Dio Chrysostom, Dion of Prusa or Cocceianus Dio, was a Greek orator, writer, philosopher and historian of the Roman Empire in the 1st century AD. Eighty of his Discourses are extant, as well as a few letters, a mock essay Encomium on Hair, and a few other fragments. His sobriquet Chrysostom comes from the Greek chrysostomos, which literally means "golden-mouthed".
Diodore of Tarsus was a Christian bishop, a monastic reformer, and a theologian. A strong supporter of the orthodoxy of Nicaea, Diodore played a pivotal role in the Council of Constantinople and opposed the anti-Christian policies of Julian the Apostate. Diodore founded one of the most influential centers of Christian thought in the early church, and many of his students became notable theologians in their own right.
Diodorus Siculus, or Diodorus of Sicily was an ancient Greek historian. He is known for writing the monumental universal history Bibliotheca historica, in forty books, fifteen of which survive intact, between 60 and 30 BC.
The history is arranged in three parts. The first covers mythic history up to the destruction of Troy, arranged geographically, describing regions around the world from Egypt, India and Arabia to Europe. The second covers the time from the Trojan War to the death of Alexander the Great. The third covers the period to about 60 BC. Bibliotheca, meaning 'library', acknowledges that he was drawing on the work of many other authors.
Diogenes, also known as Diogenes the Cynic or Diogenes of Sinope, was a Greek philosopher and one of the founders of Cynicism. He was born in Sinope, an Ionian colony on the Black Sea coast of Anatolia in 412 or 404 BC and died at Corinth in 323 BC.
Diogenes Laërtius was a biographer of the Greek philosophers. Nothing is definitively known about his life, but his surviving Lives and Opinions of Eminent Philosophers is a principal source for the history of ancient Greek philosophy. His reputation is controversial among scholars because he often repeats information from his sources without critically evaluating it. He also frequently focuses on trivial or insignificant details of his subjects' lives while ignoring important details of their philosophical teachings and he sometimes fails to distinguish between earlier and later teachings of specific philosophical schools. However, unlike many other ancient secondary sources, Diogenes Laërtius generally reports philosophical teachings without attempting to reinterpret or expand on them, which means his accounts are often closer to the primary sources. Due to the loss of so many of the primary sources on which Diogenes relied, his work has become the foremost surviving source on the history of Greek philosophy.
Diogenes of Apollonia was an ancient Greek philosopher, and was a native of the Milesian colony Apollonia in Thrace. He lived for some time in Athens. He believed air to be the one source of all being from which all other substances were derived, and, as a primal force, to be both divine and intelligent. He also wrote a description of the organization of blood vessels in the human body. His ideas were parodied by the dramatist Aristophanes, and may have influenced the Orphic philosophical commentary preserved in the Derveni papyrus. His philosophical work has not survived in a complete form, and his doctrines are known chiefly from lengthy quotations of his work by Simplicius, as well as a few summaries in the works of Aristotle, Theophrastus, and Aetius.
Diogenes of Babylon was a Stoic philosopher. He was the head of the Stoic school in Athens, and he was one of three philosophers sent to Rome in 155 BC. He wrote many works, but none of his writings survived, except as quotations by later writers.
Diogenes of Oenoanda was an Epicurean Greek from the 2nd century AD who carved a summary of the philosophy of Epicurus onto a portico wall in the ancient Greek city of Oenoanda in Lycia. The surviving fragments of the wall, originally extended about 80 meters, form an important source of Epicurean philosophy. The inscription, written in Greek, sets out Epicurus' teachings on physics, epistemology, and ethics. It was originally about 25,000 words long and filled 260 square meters of wall space. Less than a third of it has been recovered.
