New Advent
 Home   Encyclopedia   Summa   Fathers   Bible   Library 
 A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z 
New Advent
Home > Catholic Encyclopedia > I


Please help support the mission of New Advent and get the full contents of this website as an instant download. Includes the Catholic Encyclopedia, Church Fathers, Summa, Bible and more — all for only $19.99...

This list represents only a tiny fraction of articles available on the New Advent website. For a more complete list, please see the full index for I or use the search box at the top of this page.

Ichthys (Fish), Symbolism of the - The symbol itself may have been suggested by the miraculous multification of the loaves and fishes or the repast of the seven Disciples, after the Resurrection, on the shore of the Sea of Galilee, but its popularity among Christians was due principally, to the famous acrostic consisting of the initial letters of five Greek words forming the word for fish (Ichthys), which words briefly but clearly described the character of Christ and His claim to the worship of believers: Iesous Christos Theou Yios Soter, i.e. Jesus Christ, Son of God, Saviour
Iconoclasm - The name of the heresy that in the eighth and ninth centuries disturbed the peace of the Eastern Church, caused the last of the many breaches with Rome that prepared the way for the schism of Photius, and was echoed on a smaller scale in the Frankish kingdom in the West
Iconography, Christian - The science of the description, history, and interpretation of the traditional representations of God, the saints and other sacred subjects in art
Iconium - A titular see of Lycaonia
Iconostasis - A great screen or partition running from side to side of the apse or across the entire end of the church, which divides the sanctuary from the body of the church, and is built of solid materials such as stone, metal, or wood, and which reaches often (as in Russia) to the very ceiling of the church, thus completely shutting off the altar and the sanctuary from the worshipper
Idea - The word was originally Greek, but passed without change into Latin. It seems first to have meant form, shape, or appearance, whence, by an easy transition, it acquired the connotation of nature, or kind
Idealism - The characteristic of those who regard the ideas of truth and right, goodness and beauty, as standards and directive forces
Idioms, Communication of - A technical expression in the theology of the Incarnation. It means that the properties of the Divine Word can be ascribed to the man Christ, and that the properties of the man Christ can be predicated of the Word
Idiota - The nom de plume of an ancient, learned, and pious writer whose identity remained unknown for some centuries
Idolatry - Etymologically denotes divine worship given to an image, but its signification has been extended to all divine worship given to anyone or anything but the true God
Idumea - The country inhabited by the descendants of Edom
Ignatius Loyola, Saint - Biography of the Spanish founder of the Jesuits, who died in 1556
Ignatius of Antioch, Saint - Biography of the bishop and writer. Ignatius was martyred at Rome sometime between 98 and 117
Ignorance - Lack of knowledge about a thing in a being capable of knowing
IHS - A monogram of the name of Jesus Christ
Illegitimacy - As generally defined, and as understood in this article, illegitimacy denotes the condition of children born out of wedlock
Illinois - One of the United States of America, bounded on the north by Wisconsin, on the west by the Mississippi, which separates it from Iowa and Missouri, on the south by the confluent waters of the Mississippi and the Ohio, which separate it from Kentucky, on the east by Indiana and Lake Michigan
Illuminated Manuscripts - A large number of manuscripts covered with painted ornaments
Illuminati - Secret society founded in 1776
Illuminative Way - Stages in the spiritual life
Illyria - A district of the Balkan Peninsula, which has varied in extent at different periods
Images, Veneration of - It is an uncompromising attitude in the late Jewish history, together with the apparently obvious meaning of the First Commandment, that are responsible for the common idea that Jews had no images
Imagination - The faculty of representing to oneself sensible objects independently of an actual impression of those objects on our senses
Imitation of Christ - A work of spiritual devotion, also sometimes called the 'Following of Christ'. Its purpose is to instruct the soul in Christian perfection with Christ as the Divine Model
Immaculate Conception - In the Constitution Ineffabilis Deus of 8 December, 1854, Pius IX pronounced and defined that the Blessed Virgin Mary 'in the first instance of her conception, by a singular privilege and grace granted by God, in view of the merits of Jesus Christ, the Saviour of the human race, was preserved exempt from all stain of original sin.'
