Cousin Ricky <ric### [at] yahoocom> wrote:

>
> -2 x  3 = -6
> -2 x  2 = -4
> -2 x  1 = -2
> -2 x  0 =  0
> -2 x -1 =  2
> -2 x -2 =  4
> -2 x -3 =  6
>
> Seems intuitive enough.  I figured this out on my own as a kid, although
> I was suspicious of my own reasoning until it was confirmed in math class.

Hmm. But doesn't the intuitive nature of your construction depend on an implicit
*assumption* that the numerical results should simply go from negative to
positive (in the descending order of your example)? In other words: that the
result of -2 X -2 being positive should *be* positive simply because -2 X 2 was
negative? (or, that -2 X -2 should simply be 'different' from -2 X 2?) Or was it
the middle column of positive-to-negative values that gave you the clue?

I think my own (flawed!) intuition when *I* was a kid would have been that -2 X
-2 would have equaled -4 !  :-O  Thankfully, my smarter teachers prevailed. ;-)

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