Prototype is a typeface with a very contemporary identity crisis—is it old or new, uppercase or lowercase, serif or sans-serif? Prototype tries to be all things to all people.
There have been many attempts at creating a universal typeface, one that rationalises the alphabet and removes the inconsistencies of upper and lower case, illogically implementing a logic to something that has grown organically and is perfectly usable. Prototype was the same experiment carried out at a time when design was experiencing an identity crisis is of its own—letterforms that try to be all things to all people but end up being something else entirely.