Encyclopedias have progressed from the beginning of history in written form, through medieval and modern times in print, and most recently, displayed on computer and distributed via computer networks.

Western encyclopedias

Ancient times Encyclopedias have existed for around 2,000 years, although even older glossaries such as the Babylonian Urra=hubullu and the ancient Chinese Erya are also sometimes described as "encyclopedias".

Marcus Terentius Varro Marcus Terentius Varro (116 BC – 27 BC) was an ancient Roman scholar and writer.

His Nine Books of Disciplines became a model for later encyclopedists, especially Pliny the Elder. The most noteworthy portion of the Nine Books of Disciplines is its use of the liberal arts as organizing principles. Varro decided to focus on identifying nine of these arts: grammar, rhetoric, logic, arithmetic, geometry, astronomy, musical theory, medicine, and architecture. Using Varro's list, subsequent writers defined the seven classical "liberal arts of the medieval schools".

Pliny the Elder

The earliest encyclopedic work to have survived to modern times is the Naturalis Historia of Pliny the Elder, a Roman statesman living in the 1st century AD. He compiled a work of 37 chapters covering natural history, architecture, medicine, geography, geology, and all aspects of the world around him. He stated in the preface that he had compiled 20,000 facts from 2000 works by over 200 authors, and added many others from his own experience. The work was published around AD 77–79, although he probably never finished proofing the work before his death in the eruption of Vesuvius in AD 79.Naturalis Historia

My subject is a barren one – the world of nature, or in other words life; and that subject in its least elevated department, and employing either rustic terms or foreign, many barbarian words that actually have to be introduced with an apology. Moreover, the path is not a beaten highway of authorship, nor one in which the mind is eager to range: there is not one of us who has made the same venture, nor yet one Greek who has tackled single-handed all departments of the subject.

He also elaborates on the difficulties of writing such a work:

It is a difficult task to give novelty to what is old, authority to what is new, brilliance to the common-place, light to the obscure, attraction to the stale, credibility to the doubtful, but nature to all things and all her properties to nature.

This work became very popular in classical antiquity, and survived, with many copies being made and distributed in the western world. It was one of the first classical manuscripts to be printed in 1470, and has remained popular ever since as a source of information on the Roman world, and especially Roman art, Roman technology and Roman engineering. It is also a recognized source for medicine, art, mineralogy, zoology, botany, geology and many other topics not discussed by other classical authors. Among many interesting entries are those for the elephant and the murex snail, the much sought-after source of Tyrian purple dye.

Although his work has been criticized for the lack of candor in checking the "facts", some of his text has been confirmed by research in the 20th and early 21st centuries, like the spectacular remains of Roman gold mines in Spain, especially at Las Médulas, which Pliny probably saw in operation while a procurator there, a few years before he compiled the encyclopedia. Although many of the mining methods are now redundant, such as hushing and fire-setting, it is Pliny who recorded them for posterity, thereby helping us understand their importance in a modern context. Pliny makes clear the fact in the preface to his work that he had checked his facts by reading and comparing the works of others, as well as referring to them by name. Many such books are now lost works and remembered only by his references, much like the lost sources mentioned in the work of Vitruvius a century earlier.

Middle Ages

The work De nuptiis Mercurii et Philologiae ("About the wedding of Mercury and Philologia") written by Martianus Capella (probably 5th century) was very influential on the successive medieval encyclopedias. It consists in a complete encyclopedia of classical erudition. It firstly introduced the division and classification of the seven liberal arts (trivium and quadrivium), followed by many successive works along the Middle Ages.

The first Christian encyclopedia was the Institutiones divinarum et saecularium litterarum of Cassiodorus (543–560), which were divided in two parts: the first one dealt with Christian Divinity; the second one described the seven liberal arts.

Saint Isidore of Seville, one of the greatest scholars of the early Middle Ages, is widely recognized as being the author of the first known encyclopedia of the Middle Ages, the Etymologiae or Origines (around 630), in which he compiled a sizable portion of the learning available at his time, both ancient and modern. The encyclopedia has 448 chapters in 20 volumes, and is valuable because of the quotes and fragments of texts by other authors that would have been lost had they not been collected by Saint Isidore.

The most popular encyclopedia of the Carolingian Age was the De universo or De rerum naturis by Rabanus Maurus, written about 830, which was based on the Etymologiae.

Many encyclopedic works were written during the 12th and 13th centuries. Among them was Hortus deliciarum (1167–1185) by Herrad of Landsberg, which is thought to be the first encyclopedia written by a woman. De proprietatibus rerum by Bartholomeus Anglicus (1240) is often described as the most widely read and quoted encyclopedia in the High Middle Ages,See "Encyclopedia" in Dictionary of the Middle Ages. while Vincent of Beauvais's Speculum Majus (1260) was the most ambitious encyclopedia in the late-medieval period, at over 3 million words.

