> This is silly.

Oh my bad, great counterpoint.

> The semantics are entirely different!

They're not. A symbol is an arbitrary identifier, which can be used to point to system elements (e.g. classes, methods, etc...). These are all things you can do just fine with immutable interned strings. Which is exactly what languages which have immutable interned strings do.

You'd just have a broken VM if you used mutable strings for metaprogramming in Ruby, so it needs symbols. Both things it inherited from all of Perl, Smalltalk, and Lisp.