How did Aquinas defend the immortality of the human soul while using Aristotle’s ideas about body and soul?

St. Thomas Aquinas defended the immortality of the human soul by adapting Aristotle’s hylomorphic theory—which posits that the soul is the "form" of the body—while modifying it to align with Christian doctrine.12

While Aristotle generally viewed the soul as inseparable from the body’s matter, Aquinas argued that the human soul is a "substantial form" that possesses a unique status. He maintained that because the human soul is a spiritual entity capable of intellectual activity, it is not entirely dependent on matter for its existence.324

Aquinas’s defense rests on the following points:
* Subsistence: Unlike the souls of other living beings, the human soul is a "unique subsistent form," meaning it has an existence of its own that allows it to survive the dissolution of the body.32
* Immateriality: Because the soul possesses no matter and lacks substantial parts, it cannot be corrupted or disintegrated upon the death of the physical organism.4
* Distinction from Matter: Aquinas held that while the soul is substantially united with the body to constitute human nature, its capacity for reason and will demonstrates that it is not merely a material function.32

By defining the soul as a subsistent form, Aquinas reconciled Aristotelian philosophy with the belief in individual immortality, rejecting the view that the soul is a mortal entity that perishes with the body.135