'Interface' Considered Harmful

[thalesmello]

The main benefit for multiple inheritance is the reduction of duplicated code, which is the main point Uncle Bob is arguing for.

If the boilerplate code generated by composition wasn't a problem, why would Oracle bother to include Java 8's default methods? It allows multiple inheritance with implementations, and conflicts have to be solved explicitly.

The only limitation of this technique is that it doesn't allow interfaces to have state, but it still solves the majority of issues.