But there would be an unintended consequence of evolving only eight fingers. Any such cartoon civilization would have an octal system of counting, or base eight. This means that the fictional worlds in which they lived would be ruled by completely different numbers than our own.
Important values would be based on powers of eight, so that the octal number ten would represent eight in decimal. 100 would be 8x8, or 64. 1,000 would be 8x8x8, or 512. This would lead to some really bizarre math for any human unfortunate enough to cross over into 2D four-fingered land, and those scores in Space Jam would make no damned sense to Jordan.
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Those important numbers would be most evident in the screwy way they would measure time. The year 2014 in our world becomes 3736 in base 8 in Toon Town, since the equivalent of a century has 64 years, and the equivalent of a millennium just 512. The base eight year 3000 happened in our base ten year of 1536, and the octal world's next millennium at the year 4000 will be coming up in our year 2048. The same amount of time will have passed; it's just represented by different digits.
Then there's the money. As Andy Kiersz of Business Insider says: "One dollar in base ten would convert over to $1.44 in base eight, and $0.84 in base twelve. Conversely, what we'd call a dollar in our world with eight fingers -- $1.00 in base eight -- would translate to just $0.64 in our base ten world." So any intra-world trading going down in Who Framed Roger Rabbit? would be fraught with the kinds of difficulties that would make our stock exchange look like an abacus.
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