Jaedenholm, Gustav Aksel Letters to Pearson regarding the publication of his new book [possibly <i>Undersökningar över intelligensmätningarnas teori och praxis</i>]; thanking Pearson for his assistance; regarding Jaedenholm's career possibilities; helping Pearson send postcards to Germany; discussing the First World War; the work of [James McKeen?] Cattell; Jaedenholm's research into the history and psychology of ethics; and the possibility of making a research trip to England during the war. 1914-1917