MOORE, G.E. Principia Ethica. Cambr., 1903. xxvii, (1), 232 pp. Or. gilt lettered cl. (Sm. stain on spine, remnants of ticket on back side). First edition. -- Id. Philosophical Studies. Lond., 1922 (=after 1937, see ads at the end). viii, 342, (2), 20 pp. Or. gilt lettered cl. -- (2).