Mahjong Stars

The Fundamentals of Riichi Mahjong
By Nima
Intermediate Lesson 2

As with any other game, mastering the fundamentals is essential to becoming a skilled player. There are no shortcuts. No amount of advanced strategy will do any good if your fundamentals are poor. In the case of riichi mahjong, the fundamentals would be “digital” theory.
You may have heard about a digital style of mahjong in other contexts. At its simplest, digital play is making decisions that will give you the best results on average, over a long period of time. There are hard rules on what you should do in common situations based on statistics taken from a large number of games. There are entire books written on what you should do in various conditions with the data to support their assertions.
In this way, digital theory provides players with a “right” and “wrong” in the incredibly complex game of riichi mahjong. That being said, you can still make a “correct” decision that causes you to lose, and you can still make an “incorrect” decision that works in your favor. Anything can happen in a single game of mahjong, which is what makes it so exciting. But that also makes it difficult to improve if you fixate on the wrong things. Digital theory is based on a large number of games, so you cannot base its effectiveness on just a small handful. You should learn digital theory with the expectation that it will help you out in the long run.
Next, let us go even further, to the most basic aspect of digital theory, and what I believe to be the foundation of riichi mahjong strategy: “tile efficiency”*. Tile efficiency, at its core, is about completing a hand as quickly as possible, regardless of value. You need a solid grasp of tile efficiency to be able to learn more advanced concepts. When making decisions about how to pursue value or hold safe tiles, you are doing so at the expense of tile efficiency. Without an adequate understanding of tile efficiency, you cannot know whether or not these tradeoffs are reasonable.
I cannot understate how important tile efficiency is to improving past a basic level in riichi mahjong. It is a subject many players skip over; after all, the most efficient discard should just be common sense, right? It is not the most glamorous subject, either. However, tile efficiency is not as simple as it may appear at a glance. It is the foundation of riichi mahjong strategy, and everything else just builds on top of it. There are no shortcuts to getting better at riichi mahjong, so you have to make sure you have tile efficiency down before moving on.
There are a few places where you can learn about proper tile efficiency and digital theory, but the most comprehensive source by far is Riichi Book I, by Daina Chiba. It is the best English resource on these subjects, and I highly recommend reading it. That being said, reading that book will not be enough on its own. You also have to apply the concepts you learn from it to your own play. I recommend focusing on one section at a time so as not to get overwhelmed.
Once you are done reading Riichi Book I, you could see how well you understand it by taking an online test that I made. You can find it here. Do not take it lightly; it was not made to be easy. Riichi Book I has a lot of information, but if you can master its concepts, then you are well on your way to becoming a strong mahjong player. Just remember that improving will take time and effort; there are no shortcuts.
*The term “tile efficiency” (牌効率) was thought to have first been used by Yukio Oshida, the current chairman of the professional organization, Mahjong Union -μ-. According to Mahjong Techniques Textbook: How to Win Efficiently (麻雀技術の教科書: 効率的なアガリ方) by Gou Kobayashi and Yousuke Ide, tile efficiency is about playing in a way that gives you the best chance of winning your hand the fastest. They note that this is not the same as simply being the first player to make their hand tenpai. Page 12 of the book states, “Not worrying about the ukeire (tile acceptance) of the hand in front of you and instead building a final shape that is more likely to win will actually increase the probability of completing the hand.”

Yukio Oshida
