Abstract
In _De Spiritualitate et Immortalitate Animae Humanae Scotus distinguishes three senses of 'immaterial': x is immaterial if x depends upon nothing material, x is immaterial if x is unextended, x is immaterial if x is abstract. Pace Scotus: depending on nothing material is neither necessary nor sufficient for being immaterial, being unextended is not necessary but is sufficient for being immaterial, and being abstract is not necessary but is sufficient for being immaterial. The idea of immaterial existence is not incoherent. God, the soul, numbers and universals can exist without a physical universe