 (4) is not a change at all, because not-A and not-B are neither contrary nor contradictory. (2) is passing-away and (3) is coming-to-be, and these two changes are not motion. The only change that is a motion is (1) from positive A to positive B. Averroes interprets A (the Latin translation reads subjectum) as ‘being’ (esse), and non subjectum becomes ‘non-being’ (non esse), but immediately he adds: