 On the other hand, suppose that every instance in \(\mathbf{C}\) verifies some relation between types that happen to be counterparts of types from \(\mathbf{A}\) and \(\mathbf{B}\). Then such relation captures a constraint on how the parts of the system are correlated. In the radar example, the theory of the core classification MonitSit will include constraints such as PlainMovingNorth \(\Rightarrow\) DotGoingUp. This regularity of monitoring situations, which act as connections between radar screen-shots and planes, reveals a way in which radar screens and monitored planes correlate with each other. All this affords the following version of information transfer. 