(Latin: persona, mask)
A complete individual rational or intelligent nature, distinct from, and incommunicable to, every other being, so that it exists and acts "of its own right" (sui juris), autonomously, independently of every other being except the Creator.
Briefly it is a rational or intelligent individual.
The attributes and actions of an intellective nature are always referred to the person present.
This person is not communicable ''as an accident" since it is a substance - not ''as a universal" to individuals since it is itself an individual - not ''as an integral part" to a whole, as a foot or hand to the whole body, nor ''as an essential part" to the whole as the body or the soul to the composite, since it is itself "complete" - nor can it be communicated to, or assumed by, a higher person by which it would be controlled and to which its actions would be referred, since it has a perfection giving it its "own proper independent existence" called subsistence.
The latter perfection by which a complete individual rational nature is rendered incommunicable to another being and hence a person according to the common opinion of Scholastics is some positive perfection, really distinct from the complete individual nature.
By many it is considered to be a "substantial mode" perfecting the nature in the line of substance and rendering it independent and incapable of being communicated to or assumed by another.
Since the human nature of Christ was communicated to or assumed by the Second Person of the Blessed Trinity, there was no human person in Christ, only the one Divine Person.
To this Person were referred all the acts of Christ's human nature.
There are three persons in God, the Father, the Son, and the Holy Ghost, really distinct as persons although possessing the same nature.
Personality in the Trinity is based on the "opposition" of the relative perfections, which are founded on the Son's having been "generated" and on the Holy Ghost's having "proceeded" from the Father and the Son.
The Divine Substance or Essence as such is not a person, since it is communicated to the three Divine Persons.
That substantial permanent being which is the subject of, and to which are referred, all the states and acts of an intellective being.
It is that which is understood by the "I," the "self."
It remains numerically and essentially the same throughout life, differing at various times only in accidents, in super-added states or acts.
Since the sensations of "seeing," "hearing," etc." modify the "self," personality consists of body as well as soul; Personality in this sense is a particular view of the Scholastic "person."
Personality (as a perfection) differs from individuality.
Individuality is that perfection by which a being is rendered unique, distinctive, and separate from others, incapable of being duplicated into another of that same being.
It is possessed by inanimate objects, by plants, and by animals, as well as by men.
Personality, however, is that perfection by which a being has control, control of self and of others through self, is free and independent, and superior to material forces, dominates instead of being dominated.
Hence it is possessed only by beings with a spiritual principle.
One could possess great individuality through remarkable "uniqueness" and distinctiveness and yet have little personality, due to his dependence and inability to control himself and others.
Most moderns place personality in self-consciousness or in freedom or in some act.
Self-consciousness "manifests" the personality but does not constitute it.
Consciousness is the modification of some thing, which thing is the self, the person or the personality.
Likewise there must be some being which is free and which acts, and that being is the person.
New Catholic Dictionary