 Definition 3.6  A system of agents’ beliefs \(\boldsymbol{\mu}^*\) is a Nash equilibrium if, and only if,   condition (3.iii) is satisfied, For each \(k \in N, \mu_k^*\) satisfies probabilistic independence, and For each \(s_{kj} \in s_k\), if \(i, l \ne k\) then \(\mu_i^*(s_{kj}) = \mu_l^*(s_{kj})\).  