3-pip side, pips in the 2nd, 4th and 5th spaces. Let’s call this a 2-4-5 side on this tile. Every Sedis tile has one side with three pips – its primary side – and there are ten possible combinations. So, the entire set of 60 Sedis tiles can be broken down into ten ‘families’ – with each family consisting of six tiles which share the same primary side. The illustration below shows the primary sides of the ten families.
Now, let’s rotate the tile and look at each of the sides. First, we’ll look at the three 1-pip sides. The illustrations below show the same tile as above but rotated by 1/6, 3/6 and 5/6 counter-clockwise rotations. (Check for yourself.) Now, here’s something interesting. Recall that the 3-pip side on this tile had pips in the 2nd, 4th, and 5th positions. The 1-pip sides on the same tile each has one of these pips (from left to right in the illustration below, Pips #4, #2 and #5. In fact, this is not a mere coincidence. It’s part of the method of how Sedis is designed; every tile has three 1-pip sides, each of which is a unique pip from the primary side of the same tile.
Given that there are three sides/places for these three pips, there are six unique configurations of any three pips along these sides. (I won’t go into the details here, but you can verify this yourself, if you’re so inclined.) Now, recall that there are ten families – sets of tiles with the same primary side. Combined with six unique configurations of distributing the three pips to the three 1-pip sides, we get 60 tiles total (ten families with six tiles each).
But, we’re not done. There are still two sides to each Sedis tile – the 2-pip sides. Let’s rotate the above tile a bit more (in this case, 2/6 and 4/6 of a full rotation from the original orientation). Note that each 2-pip side lies adjacent to two 1-pip sides – again, by design. The pips on the 2-pip sides are simply derived by combining the pips on each of the adjacent sides. So, you have what appears in the following illustration; for example, in the left image, the 2-pip side labeled 2-4 is simply the combination of the adjacent 1-pip sides, with pips in the 4th and 2nd position.
In summary, each tile contains a primary, 3-pip side. These three pips are then distributed individually (and without duplication) to the three 1-pip sides. The 2-pip sides are derived by combining the single pips on the adjacent 1-pip sides. This results in 60 unique tiles with interesting properties.
First, Sedis is complex and rich, but relatively easy to understand (once you get used to the patterns). For example, if you want to know what may be on a tile, it’s not necessary to scan the whole tile; reading the primary side of the tile will give you a general sense of the pips on the other sides (but not their orientation) and – perhaps more importantly – will tell you what is not on the other sides. (In the example above, the primary side is a 2-4-5, so we can know immediately that the tile does not have any pip in the 1st or 3rd spaces on any side.)
Second, this system of configuration allows for interesting game mechanics and game rules, as well as interesting visual effects. One example of this is the game Rings, in which players attempt to create rings, each consisting of six Sedis tiles, by matching pips along adjacent tiles using only the 1-pip sides. Because the 1-pip sides only appear on alternating sides along the tiles, this creates aesthetically-pleasing geometric shapes, as in the photo below. And, that’s the point of Sedis – to be an interesting, useful evolution of ‘generic gaming devices’.
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References
- Laird, Jay (2009). Encyclopedia of Play in Today’s Society. SAGE Publications. pp. 171–173.
- Finkel, Irving (2008). “Board Games”. Beyond Babylon: Art, Trade, and Diplomacy in the Second Millennium B.C. Metropolitan Museum of Art. p. 151
- Matz, David (2002). Daily Life of the Ancient Romans. Greenwood Publishing Group. pp. 94–95
- Ronan, Colin; Needham, Joseph (1986). The Shorter Science and Civilisation in China. Cambridge University Press. p. 55
- Michon, Daniel (2015). Archaeology and Religion in Early Northwest India: History, Theory, Practice. Routledge. p 183-200
- Lo, Andrew. “The Game of Leaves: An Inquiry into the Origin of Chinese Playing Cards,” Bulletin of the School of Oriental and African Studies, University of London, Vol. 63, No. 3 (2000): 389-406.
- Rodney P. Carlisle (2 April 2009). Encyclopedia of Play. SAGE. p. 181.
- Hoyle, Edmond; Dawson, Lawrence Hawkins (1950). Hoyle’s games modernized. Routledge & Kegan Paul.
- Wilkinson, W.H. (1895). “Chinese Origin of Playing Cards”. American Anthropologist. VIII (1): 61–78.
- Playing Card, Wikipedia entry.