The paper set up a small \u201cphilosophical lab\u201d for thought experiments using Digital Universes as its main tool. Digital Universes allow us to examine how mereology affects the debate on New Realism of Ferraris (2012) and shed new light on the whole notion of Realism. The semi-formal framework provides a convenient way to model the varieties of realism that are important for the program of New Realism: we then draw the natural consequences of this approach into the ontology of our world (may it be digital or not), arguing that the same considerations that apply to Digital Universe would hold for chess, institutions and social objects as well. Once a particular version of mereology is chosen, there are unavoidable consequences that t...