Thinker's Library

The Thinker's Library was a series of 140 small hardcover books published between 1929 and 1951 for the Rationalist Press Association by Watts & Co., London, a company founded by Charles Albert Watts. They consisted of a selection of essays, literature, and extracts from greater works by various classical and contemporary humanists and rationalists, continuing in the tradition of the Renaissance. Many of the titles were cheap reprints of classic books, aimed at a mass audience.

Each volume consists of an eponymous essay sometimes followed by a collection of related essays by the same author, or an introductory extract from a greater work by that author. Any deviation from this format will be self-explanatory from the title. All foreign language texts were published in the English language.

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