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15/01/08 : "Can we have your liver then?"

Searching for something to help Rosie (and Sarah!) get a better understanding of big numbers - something most people don't seem to "get" - I found this video on YouTube. It's about thirty years old and slightly inaccurate in places, but illustrates nicely how much difference adding another zero makes (reminds me of a maths teacher I once had whose favourite expression was "bung a nought in!").

If the increase in distance that the camera pulls back each time doesn't seem like a big deal to you, think of the return journey, where each step is 90% of the total distance back.

Makes you feel so, sort of, insignificant, doesn't it?

The other thing most people don't seem to have a grasp of is probability. I'm sure this is the reason why so many people believe in gods and other ridiculous things - something happens that is unexpected or an amazing co-incidence and obviously that proves that it's fate, or god did it or something. I once had a friend who couldn't grasp the simple concept that the chances of the four-digit combination on his bike lock being, say, 1 2 3 4 were the same (1 in 9999) as them being 3768 or any other four digit number. Luckily he didn't have anything with a three digit combination which turned out to be 666 because that would obviously have been "a sign".

UPDATE: a similar but more up to date video can be found here.

UPDATE 2: I am ashamed to discover that Sarah didn't get the liver/insignificant reference. Explanation here.