Overloading + could be magic if you want it to be. In go, + is exactly what you think it is. In languages with operator overloading, I literally could make + do whatever I wanted to.
Just like you can make a function do something totally unrelated to how it is called, do what it is actually in the name, wipe out the hard drive, launch missiles, whatever.
A concept used in lambda calculus, introduced in computing since Lisp exists.
Also part of abstract mathematics field, where operator symbols get defined for the proofs.