The one-volume Propædia is the first of three parts of the 15th edition of Encyclopædia Britannica, intended as a compendium and topical organization of the 12-volume Micropædia and the 17-volume Macropædia, which are organized alphabetically. Introduced in 1974 with the 15th edition, the Propædia and Micropædia were intended to replace the Index of the 14th edition; however, after widespread criticism, the Britannica restored the Index as a two-volume set in 1985. The core of the Propædia is its Outline of Knowledge, which seeks to provide a logical framework for all human knowledge. However, the Propædia also has several appendices listing the staff members, advisors and contributors to all three parts of the Britannica. The last edition of the print Britannica was published in 2010.

Outline of Knowledge

Like the Britannica as a whole, the Outline has three types of goals: According to Mortimer J. Adler, the designer of the Propaedia, all articles in the full Britannica were designed to fit into the Outline of Knowledge. The Outline has 167 sections, which are categorized into 41 divisions and then into 10 parts. Each part has an introductory essay written by the same individual responsible for developing the outline for that part, which was done in consultation and collaboration with a handful of other scholars. In all, 86 men and one woman were involved in developing the Outline of Knowledge. The Outline was an eight-year project of Mortimer J. Adler, published 22 years after he published a similar effort (the Syntopicon) that attempts to provide an overview of the relationships among the "Great Ideas" in Adler's Great Books of the Western World series. (The Great Books were also published by the Encyclopædia Britannica Inc.) Adler stresses in his book, A Guidebook to Learning: For a Lifelong Pursuit of Wisdom, that the ten categories should not be taken as hierarchical but as circular. "The whole of the Propædia's synoptic outline of knowledge deserves to be read carefully. It represents a twentieth-century scheme for the organization of knowledge that is more comprehensive than any other and that also accommodates the intellectual heterodoxy of our time."

• Mortimer J. Adler, in A Guidebook, pp. 91–2

Contents

1. Matter and Energy

The lead author was Nigel Calder, who wrote the introduction "The Universe of the Physicist, the Chemist, and the Astronomer".

2. The Earth

The lead author was Peter John Wyllie, who wrote the introduction "The Great Globe Itself".

3. Life

The lead author was René Dubos, who wrote the introduction "The Mysteries of Life".

4. Human Life

The lead author was Loren Eiseley, who wrote the introduction "The Cosmic Orphan".

5. Society

The lead author was Harold D. Lasswell, who wrote the introduction "Man the Social Animal".

6. Art

The lead author was Mark Van Doren, who wrote the introduction "The World of Art".

7. Technology

The lead author was Lord Peter Ritchie-Calder, who wrote the introduction "Knowing How and Knowing Why".

8. Religion

The lead author was Wilfred Cantwell Smith, who wrote the introduction "Religion as Symbolism".

9. History

The lead author was Jacques Barzun, who wrote the introduction "The Point and Pleasure of Reading History".

10. Branches of Knowledge

The lead author was Mortimer J. Adler, who wrote the introduction "Knowledge Become Self-conscious".

Contributors to the Outline of Knowledge

Section 4.2.1 uses transparencies of organ systems originally commissioned by Parke-Davis. Similar in design to the three-dimensional Visible Man and Visible Woman dolls designed by sculptor Marcel Jovine, successive plastic sheets reveal different layers of human anatomy.