How to Count to Ten on One Hand

I showed this to my friend the other day, nonchalantly, and he was blown away! Wait, what?! I thought everybody knew this!

Count “One” on Your Thumb

The secret to counting to ten on one hand — that’s a full count of five beyond where your fingers run out — is a binary system! No, really, people think of binary as complex, or limited, or anything but useful, but it really can hold information much more densely than simply counting on your fingers!

Start out by counting “one” on your first available digit. Because the middle, ring, and pinky fingers are linked together in biologically complex ways, it is much easier to articulate the thumb and index fingers … so it’s best to start counting with your thumb.

How to Count

Count “one” on the thumb. The thumb will be the first place in the binary system, and it indicates a value of “one” or “zero.” In fact, all counting in this binary system is a matter of toggling the thumb on or off and tallying up the cumulative results on the rest of the fingers on that onehand.

I count one on the thumb. For two, the thumb goes back down, and the index finger comes out. For three, the thumb comes back out again, leaving the index finger out as well. For four, the thumb goes back down, the index finger goes down and the middle finger comes up. (Yes, in some cultures this can be a rude gesture, so I typically make my thumb come out a bit to meet or almost meet the tip of the other wise offensive finger.) Then the thumb comes out again for five.

See how you have already reached five? And with only three fingers involved! For six, the thumb goes back down (for zero and every even number, the thumb is down; for all odd numbers, the thumb is up) and the forefinger comes out again. For seven, the thumb comes out again so that the thumb, index, and middle fingers are all up. For eight, all these fingers go back down, and the ring finger comes up. Now, since I am generally only counting to ten with this one hand, I usually use a trick and instead of the ring finger, which as mentioned before is hard to articulate, I use the pinky finger for eight. Then for nine, the thumb comes up, and for ten, the thumb goes down and the index finger comes back up. (In practice, I just leave the thumb out when I am done, and this has the added benefit of forming the “I Love You” sign in ASL.)

Originally I formulated this (I am not claiming to be the first one to do so) for counting while driving, so one of the neat benefits of this counting system is that at least two fingers can maintain a firm grip on the steering wheel at all times while still accurately counting and holding your place.

That’s it! I hope this enhances your life.

Counting from “One” to “Ten” on One Hand

Q&A

How high can you count on one hand with a binary system?

This is a great question. If you fully utilize all fingers for all values, instead of using the shortcuts I highlighted earlier, you can count up to thirty-one. However, because of the physical constraints of the hand system, it does take some training and practice to count that high reliably.

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