 The number \(\varrho(A)\) represents the agent’s degree of disbelief in the proposition \(A\). If \(\varrho(A) \gt 0\), the agent disbelieves \(A\) to a positive degree. Therefore, on pain of inconsistency, she cannot also disbelieve \(\neg A\) to a positive degree. In other words, for every proposition \(A\) in \(\mathbf{A}\), at least one of \(A, \neg A\) has to be assigned rank 0. If \(\varrho(A) = 0\), the agent does not disbelieve \(A\) to a positive degree. However, this does not mean that she believes \(A\) to a positive degree \(-\) the agent may suspend judgment and assign rank 0 to both \(A\) and \(\neg A\). So belief in a proposition is characterized by disbelief in its negation.