Anzan

You learned the soroban. Now learn to put it away — and keep calculating.

Anzan is the art of doing arithmetic on a soroban you can no longer touch: an abacus held entirely in the mind, its beads moved by memory instead of fingers. Skilled practitioners add long columns of figures, multiply, and divide faster than most people can reach for a calculator — not through tricks or rote memorization, but by building a vivid, reliable mental image of the instrument and learning to work it in their heads.

This book is the sequel to The Soroban: A Modern Guide for Adult Beginners, and it is written for the same reader: a patient adult who wants to understand what they are doing and why, one honest step at a time. It assumes you can already work a physical soroban. From there, it carries you all the way from picturing a single rod to summing dictated numbers, reading flashed digits, and calculating products and quotients without ever lifting a hand.

Most mental-math books hand you shortcuts. This one builds a skill. Every technique is introduced as a single new variable added to something you already do, so you always know exactly what you are practicing. Every chapter ends with a clear gate — a concrete standard to meet before moving on — so you are never left guessing whether you are ready. And every one of the book's hundreds of practice problems has been individually checked against its answer, so the drills you train on are correct.

Across four parts and fourteen chapters, you will move through:

The Mental Instrument — forming a stable bead-image, weaning off your fingers, and calculating on a single rod in your head.

Mental Addition and Subtraction — carries and borrows across the tens boundary, three-rod images, and the sweep-and-relay methods that keep wide numbers from collapsing.

Speed and Scale — mitori-anzan (adding columns at a glance), yomiage-anzan (calculating from dictation), flash anzan, and building genuine endurance over long chains.

Making It Permanent — mental multiplication, a genuine rolling method for mental division, a maintenance system that keeps every skill sharp, and using anzan for real-world accuracy and estimation.

The book also includes a readiness diagnostic to confirm you are prepared to begin, a twelve-week practice route, a complete glossary of Japanese soroban terms in romanized form, a full answer key for every exercise, and notes on the research into how mental-abacus calculation actually works in the brain. Clear diagrams throughout show each stage of the imagined instrument as it changes.

Whether you want faster everyday arithmetic, a genuine cognitive challenge, or simply to finish what you started with the soroban, Anzan gives you a complete, tested path from the physical bead to the mental image.

Pick up your soroban one last time. Then learn to leave it on the desk.