This book offers the reader a part of the life of a philosopher, his "reasoned life." And he does it through a series of collaborations of friends and colleagues who know him well and in which they show him both his personal and intellectual appreciation. The work divides that life into four parts. The first - Biographical and Philosophical - intertwines his biography with the abundant production of the honoree. The other three -Fenomenológica, Orteguiana, Antropológica- present current discussions in many other fields of philosophy and human sciences whose flowering in the Spanish language has contributed so much to Javier San Martín.