How to count to 255 on your fingers (and not even use your thumbs!)

Thanks Debbie for inviting me to do a guest blog.

My lovely assistant is my daughter Abby. Let’s start with one.

Easy. Now for two.

Abby didn't want to do this one, because she is a good girl, and this looks like a rude gesture. But in the name of science, and for her daddy, she consented. On to three.

Yeah...peace brother. Here’s the first trick. If your index finger is up then you know it is an odd number. Now for four, five, six and seven.

I admit that some of these, especially the number four, feel unnatural, but so does playing the violin when you are beginning to learn. On to eight.

Now for the second trick. Go back and look at 1, 2, and 4. Notice how each time we raise another single finger to the left the number doubles. Now let's get Abby's other hand involved and double again.

You've got the hang of it now I bet. Let’s go ahead and raise each successive finger in turn to double to 32, 64 and then 128.

Now let’s do some addition. What is 7 + 8? Let’s count it on our fingers.

See what Abby did there? The first three fingers (7) plus the pinky (8) is equal to all four fingers together (15). That’s right—she just added 8 + 7 on one hand! Abby is beating the old ten finger counting system by 5 and she's not even using her thumb. And adding her other hand doesn’t merely double her counting capability...the results are exponential.

Let’s do more addition to prove it.

That’s 15+16+32+64+128=255! (Use your calculator if necessary.)

You’re counting in binary, baby. Your digits have gone digital! This is how computers think. In the computer world each of your fingers is a bit, four fingers are a nibble, and all eight of your fingers together represent a byte. When your USB drive says it has 1 Gigabyte it can store, that means it has the equivalent of 8,000,000,000 fingers available (approximately) to store your data.

I hope you’ll practice this and maybe even learn to use it. But be careful in public—someone might get the wrong idea when you show them the number two.

It's been a pleasure doing the guest blog and I hope I'll be invited back some day. 

Stephen.