This is the first volume of the first ever comprehensive edition of the works of Immanuel Kant in English translation. The eleven essays in this volume constitute Kant's theoretical, pre-critical philosophical writings from 1755 to 1770. Several of these pieces have never been translated into English before; others have long been unavailable in English. We can trace in these works the development of Kant's thought to the eventual emergence in 1770 of the two chief tenets of his mature philosophy: the subjectivity of space and time, and the phenomena-noumena distinction. The volume has been furnished with substantial editorial apparatus, including a general introduction to the main themes of Kant's early thought, introduction to the individual works and resumes of their contents, linguistic and factual notes, bibliographies, a glossary of key terms, and biographical-bibliographical sketches of persons mentioned by Kant.