Immanence - Latin, in manere, to remain in. The quality of any action which begins and ends within the agent
Immanuel - Signifies 'God with us' (Matthew 1:23), and is the name of the child predicted in Isaias 7:14: 'Behold a virgin shall conceive, and bear a son, and his name shall be called Emmanuel'
Immortality - By immortality is ordinarily understood the doctrine that the human soul will survive death, continuing in the possession of an endless conscious existence
Immunity - An exemption from a legal obligation (munus), imposed on a person or his property by law, custom, or the order of a superior
Impanation - An heretical doctrine according to which Christ is in the Eucharist through His human body substantially united with the substances of bread and wine, and thus is really present as God, made bread
Impediments, Canonical - Canon law uses the word impediment in its restricted and technical sense, only in reference to marriage, while impediments to Holy orders are spoken of as irregularities
Imperative, Categorical - A term which originated in Immanuel Kant's ethics
Imperfect Contrition - Also called 'imperfect contrition.' Definition, its relation to sacramental penance, and moral considerations
Imposition of Hands - A symbolical ceremony by which one intends to communicate to another some favour, quality or excellence (principally of a spiritual kind), or to depute another to some office
Impostors - That there would be hypocrites who would take advantage of a profession of piety to mask their own evil designs had been clearly foretold by Christ in the Gospels
In Partibus Infidelium - A term meaning 'in the lands of the unbelievers,' words added to the name of the see conferred on non-residential or titular Latin bishops
In Petto - An Italian translation of the Latin in pectore, 'in the breast', i.e. in the secret of the heart
Incardination and Excardination - In the ecclesiastical sense the words are used to denote that a given person is freed from the jurisdiction of one bishop and is transferred to that of another
Incarnation, The - The Incarnation is the mystery and the dogma of the Word made Flesh
Incense - An aromatic substance which is obtained from certain resinous trees and largely employed for purposes of religious worship
Incest - Sexual intercourse between those who are related by blood or marriage
Index of Prohibited Books - The exact list or catalogue of books, the reading of which was once forbidden to Catholics by the highest ecclesiastical authority
India - The peninsula is separated on the north from Tibet and Central Asia by the Himalaya, Hindu Kush, and Karakoram mountains, and some lower ranges divide it from Afghanistan and Baluchistan
Indians, American - History, customs, and language are covered here
Indifferentism, Religious - The term given, in general, to all those theories, which, for one reason or another, deny that it is the duty of man to worship God by believing and practicing the one true religion
Individualism - The tendency to magnify individual liberty, as against external authority, and individual activity, as against associated activity
Individual, Individuality - An individual being is defined by St. Thomas as 'quod est in se indivisum, ab aliis vero divisum' (a being undivided in itself but separated from other beings)
Indo-China - The most easterly of the three great peninsulas of Southern Asia, is bounded on the north by the mountains of Assam, the Plateau of Yun-nan, and the mountains of Kwang-si; on the east by the province of Kwang-si (Canton), the Gulf of Tong-king, and the Sea of China; on the south by the Sea of China, the Gulf of Siam and the Strait of Malacca; on the west by the Gulf of Martaban and the Bay of Bengal
Induction - Induction is the conscious mental process by which we pass from the perception of particular phenomena (things and events) to the knowledge of general truths
Indulgences - A remission of the temporal punishment due to sin, the guilt of which has been forgiven
Indulgences, Apostolic - Those which the Roman pontiff, the successor of the Prince of the Apostles, attaches to the crosses, crucifixes, chaplets, rosaries, images, and medals which he blesses, either with his own hand or by those to whom he has delegated this faculty
Indult, Pontifical - General faculties granted by the Holy See to bishops and others, of doing something not permitted by the common law
Infallibility - In general, exemption or immunity from liability to error or failure; in particular in theological usage, the supernatural prerogative by which the Church of Christ is, by a special Divine assistance, preserved from liability to error in her definitive dogmatic teaching regarding matters of faith and morals
