Ars Notoria is a book of King Solomon, which he allegedly wrote through the word of God. The one who would succeed in mastering Ars Notoria would get strange power, good memory and all that ordinary mortals cannot possess.
Her learning was carried out through meditation and pronouncing prayers written in it.
However, the book is not at all harmless, on the contrary, it turned out very dangerous. One of the few who defeated Ars Notoria, Monk John from Morignya, instead of strange power, received nightmares, visions of demons and obsession. He barely healed and returned to normal.
He later wrote a book "Libor Vison" in which he gives the biggest advice that Ars Notorie should be stayed.