This book extensively explores the various influences and connections between Joseph Ratzinger and a number of leading philosophers; engaging with his work by means of Spanish, Portuguese, German, and English schools of thought through the contributions of a global body of scholars Each chapter in this volume examines precisely how Ratzinger has dealt with the ideas of a particular philosopher, and how he has appropriated their ideas and thoughts. Moving from philosophers he has modified or critiqued – such as Newman, Comte or Guardini – to those who have contributed to his philosophical theology, this truly international endeavour is an extraordinary journey into Ratzinger’s engagement with his competing schools of thought.