Infamy - Loss of a good name
Infanticide - Child-murder; the killing of an infant before or after birth
Infidels - As in ecclesiastical language those who by baptism have received faith in Jesus Christ and have pledged Him their fidelity and called the faithful, so the name infidel is given to those who have not been baptized
Infinity - The infinite, as the word indicates, is that which has no end, no limit, no boundary, and therefore cannot be measured by a finite standard, however often applied; it is that which cannot be attained by successive addition, not exhausted by successive subtraction of finite quantities
Infralapsarians - The name given to a party of Dutch Calvinists in the seventeenth century, who sought to mitigate the rigour of Calvin's doctrine concerning absolute predestination
Ingres, Jean-Auguste Dominique - A French painter, b. at Montauban, 29 August, 1780; d. at Paris, 14 January, 1867
Injustice - The violation of another's strict right against his reasonable will, and the value of the word right is determined to be the moral power of having or doing or exacting something in support or furtherance of one's own advantage
Innocent I, Pope - Unanimously chosen to succeed Anastasius. Essay on his writings and some of the more notable events of his pontificate. Innocent died in 417
Innocent II, Pope - Reigned 1130-1143
Innocent III, Pope - Reigned 1198-1216
Innocent IV, Pope - Reigned 1243-1254
Innocent V, Blessed Pope - French Dominican, known as 'most famous doctor,' d. 1276
Innocent VI, Pope - Reigned 1352-1362
Innocent VII, Pope - Reigned 1406
Innocent VIII, Pope - Reigned 1484-1492
Innocent IX, Pope - Reigned 1591
Innocent X, Pope - Reigned 1644-1655
Innocent XI, Pope - Lengthy biography of this pope known for his piety and unselfish devotion to duty
Innocent XII, Pope - Reigned 1691-1700
Innocent XIII, Pope - Reigned 1721-24
Inquisition - By this term is usually meant a special ecclesiastical institutional for combating or suppressing heresy
Insane, Asylums and Care for the - The Church, from the earliest times, arranged for the care of the insane
Insanity - The dividing line between sanity and insanity, like the line that distinguishes a man of average height from a tall man, can be described only in terms of a moral estimate
Inscriptions, Early Christian - Divided into three main classes: sepulchral inscriptions, epigraphic records, and inscriptions concerning private life
Inspiration of the Bible - Covered in four sections, I. Belief in Inspired books; II. Nature of Inspiration; III. Extent of Inspiration; IV. Protestant Views on the Inspiration of the Bible
Installation - This word, strictly speaking, applies to the solemn induction of a canon into the stall or seat which he is to occupy in the choir of a cathedral or collegiate church
Instinct - The term usually includes the idea of a purposive adaptation of an action or series of actions in an organized being, not governed by consciousness of the end to be attained
Institute of the Brothers of the Christian Schools - A society of male religious approved by the Church, but not taking Holy orders, and having for its object the personal sanctification of its members and the Christian education of youth, especially of the children of artisans and the poor
Intellect - The faculty of thought
Intention - An act of the will by which that faculty efficaciously desires to reach an end by employing the means
Intercession - To go or come between two parties, to plead before one of them on behalf of the other
Interdict - Originally in Roman law, an interlocutory edict of the praetor, especially in matter affecting the right of possession; it still preserves this meaning in both Roman and canon law
Interest (in Economics) - A value exacted or promised over and above the restitution of a borrowed capital
Introit - The Introit (Introitus) of the Mass is the fragment of a psalm with its antiphon sung while the celebrant and ministers enter the church and approach the altar
Intrusion - The act by which unlawful possession of an ecclesiastical benefice is taken
Intuition - A psychological and philosophical term which designates the process of immediate apprehension or perception of an actual fact, being, or relation between two terms and its results
Investitures, Conflict of - The terminus technicus for the great struggle between the popes and the German kings Henry IV and Henry V, during the period 1075-1122
Invincible Armada, The - A fleet intended to invade England and to put an end to the long series of English aggressions against the colonies and possessions of the Spanish Crown
Ireland - Ireland lies in the Atlantic Ocean, west of Great Britain . . .
