This book investigates the conception of finality in nature («teleology») in Immanuel Kant’s «critical philosophy» and in Maurice Blondel’s work. The introduction explains the genuine necessity of a reflection on the problem of finality in nature and the role Kant’s and Blondel’s philosophies could play in it. The first part of the study describes Kant’s teleology from the perspective of the whole of his «critical philosophy» and shows both its strengths and its weaknesses. The second part exposes Blondel’s conception of finality in nature and explains how it can be seen as a successful effort to cope with the problems of Kantian thought. In conclusion, the work underlines the inevitability of teleology as an epistemic approach to nature and its value for a contemporary world view.