ANGEL in philosophy (Greek: αγγελος [angelos], Latin: angelus—messenger, envoy, mediator)—the concept basically appears in the Bible (the Hebrew equivalent of “angel”—mal’akhi) and it refers to a being between God and man and so an angel is regarded as a spirit. The function of an angel is to be God’s messenger to men and to announce God’s Revelation. A similar understanding may be found in various religions and in different philosophical traditions.
In Greek thought we find mention of demons (δαιμονες [daimones]). Aristotle writes of Thales’ view that the world is full of gods. Diogenes Laertios adds that the Pythagoreans thought that the air is full of souls that are called demons or heros and who send dreams to men. Democritus also spoke of deities that dwell in the air. Plato in his dialogues writes of demons that serve God, help men, and are between the two worlds (Symposium, Timaeus, 40 A–B); among divine beings he mentioned fixed stars that are living, eternal, and revolve with a uniform and identical motion. Aristotle thought that there are beings in the heavens—the sphere of fixed stars—which do not grow old or change, are not influenced by anything, and which enjoy the most pleasant and independent life for all eternity (De Caelo, I 279 a). According to Plotinus, the heavenly bodies are the abode of the purest and most perfect spirits which are visible to the lower spiritual beings directly beneath them. They behold deities and are an incarnation of pure spirit. In the sphere of air close to the planets dwell the demons who are eternal beings and behold the superterrestrial world, but they are joined with matter and have fiery and ethereal bodies. Porphyry was the first philosopher to develop a doctrine concerning the essence and role of angels. Like Plotinus, Porphyry said that demons are beings that emanate from the soul of the world. They dwell under the moon and rule their own spiritual domain. The good demons rule this domain but they allow the evil demons to manage it. The good demons bring the prayers of men to God and defend men, while the evil demons try to ensnare human souls in matter. Iamblichus developed Porphyry’s doctrine and divided the demons into four groups: angels who lift men out of matter; archangels who carry the soul to heaven; demons (good or evil, depending on the gifts they impart to men) who bring souls close to matter; and heros who direct the affairs of the world. After souls come forth from the soul of the world they desire to reconnect with the deity, and a personal demon helps the soul achieve its desire. Proclus distinguished five categories of demons differing in perfections and possessing different functions and powers. The more perfect souls are subject to higher demons who guide and protect them.
The doctrine of angels also refers to Gnosticism. According to gnostic doctrine, there are, besides demiurges and aeons, beings between the god and man. Gnosticism typically introduced many names of angels and different deities and held that the world and man were created by angels.
Patristic thought refers to Origen’s views on angels. Origen adopted neo-Platonic cosmology and theory of angels (On principles). Origen distinguishes three categories of spiritual natures: spirits who chose the good but need restitution—the angels; spirits who inhabit material bodies as a penalty for sin—human souls; and spirits who remain disobedient to God—demons (evil spirits). The hierarchy of spirits is based on their respective proximity to matter—angels have an individual life and bodies of very subtle matter. Angels are divided into orders or ranks, each having its own domain of action. According to their merits or faults the angels are assigned to higher or lower ranks. Each man in his struggle to be set free from matter has his good angel and his evil angel. Western patristic literature generally accepts a certain corporeal aspect in the angel’s nature. The Greek Fathers try to restore the teaching that angels have a spiritual nature. Pseudo-Dionysius Areopagite’s On the celestial hierarchy had particular influence on the scholastic doctrine of angels. In his meditations on angels, Pseudo-Dionysius uses the conception of an hierarchy (which is a “holy order and knowledge, and an activity that makes one similar, insofar as possible, to the Divinity” De coelesti hierarchia III 1). The hierarchy is closely connected with the neo-Platonic theory of emanation. Pseudo-Dionysius identifies biblical angels with pure spirits who shared in the divine light and love, and by contemplation became similar to their divine model. They live a perfectly intellectual life. He also follows Proclus (Elements of Theology) and distinguishes three hierarchies of angels. Each hierarchy is composed of three choruses (Seraphim, Cherubim, Thrones; Dominations, Powers, Authorities; Principalities, Archangels, Angels).
Scholastic thought (including that of Anselm of Canterbury, Peter Lombard, Bonaventure, Albert the Great, Thomas Aquinas, Duns Scotus, and Suarez) developed in greater depth the theory of the nature, knowledge, and will of the angels. They analyzed the following questions: the incorporeality of angels; whether angels are composed of matter and form; their indestructibility; differences between angels; the hierarchy of angels; their number; the relation of an angel to a material body and to location; the motion of angels, the mode and object of an angel’s knowledge; their freedom of will and acts of love; and the sins and merits of angels. According to Thomas Aquinas (De substantiis separatis; S. th., I, q. 50–64; C. G., II, c. 91–101; De entis, c. 4), angels are pure spirits but they can assume a body to be seen when they manifest themselves to human beings. Thomas rejects the view that in the ontological structure of an angel we can distinguish matter (as the principle of change and motion), and form (as Bonaventure holds, In II Sent., 3, 1, 1, 1); Thomas emphasizes their composition of existence and a spiritual essence. Since matter does not belong to the essence of an angel, angels differ from one another specifically (while Duns Scotus thought that differences among angels result from different functions). Thomas accepts the hierarchy of angels presented by Pseudo-Dionysius Areopagite.
St. Thomas considers the problems associated with the knowledge and free action of an angel as an intellectual substance separate from matter. St. Thomas compares these operations (as well as their objects and modes of action) to man’s acts of will and knowledge. In this way he explains the spiritual life characteristic of man. An angel’s knowledge is an accidental act (as it is in the case of man), and it intentionally perfects the angel. Yet angels are purely spiritual beings and they continually, actually, intuitively, and intellectually know the intellectual cognitive forms that are connatural (connaturales) to them. For this reason an angel does not know one thing after another nor does he make inference about one known thing on the basis of another. Unlike men, angels do not first produce the forms of sense knowledge in their concreteness and materiality. Angels do not perform abstraction. Therefore among the spiritual faculties of angels we cannot distinguish an active and passive intellect. An angel, however, is a contingent being, and is characterized by the possession of many cognitive forms as distinct from God’s mode of knowledge. An angel’s mode of knowledge is strictly connected with his place in the hierarchy. The higher an angel is positioned in the hierarchy, the fewer cognitive forms does he need to grasp intellectually knowable things. An angel knows himself through his essence. In knowing his own essence, he knows God as in a “mirror”, but does not see God’s essence.
Thomas analyzes the question of free will in angels. He says that angels, as they intellectually know happiness, themselves, and God as the cause of their nature, desire them by necessity (unlike Duns Scotus and Suarez who thought that every act of will in an angel is free). Free choice, however, is connected with the last practical judgment to which the choice is directed. An angel cannot sin directly against the natural law which he perceives in his own essence. If, however, he sins, his sin is always a mortal sin, for he intuitively knows the means to the final end and so any disorder in the means to the end is inseparable from mortal sin with respect to the final end. An angel’s mortal sin is unforgivable and irrevocable (Duns Scotus and Suarez thought differently, that an angel can repent after each mortal sin). Likewise, the good choice of the good angels is irrevocable.
Scholastic angelology had various sources—ancient philosophy, Gnosticism, Arab thought, astronomical theories concerning certain spiritual substances, and biblical thought. Contemporary thinkers and theologians still draw on scholastic thought.
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