Canto XIX Dante has a dream of the siren, who lured sailors to destruction. A woman intervenes, calling to Virgil who unmasks the siren. Virgil wakes Dante, and they proceed to the pass up to the next cornice. Here the avaricious lie, their backs to heaven. Dante speaks with one, the soul of Pope Adrian V.

On the three remaining cornices of Purgatory are purged the sins arising from disordered love-proper. On the lower terraces the sins result from a negative self-love, or from inadequate zeal in love. From now on our concern is with loves of objects, good in themselves, but for which our loves need to be ordered and restrained. As Dorothy Sayers says in her commentary, the objects of these disordered loves are not bad in themselves, so the siren cannot be an image of them. Rather she represents the object of a distorted self-love: the image of ourselves as somehow completed by the wealth or pleasure that we might pursue. It is this that lies at the root of disorder in our loves.

The woman who intervenes can be thought of as an image of virtue, a tendency or disposition to a proper ordering of our capacities. Virtue calls on reason (of which Virgil is the figure throughout Dante's poem), and he unmasks the siren. In short, by properly trained dispositions, we are able to see the reality of our situation. Wealth, for example, will not complete our happiness, which only God can fulfil; and when we exercise reason we see how avaricious pursuit of wealth could undo other goods (justice, for example) which we should pursue. Virtue, however, must be enlivened by Charity, if it is to be effective, so an account of the good life in the purely psychological terms of Dante's dream is not entirely satisfactory.

Dante's dream of the siren

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