Re: Why a kilogram?
When I was at school in the 60s, we were taught to use both the Imperial and the cgs (centimetre, gram and second) system. cgs: Inconsistent length versus inconsistent mass in SI. Our Science teachers advised us that SI (and global warming) was coming. My engineer father used to use slugs and poundals in his caculations. I have no idea what system they belonged to. SI was an easy to transition after cgs.