And on the Lunacy of Negatives

[teresaq]

And for a laugh.

Negative Numbers Aren’t That Real

Let’s think about numbers a bit more. The example above shows our number system is one of many ways to solve the “counting” problem.

...

Even then, negative numbers may not exist in the way we think, as you convince me here:

You: Negative numbers are a great idea, but don’t inherently exist. It’s a label we apply to a concept.

Me: Sure they do.

You: Ok, show me -3 cows.

Me: Well, um… assume you’re a farmer, and you lost 3 cows.

You: Ok, you have zero cows.

Me: No, I mean, you gave 3 cows to a friend.

You: Ok, he has 3 cows and you have zero.

Me: No, I mean, he’s going to give them back someday. He owes you.

You: Ah. So the actual number I have (-3 or 0) depends on whether I think he’ll pay me back. I didn’t realize my opinion changed how counting worked. In my world, I had zero the whole time.

Me: Sigh. It’s not like that. When he gives you the cows back, you go from -3 to 3.

You: Ok, so he returns 3 cows and we jump 6, from -3 to 3? Any other new arithmetic I should be aware of? What does sqrt(-17) cows look like?

Me: Get out.

 

http://betterexplained.com/articles/how-to-develop-a-mindset-for-math/