The first encyclopedias in vernacular languages were translations or abridgements of works in Latin. Among them, the most famous is Li livre dou Trésor, written in French by the Florentine Brunetto Latini. It is mainly based on the Speculum Majus. The works by the Flemish Jacob van Maerlant, as a whole, are regarded as an encyclopedia. These works, too, are based on former Latin texts. In late medieval Europe, several authors had the ambition of compiling the sum of human knowledge in a certain field or overall, for example Bartholomew of England, Vincent of Beauvais, Radulfus Ardens, Sydrac, Brunetto Latini, Giovanni da Sangiminiano, Pierre Bersuire. Some were women, like Hildegard of Bingen and Herrad of Landsberg. The most successful of those publications were the Speculum Maius (Great Mirror) of Vincent of Beauvais and the De proprietatibus rerum (On the Properties of Things) by Bartholomew of England. The latter was translated (or adapted) into French, Provençal, Italian, English, Flemish, Anglo-Norman, Spanish, and German during the Middle Ages. Both were written in the middle of the 13th century. No medieval encyclopedia bore the title Encyclopaedia – they were often called On nature (De natura, De naturis rerum), Mirror (Speculum maius, Speculum universale), Treasure (Trésor).Monique Paulmier-Foucart, "Medieval Encyclopaedias", in André Vauchez (ed.), Encyclopedia of the Middle Ages, James Clarke & Co, 2002. The first encyclopedic work to adopt a single alphabetical order for entries across a variety of topics was the fourteenth-century Omne Bonum, compiled by James le Palmer.

In the medieval period, Jewish scholars also contributed to the development of encyclopedias. The first known encyclopedia of science by a Jewish author is Yesodei ha-Tevuna u-Migdal ha-Emuna ("The Principles of Understanding and the Tower of Faith"), written by Abraham bar Hiyya, a Catalan Jew, in the early 12th century. In the 13th century, the Spanish Jewish philosopher Judah ben Solomon ha-Kohen composed Midrash Ḥokhmah, originally in Arabic and later translated into Hebrew. The work is partially preserved and is structured in two parts: one dealing with logic, physics, metaphysics, and biblical texts; the other focused on mathematics and the Hebrew alphabet. These works followed an Aristotelian model of organizing knowledge into natural, mathematical, and divine sciences. In the 12th century, Ibn Jumay', a Jewish physician who served as the private doctor to Saladin in Egypt, authored a medical encyclopedia titled Kitāb al-Irshād li-Masāliḥ al-Anfus wa-al-Ajsād ("Guidance for the Welfare of Souls and Bodies"). The work presented therapeutic material and addressed both physical and mental well-being.

Renaissance

These works were all hand copied and thus rarely available, beyond wealthy patrons or monastic men of learning: they were expensive, and usually written for those extending knowledge rather than those using it.

During the Renaissance, the creation of printing allowed a wider diffusion of encyclopedias and every scholar could have his or her own copy.

In 1493, the Nuremberg Chronicle was produced, containing hundreds of illustrations, of historical figures, events and geographical places. Written as an encyclopedic chronicle, it remains one of the best-documented early printed books—an incunabulum—and one of the first to successfully integrate illustrations and text. Illustrations depicted many never before illustrated major cities in Europe and the Near East. 645 original woodcuts were used for the illustrations.

The De expetendis et fugiendis rebus by Giorgio Valla was posthumously printed in 1501 by Aldo Manuzio in Venice. This work followed the traditional scheme of liberal arts. However, Valla added the translation of ancient Greek works on mathematics (firstly by Archimedes), newly discovered and translated.

The Margarita Philosophica by Gregor Reisch, printed in 1503, was a complete encyclopedia explaining the seven liberal arts.

Much encyclopaedism of the French Renaissance was based upon the notion of not including every fact known to humans, but only that knowledge that was necessary, where necessity was judged by a wide variety of criteria, leading to works of greatly varying sizes. Béroalde de Verville laid the foundation for his encyclopaedic works in a hexameral poem entitled Les cognoissances nécessaires for example. Often, the criteria had moral bases, such as in the case of Pierre de La Primaudaye's and Guillaume Telin's Bref sommaire des sept vertus &c.. Encyclopaedists encountered several problems with this approach, including how to decide what to omit as unnecessary, how to structure knowledge that resisted structure (often simply as a consequence of the sheer amount of material that deserved inclusion), and how to cope with the influx of newly discovered knowledge and the effects that it had on prior structures.

The term encyclopaedia was coined by 16th-century humanists who misread copies of their texts of PlinyPliny the Elder, Naturalis Historia, Preface 14. and Quintilian,Quintilian, Institutio oratoria, 1.10.1: ut efficiatur orbis ille doctrinae, quem Graeci ἐγκύκλιον παιδείαν vocant. and combined the two Greek words "enkyklios paedia" into one word, έγκυκλοπαιδεία.έγκυκλοπαιδεία, Henry George Liddell, Robert Scott, A Greek–English Lexicon, at Perseus Project: "f. l. [= falsa lectio, Latin for "false reading"] for ἐγκύκλιος παιδεία" The phrase enkyklios paedia (ἐγκύκλιος παιδεία) was used by Plutarch and the Latin word encyclopaedia came from him. The first work titled in this way was the Encyclopedia orbisque doctrinarum, hoc est omnium artium, scientiarum, ipsius philosophiae index ac divisio written by Johannes Aventinus in 1517.