The non-stat component of the Attribute Willpower, the Mage’s Will is their ability to impose their desires and goals upon the world itself. The Mage’s Will confronts reality and it is reality that has no choice but to obey.
To cast a spell, she imagines the effect she desires, focuses her mind on the symbols of her Path that will create that effect (the Imago), and through the medium of her Gnosis makes the world obey. Magical properties that were only theoretical override what’s “real,” and the universe changes.
Magic is an extraordinarily useful tool for the observation and analysis of the Mysteries. Virtually all phenomena in the Fallen World can be observed and described by one or more Arcana.
Mages largely agree that the rare exceptions are subjects that hail from Realms that are completely alien to human thought — including The Abyss. The Wise likewise recognize that not all Mysteries are the result of Awakened magic — no more than the motion of the sea is caused by the existence of thermometers or barometers.