This book makes a forceful, scientific case for an international auxiliary language as a practical tool for modern scholarship, commerce, and everyday communication. Framed by a collaborative preface from leading European thinkers, it argues that the language question has outgrown enthusiasm and become a serious subject for methodical study, one in which science, as a borderless community, should lead the way. The chapters trace the need for a shared scientific medium, showing how reliance on many national languages wastes time, restricts access to research, and complicates conferences and publications. Rejecting both Latin revival and the adoption of any single national tongue, the author proposes a neutral language built from elements common to major European languages and defends it as simple, logical, and easy for educated readers to learn. The book also recounts the work of the Paris Delegation, its remarkable international support, and the long history of universal-language efforts from Descartes and Leibnitz to Volapük. A substantial critique of Esperanto follows, balancing pointed objections to its grammar, spelling, and vocabulary with respect for Zamenhof's achievement and its proven value in international exchange. This edition has been fully restored with modern typesetting, custom cover design.