 The question thus arises as to how one can distinguish powers as parts from both subjective and integral parts. Here we will look briefly at only one account. Aquinas separates potential wholes from both universals and integral wholes by considering two parameters: the presence of the whole in the part with respect to the whole’s essence, and the presence of the whole in the part with respect to the whole’s power (Summa Theologiae I, q. 77, art. 1, ad 1). The universal whole “is present to each of its parts in its entire essence and power”. It is for this reason that each part of the universal is a subjective part. In contrast, the integral whole is not in each of its parts either in respect to its entire essence or in respect to its power. Hence, the integral whole is not predicable of any one of its parts taken singularly. Finally, the potential whole is present to each of its parts with respect to its entire essence, but not with respect to its full power. This is why, even though one’s soul is non-composite and cannot be cut up, the operation of thinking does not entail along with it the operation of sensing. 