The same design decision is in most languages that implement Common Lisp/Scheme-style numeric tower (eg. have rationals as core type). You do basic arithmetic o

The same design decision is in most languages that implement Common Lisp/Scheme-style numeric tower (eg. have rationals as core type). You do basic arithmetic on rationals or integers, you get rational or integer. You do transcendental function on pretty much anything, you get float. Also usually you also get stuff like complex rationals, which makes the rules somewhat convoluted, but that is no that relevant for this discussion.