However, Judah ha-Levi is against limiting philosophical speculation to matters concerning creation and God; he follows the Greek philosophers in examining the creation of the material world. Thus he admits that every being is made up of matter and form. The movement of the spheres formed the sphere of the elements, from the fusion of which all beings were created. This fusion, which varied according to climate, gave to matter the potentiality to receive from God a variety of forms, from the mineral, which is the lowest in the scale of creation, to man, who is the highest because of his possessing, in addition to the qualities of the mineral, vegetable, and animal, a hylic intellect which is influenced by the active intellect. This hylic intellect, which forms the rational soul, is a spiritual substance and not an accident, and is therefore imperishable.