Metaphysical knowledge essentially implies permanent and changeless certitude. Like Parmenides, he argued that reality is ungenerated, indestructible, indivisible, changeless, and motionless. It is detached from outer self and inner self, it is all pervading, pure, changeless. Galileo used its brief appearance to counter the Aristotelian dogma that the heavens are changeless. Changeless is a steampunk paranormal romance novel by Gail Carriger.