Worldbuilding

yinrih are arboreal quadrupeds with six digits on each of their four paws,for a total of 24 digits. All four paws are used more or less equally for locomotion and manipulation. The two systems (base 12 and base 24) reflect the divide between surface dwellers and spacers. Surface dwellers have to rear up on their hind feet to use their forepaws, and their rear paws have to bear their weight, giving them 12 digits to count with. Spacers live perpetually in zero-G, freeing up all 24 digits. This is reflected in language. Commonthroat is spoken in the Allied Worlds, with a large proportion of the population being surface dwellers, so it uses a base 12 system. Moonlitter and Partisan Territory occupy the outer reaches of the solar system and have a larger proportion of spacers, so Outlander, the local language, uses a base 24 system.