Posse eligere malum, non est de ratione liberi arbitrii; sed consequitur liberum arbitrium, secundum quod est in natura creata possibili ad defectum.
"To be able to choose evil is not intrinsic to the concept of free will; but it follows from a free will insofar as it is in a created nature capable of failing."
De Veritate q. 24 art 3 ad 2
