 Let \(t\) and \(b\) be the designated values. These are the values that are preserved in valid inferences. If we define a consequence relation in terms of preservation of these designated values, then we have the paraconsistent logic LP (Priest 1979). In LP, ECQ is invalid. To see this, we assign \(b\) to \(p\) and \(f\) to \(q\). Then \(\neg p\) is also evaluated as \(b\) and so both \(p\) and \(\neg p\) are designated. Yet \(q\) is not evaluated as having a designated value. Hence ECQ is invalid in LP.