Dante defined lust as the disordered love for individuals. It is generally thought to be the least serious capital sin, as it is an abuse of a faculty that humans share with animals and sins of the flesh are less grievous than spiritual sins. In Dante's Purgatorio, the penitent walks within flames to purge himself of lustful thoughts and feelings. Unforgiven souls guilty of lust are also eternally blown about in restless hurricane-like winds symbolic of their own lack of self-control of their lustful passions in earthly life.