 Averroes blames Avempace for misunderstanding the essence of velocity. Velocity is not a motion added to or subtracted from another motion, in this case, natural motion, “like a line added or subtracted from a line” (LC 161A). For Averroes, there is a ratio between the power of mover and the resistance of the movable, and a ratio between the hindering and the hindered, and velocity depends on both factors. Velocity in the celestial spheres results from the first kind of ratio, since there is no medium, and Averroes agrees with Avempace in considering the degree of nobleness (sharf) of the various spheres as the factor explaining their different velocities. Sharf is the surplus of “energy” between the power of motor and the resistance opposed by the movable.