Tree of virtues and tree of vices

A tree of virtues (arbor virtutum) is a diagram used in medieval Christian tradition to display the relationships between virtues, usually juxtaposed with a tree of vices (arbor vitiorum) where the vices are treated in a parallel fashion.

Together with genealogical trees, these diagrams qualify as among the earliest explicit tree-diagrams in history, emerging in the High Middle Ages.

[1] At first appearing as illustrations in certain theological tracts, the concept becomes more popular in the Late Middle Ages and is also seen in courtly manuscripts such as the psalter of Robert de Lisle (c. 1310-1340).

The nodes of the tree-diagrams are the Cardinal Virtues and the Cardinal Vices, respectively, often culminating with the Theological Virtues and Vices, each with a number of secondary virtues or secondary vices shown as leaves of the respective nodes.

[2] In this example, the trees are also further subdivided into a ternary structure, as follows: In the Italian Renaissance, Pietro Bembo developed a similar flow-chart-like "moral schema" of sins punished in Dante's Inferno and Purgatory.