In the medieval poem, Dante's 'Divina Commedia', we find a form of self-knowledge that is based on a certain clairvoyance. The teacher of Dante was Brunetto Latini. Dante meets him in Inferno... It is not clear, why he is burning in Inferno.
Rudolf Steiner has spoken about Latini in several lectures. According to his occult investigations, Brunetto Latini became a sunstroke as he was coming back to Florence. The stroke gave him a vision of the true spiritual world behind nature; he became teachings from a goddess, the goddess 'Natura'. She showed him the path to the clairvoyance.
Before this time there was a spiritual movement in Chartres, the 'School of Chartres'. The great teachers here (Alanus ab Insulis is the most famous teacher) actually experienced how Natura vanished from the human conscience, which meant that the spiritual vision of nature became more and more impossible. In Brunetto Latini a last glance of Natura was caught... And he taught his pupil Dante this. So we can see a telling about the spiritual world in the Divina Commedia, in a last glance. The time of the scholastics was already there and after that the development of natural science was emerging. In this science we have no spirit anymore; it is the intellect that has to strive for knowledge, by perception and experiment.
In the visions of Latini and Dante we find a self-knowledge that occurs as imaginations in a visionary way. They appear in a way like they are coming from the outward. The visionary is seeing the images as in a dream. When we study the seven sins, we find a self-knowledge by recognizing these sins as parts of ourselves. But we can also deny them and say that we don't have them at all.
In modern times self-knowledge should become a different one. The position of the self should be turned over completely. The spiritual mind doesn't look from itself into its surroundings anymore. It should take a position outside himself and view back to the self. In this self the spiritual world will reveal itself. So it is not like the normal consciousness. Here we find ourselves in the centre, and the world in the surroundings. In the modern initiation it is the other way around: The self in the surrounding looks at the centre, and the centre is permeated by the spiritual world.
But before that can be, the self has to purify itself from all selfishness in thinking, feeling and in the will. Here is the point where the modern doctrine of sin would start. It would not have to be taught by a teacher or a priest or an initiated. It would show itself in the truthful perception of the self by the self.
The classic question of Socrates: Can virtue be taught? finds its answer here. Yes, virtue can be taught. It can be taught in the truthful perception of the self by the self. This self-knowledge is so real, that it bears in it the germ of self-transformation. This self-transformation is not a following of doctrines, but a living transformative process.
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Canto XV, meeting with Brunetto Latini in Inferno, Gustav Doré
Modern spiritual self-knowledge by Mieke Mosmuller