A feasibility relation for preorder \(X\) given preorder \(Y\)
A monotone map \(X^{op}\times Y \xrightarrow{\phi} \mathbf{Bool}\)
Also denoted \(X \overset{\phi}\nrightarrow Y\)
Given \(x \in X, y \in Y\), if \(\phi(x,y)=true\) then we say x can be obtained from y