This is the first monograph about the young Leibniz’s basic philosophical position since Willy Kabitz’s work seventy years ago. Based partially on texts which became accessible for the first time as a result of the Academy edition, the author studies the significant moments and traditions which shaped the approach of Leibniz’s philosophy as it was being developed. The Leibniz system grew out of persistent work on a few main ideas which surfaced at an early date. The research on Leibniz will gain momentum when the aporias upon which he stumbled are seen as the impulses for his own reflection. With its interpretation of material relevant from the perspective of the history of ideas, this work provides a seminal contribution which in addition sheds new light on the philosophical influences from France in the 17th century.