 One way to formalize the interaction between probability and qualitative uncertainty is by adding another relation to the model and a modal operator to the language as is done in Fagin and Halpern (1988, 1994). Formally, we add to a basic finite probability model a relation \(R\subseteq W^2\). Then we add to the language a modal operator \(\Box\), such that \((M,w)\models \Box\phi\) if and only if \((M,w')\models \phi\) whenever \(w R w'\).