[Mark Twain (subject)]. Paul Carus. The Mechanistic Principle and the Non-Mechanical. An Inquiry Into Fundamentals with Extracts from Representatives of Either Side. Chicago: The Open Court Publishing Company, 1913. First edition. Octavo (9 x 6 inches; 225 x 150 mm.). iv, 125, [3, blank] pages. In-text illustration on page 99. Publisher's smooth green cloth, spine and front board lettered in dark green, front board ruled in same; all edges of the text block trimmed; plain endpapers. Spine ends and corners very lightly worn; a few touches of very slight wear to the boards. Faint discoloration to the endpapers, likely from an old tissue jacket (no longer present). Near fine. Pages 54-97 devoted to Mark Twain's Philosophy with excerpts from "What Is Man?" (#10225).