Aristotle’s argument in Nicomachean Ethics 6 for the mutual implication of the virtues by one another is developed, and others added to it, in a repertory of arguments for this thesis in section 18 of the De anima libri mantissa (Supplement to the Book On the Soul) attributed to Alexander of Aphrodisias. The last part of this is echoed in no.22 of the Ethical Problems attributed to Alexander; nos. 8 and 28 of the same collection are also relevant. A distinction can be drawn between the mutual implication of the virtues and the unity of virtue in some stronger sense; the arguments in the texts attributed to Alexander are examined to see whether they imply the latter more clearly than Aristotle’s own argument does, and the conclusion is drawn that some do so because of the use they make of the conception of the noble as the goal of virtuous action, or of virtue as a whole of parts. The treatment of Aristotle’s argument in the Byzantine commentaries is characterised by a preoccupation with the special status of practical wisdom.