It is twenty-six years since I first met Hans Jonas in the pages of his book, The Phenomenon of Life: Toward a Philosophical Biology. I was then a practicing biochemist working at the National Institutes of Health. But I was a some-what eccentric biochemist, both because I had acquired a moralist's interest in the meaning of the new biology and, even more, because I had a vague interest in the philosophy of organism, secretly harboring inarticulate yet definite nonreductionist prejudices. My closest friend, having read Is God a Mathematician? (The Meaning of Metabolism), strongly recommended that I read The Phenomenon of Life, whose paperback edition had just appeared. I took the book with me on our family vacation in West Virginia, and pored over it steadily for two weeks. It left me out of breath from the intellectual effort needed to comprehend the dense and sophisticated philosophical arguments (and the author's Germanic style). At the same time, I was exhilarated to discover that there was indeed a way to philosophize nonreductively about living nature, including man, even in the face of the great accomplishments of modern biology. A few months later, in the autumn of 1969, I met Hans Jonas in the flesh. I had organized the first NIH Symposium on Ethical Issues in Biomedical Advance and, mainly because I wanted to meet him, invited Hans to be the moderator. Look for a short man with a briefcase, holding a cigarette in the European manner, said my prescient wife as I left for the airport to meet my esteemed guest. Following her advice, I picked him out immediately and we soon fell into lively conversation. The next few days were exhilarating. Hans not only moderated with skill and grace; with his opening and closing remarks and his other substantive interventions, he gave the whole proceedings the wished-for and fitting tone of moral and philosophical seriousness. In the years that followed, Hans and I became colleagues at The Hastings Center, mainly as members of the Task Force on Death and Dying. I recall that he served as a commentator on my first paper, on the immorality of human cloning, and his generous and enthusiastic endorsement of my arguments encouraged me greatly. Within the year, inspired largely by his example and that of Paul Ramsey, I took a leave of absence from the laboratory and began a career, first in biomedical ethics, more recently in the humanities more generally, seeking to build bridges between science and ethics, between nature and human affairs. As part of my inquiry, I have, on four or five occasions over the past eighteen years, taught a course on the organism, in each case reading The Phenomenon of Life as the culminating work. My students, like me before them, have found it immensely difficult but immensely rewarding. Two have gone on to write outstanding doctoral dissertations in the history of science, inspired by what they first came to see in this course, thanks to The Phenomenon of Life. Several who are now practicing biologists are keenly aware of the limitations of the objectified view of life and hope in their own work to exhibit alternative ways of thinking and speaking. My own work continues to be nurtured by what I have learned from this and other of Hans's writings and from the friendship we developed over the years. Though I was never formally his student, Hans was and remains my teacher, even about the worthwhileness of teaching. He strongly encouraged me to accept my teaching position at The University of Chicago; and when I would occasionally become discouraged about the worthwhileness of teaching and writing, he would boost my spirits, once quoting Ecclesiastes: Cast thy bread upon the waters; for thou shalt find it in the end of days. By happy accident--or was it providence?--I once got the opportunity to return a small portion of the bread Hans had cast in my direction. One day, when my class was discussing The Phenomenon of Life, a student brought a visitor to class, whom she introduced as the daughter of the author. …