Why a manual? Because it aspires to be easy to use and easy to understand, and its intention is fundamentally practical. Because it is not an official, academic, or doctrinaire book, and it summarizes the most substantial aspects of several philosophical lives. Why portable? Because it is a tribute to wanderers. Portable philosophy is an effort to liberate thought from the seclusion to which it has been subjected by scholastics and academics. A way to ward off that erudite mania of speaking only to those who share a chair or faculty. The spirit of ponderousness infects philosophy like no other, and the portable book is a ballast reliever. It prefers to offer ironies, crumbs, and glimpses that pave the way for a new understanding of life. This book proposes traveling upstream along the river of philosophy, in search of its sources. The journey begins with the gesture of an anthropologist who, after studying philosophy in Paris, goes to seek the truth among the "savages." Then we visited the philosophers, witnessing unforgettable scenes: Wittgenstein taking notes in a trench, Nietzsche whispering to a horse, Kierkegaard funding an anti-clerical pamphlet, Leibniz discovering love between princesses, Montaigne barricading himself in a fortress, Plotinus concealing his past, Socrates willingly drinking poison, and Empedocles throwing himself into a volcano. What at first glance might seem strange held profound meaning for all of them. Let's call that meaning philosophy and see what happened.