The Institutes of Oratory (Latin: Institutio Oratoria) is a treatise by Quintilian on the education of an orator. The earliest books consider a child's earliest schooling and entry into rhetorical training. Books 3-7 to consider the technical details of the subject while books 8 to 11 deal with style and delivery. Book 10 is notable for a discussion of the whole of Greek and Latin literature, considered from the rhetorician's point of view. Book 12 concludes the work with a picture of the ideal orator as Cato's 'vir bonus dicendi peritus', a good man who knows how to speak.
Quintilian, a Spanish-born teacher of rhetoric who benefited from the patronage of several emperors, published the Institutes about 95 CE. Pliny the Younger was among his pupils.
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Free online texts
Biblioteca Augustana: Institutionis oratoriae libri duodecim. Latin text, HTML format.
Eserver/Internet Archive: Institutes of Oratory, translated by John Selby Watson. HTML format with additional secondary resources edited by Lee Honeycutt.
Gutenberg: M. Fabi Quintiliani institutionis oratoriae liber decimus. Latin text, multiple formats.
Internet Archive: Quintilian's Institutes of oratory; or, Education of an orator, translated by John Selby Watson (1875). Multiple formats.
Lacus Curtius: Institutio Oratoria, translated by H. E. Butler (1920-22). HTML format.
Latin Library: Institutiones. Latin text, HTML format.
Loebulus. L124N - Quintilian I: Institutio Oratoria Books 1-3. PDF of public domain Loeb edition in Latin and English.
Loebulus. L125N - Quintilian II: Institutio Oratoria Books 4-6. PDF of public domain Loeb edition in Latin and English.
Loebulus. L126N - Quintilian III: Institutio Oratoria Books 7-9. PDF of public domain Loeb edition in Latin and English.
Loebulus.. L127N - Quintilian IV: Institutio Oratoria Books 10-12. PDF of public domain Loeb edition in Latin and English.
Perseus: Institutio Oratoria, translated by H.E. Butler. HTML and XML formats.
Librivox: Institutio Oratoria (On the Education of an Orator) - public domain audiobook.
Michigan State University: The History and Rhetoric of Institutio Oratoria. Archived at the Internet Archive.
Silva Rhetoricae: Outline of Institutio Oratoria.
Wikipedia: Institutio Oratoria.
The Great Conversation: Further reading at Tom's Learning Notes
Cicero: On the Orator.
Tacitus: Dialogue on Orators.
Pliny the Younger: Letters.
Latin resources: Learn to read Latin texts in the original.