Final answer:
The group not included in Dante's Inferno's circle of limbo is indecisive people who were morally ambiguous. Limbo houses virtuous pagans, unbaptized infants, and virtuous individuals who lived before Christ.
Step-by-step explanation:
In Dante's Inferno, the group not included in the circle of limbo is the indecisive people who were morally ambiguous. Limbo is the first circle of Hell in Dante's Inferno, which holds souls that did not commit active sin but were not affiliated with Christianity due to being born before Christ's advent or dying unbaptized as infants.
Therefore, the virtuous pagans, unbaptized children, and even virtuous individuals who lived before Christ, such as esteemed pagan musicians and poets, are all allocated to the limbo section of the afterlife according to Dante's vision.