In the philosophical tradition the soul (anima) is the life-principle of a living being — that which makes the body alive and forms it into a unified, self-organizing whole. In the plant it is the vegetative life-principle (growth, nutrition, reproduction); in the animal, sensation is added. In the human being, however, the soul is a spiritual soul: a spiritual life-principle that informs and animates the entire body and that fundamentally transcends everything merely animal.
The human spiritual soul is not a “souped-up” animal soul. It is not an additional intellect set upon an animal base, but a single spiritual life-principle. The vegetative and sensitive functions — growth, digestion, sensation, movement — are contained and sublated within it. They do not form separate strata but aspects of a single principle. Just as the oak does not have the acorn alongside itself but has taken it up and surpassed it within itself, so the human spiritual soul has taken up and surpassed the vegetative and the sensitive within itself (cf. Bexten 2017, pp. 150—165).
The spiritual soul is the essential form of the human being: the sufficient ground of its unity and identity. Without it the body disintegrates — not because someone destroys it, but because nothing is left that holds it together.
This spiritual life-principle is present as soon as the human being is present — that is, from the fusion of the germ cells. It is not measurable, not weighable, not visible under the microscope. Yet it is the most real and deepest thing in the human being, the ground of its personhood. The body-soul unity is therein no external joining-together, but an interior, inseparable unity.
Chapter assignment: Chapter 4: What is human personhood? (esp. 4.3.2, 4.6.4)
Sources: Generated by querying the Personhood ontology.
Further sources:
- Thomas Aquinas, Summa Theologiae I, qq. 75—76 (the spiritual soul as forma corporis)
- Aristotle, De anima II, 1—3 (the soul as life-principle and essential form of the body)