Why 10 isn't really a number...

I've mentioned before that the way we count is really down to the way we're made - we count in tens because we have ten digits.  If the Good Lord had created us like the Simpsons, with a thumb and three fingers on each hand, we would count in eights (by the way, did you know that the only character in the Simpsons with a full complement of fingers is God himself?), so counting, Simpsons-style would go 1, 2, 3, 4, 5, 6, 7 - and then what?  No, not 8 - it would be 10.  Just as, counting in tens as we do, there are (ignoring zero) only 9 digits, so in eights, there are only 7.  10 is not really a number, it simply represents one of whatever base we are counting in plus 0.  So in binary (base 2) 10 is 2 in decimal.  In hexadecimal (base 16) 10 is 16 in decimal. And in octal (base 8 - the Simpsons way) 10 is 8 in decimal.  So 10 represents a concept - not a fixed number.