which doesn��t look quite right. My opinion is that all of the #includesBehavior: calls should return true. I��m not so sure about the #isKindOf: If we continue on that road the single class inheritance won��t be central to all of the code but a special quality. One of the composed elements can be a class with a superclass hierarchy. I don��t know if there is a rationale that #includesBehavior: and #isKindOf: refer to that the same thing or not.

It would be good to take the opportunity to make this a concept which gives back some symmetry again.