The study describes and develops the basic motifs of Nancy’s essay L’Intrus. Nancy’s philosophical reflection of the experience of a person who underwent a heart transplant is compared to Merleau-Ponty’s chiasmatic conception of embodiment which acts as a basis for the description of relations between one’s own and another’s, the mutual confusion, intermingling and displacement of which is interpreted in L’Intrus. The polarity of one’s own and not one’s own, played out in connection with the transplantation of a donated organ, is sharpened by the polarity of life and death, which is the ultimate theme here. Despite all the sharpness of this polarity, the border between life and death in the context of modern thinking and modern medical technology is becoming difficult to grasp as is shown, in an exemplary fashion, by Agamben’s reflections on the concept of bare life.