Irenaeus, Saint - Article on the bishop of Lyons, Father of the Church, d. late second or early third century
Irish, The (outside Ireland) - Includes the United States, Australia, Canada, Great Britain, South Africa, and South America
Irish Confessors and Martyrs - The period covered by this article embraces that between the years 1540 and (approximately) 1713
Irish Literature - It is uncertain at what period and in what manner the Irish discovered the use of letters. It may have been through direct commerce with Gaul, but it is more probable, as McNeill has shown in his study of Irish oghams, that it was from the Romanized Britons that they first learned the art of writing
Iroquois - A noted confederacy of five, and afterwards six, cognate tribes of Iroquoian stock, and closely cognate languages, formerly occupying central New York, and claiming right of conquest over nearly all the tribes from Hudson Bay to Tennessee River, and westward to Lake Michigan and Illinois River
Irregularity - A canonical impediment directly impeding the reception of tonsure and Holy orders or preventing the exercise of orders already received
Irvingites - A religious sect called after Edward Irving (1792-1834), a deposed Presbyterian minister
Isaac - The son of Abraham and Sara
Isaac Jogues, Saint - French Jesuit missionary to Canada, martyred in 1646
Isabella I - Queen of Castile (1451-1504)
Isabel of France, Saint - Daughter of Blanche of Castille and sister of St. Louis IX. Founded a convent of Poor Clares. Died 1270
Isaias - Essay on the Biblical prophet and the book which bears his name
Ishmael - Son of Abraham and Hagar
Isidore of Seville, Saint - Biographical entry for this bishop, who died in 636
Isidore the Labourer, Saint - Spanish day laborer, married to St. María de la Cabeza. He died in 1130
Islam (Concept) - An Arabic word which, since Mohammed's time, has acquired a religious and technical significance denoting the religion of Mohammed and of the Koran, just as Christianity denotes that of Jesus and of the Gospels, or Judaism that of Moses, the Prophets, and of the Old Testament
Islam (Religion) - Mohammed, 'the Praised One', the prophet of Islam and the founder of Mohammedanism, was born at Mecca (20 August?) A.D. 570
Ismael - Son of Abraham and Hagar
Israelites - The word designates the descendants of the Patriarch Jacob, or Israel
Italian Literature - The modern language of Italy is naturally derived from Latin, a continuation and development of the Latin actually spoken among the inhabitants of the peninsula after the downfall of the Roman Empire
Italians in the United States - Information on distribution, statistics, and religion
Italy - In ancient times Italy had several other names: it was called Saturnia, in honour of Saturn; Enotria, wine-producing land; Ausonia, land of the Ausonians; Hesperia, land to the west (of Greece); Tyrrhenia, etc. The name Italy, which seems to have been taken from vitulus, to signify a land abounding in cattle, was applied at first to a very limited territory
Ite Missa Est - This is the versicle chanted in the Roman Rite by the deacon at the end of Mass, after the Post-Communions
Ives, Saint - Or St. Yves. Patron saint of lawyers, d. 1303
Ivory - The tusks of the elephant, hippopotamus, walrus, and other animals: a tough and elastic substance, of a creamy white, taking a high and lasting polish, largely employed in the arts since pre-historic times, and used extensively in making or adorning ecclesiastical objects by the primitive and medieval Christians
Copyright © 2023 by New Advent LLC. Dedicated to the Immaculate Heart of Mary.