How do I get the public methods of a class without inherited methods?

Given any object I can call #public_methods and see all the methods it will respond to. However, I find it would sometimes be handy to get a quick list of all the public methods that are not inherited, i.e. the stuff that's really part of this class.

I found in "Easy way to list public methods for a Ruby object" that if I use:

(Foo.public_methods - Object.public_methods).sort

I can filter out a lot of basic Ruby stuff. I'd like to be able to filter everything that was inherited all the way up the chain. If I know the parent class I can filter using it, but I'd like to come up with a generic command that could return an array of the uninherited public methods for any object.