Mind Performance Hacks

Hack #39. Turn Your Hands into an Abacus

You might have heard stories of how rapid and accurate calculations with an abacus can be, but did you know that the abacus might have been based on an ancient technique using only the human hand, which survives today as the Korean art of Chisenbop?

Chisenbop is an ancient Korean technique for calculations with the human hand. The classic text on Chisenbop in English is The Complete Book of Fingermath.¹ Unfortunately, it is expensive, aimed toward children, and takes hundreds of pages to explain principles that an educated adult can learn in a few minutes. One important thing that the book can offer you, however, is page after page of drills. Chisenbop should become a motor skill, not something you have to think about.

Fingermath also uses many full, detailed drawings of hands in action, which is another reason the book is so long. Fortunately, the Wikipedia presents a notation that can radically compress Chisenbop diagrams on the page, as shown in Table 4-2.²

Tip

I added a couple of symbols to the notation myself for this book (^ and v, which are described in Table 4-2).

Table 4-2. Chisenbop notation

Notation	Meaning
-	A thumb in the air
@	A thumb with its tip pressed to the table
.	A finger in the air
o	A finger with its tip pressed to the table
^	Lift that finger
v	Press that finger down

You can combine the finger notation across two hands, as shown in the examples in Table 4-3.

Table 4-3. Examples of Chisenbop notation

Notation	Meaning
....- -....	Both hands ...