18 years threshold is just an odd convention. Biologically it's closer to 12 but the legal and cultural threshold varies wildly all over the planet. My rule of

18 years threshold is just an odd convention. Biologically it's closer to 12 but the legal and cultural threshold varies wildly all over the planet. My rule of thumb: if you don't have to make a living - you're a kid. Enjoy it while it lasts.