Royal Australasian Ornithologists Union early 20th century called themselves 'oologists', though the distinction between the notionally scientific discipline of oology and simple egg-collecting was blurred. Identification of any but the most common and distinctive species usually entailed the collection of specimens to be made into study skins. Modern field-guides did not exist and few people could afford the massive multi-volume, lavishly illustrated, handbooks of John Gould and Gregory Mathews. However, both Archibald J. Campbell and Alfred North had produced comprehensive guides to what was known about the nests and eggs of Australian birds, with illustrations of the eggs rather than of the birds themselves,
What Is the Third Estate? and operated by independent associations, and therefore society would be self-governed. A comprehensive collection of writings on the topic was released under "Pluralist Theory of the State". Modern equivalent theories building upon the ideas within pluralistic state theory are libertarian socialism and free-market anarchism. An example of the former is guild socialism, one of the founders of which is G. D. H. Cole mentioned above. What Is the Third Estate? What Is the Third Estate? () is a political pamphlet written in January 1789, shortly before the outbreak of the French Revolution, by the French thinker and clergyman Abbé Emmanuel