It is well known how often psychiatric patients report religious experiences. These are especially frequent in schizophrenic and epileptic patients as the subject of their delusions. The question we pose is: are there differences between this kind of religious experiences and those we find in religious texts or in the mythological tradition?

If Cicero's Republic and Agustine's City of God are studied in parallel, and the Somnium Scipionis is specifically compared to De civitate Dei XXII, and the theme of the souls' immortality and of justice is also examined, it seems possible to show that Cicero's Republic contributed decisively to the general design of the City of God. Both republics, moreover, in a more general way, share with Plato's Republic certain common characteristics that are here pointed out.