Reducing Programs to Objects

C++, Java, C#, Python, Ruby, JavaScript are the most powerful object-oriented programming languages, if language power would be defined as the number of features available for a programmer. EO, on the other hand, is an object-oriented programming language with a reduced set of features: it has nothing by objects and mechanisms of their composition and decoration. We are trying to answer the following research question: "Which known features are possible to implement using only objects?"