THIS PROJECT started nearly half a century ago when I was writing my first book, The Philosophy of Biology (1973). Framed very much in the school of “logical empiricism”—the leaders were two men whose names and memory I still revere, Ernest Nagel and Carl “Peter” Hempel—everything was going along swimmingly until I got to the chapter on function or purpose. Something went wrong, for I could not fit the discussion into the mold, especially the mold of science as a value-free inquiry, as an enterprise that drains itself of the human element—in Karl Popper’s felicitous phrase, “knowledge without a knower.” Eventually, I plowed on, or rather through, and the book was finished and published. But the problem of purpose kept nagging away—even back then I think I had insights into the way things had to go—and it has been a lifetime’s quest for understanding, frustrating at times but incredibly invigorating. Now I think I know the answer, and it is here in this book, the summing up of a fifty-year obsession with the problem.
So, first, I want to thank Nagel and Hempel for setting me off on this quest. It was from them, as well as from others in the field, I learned that philosophy never stands still; there is always work to be done, criticizing and extending. An insight that never withers is that you learn most from those with whom you disagree most, and I very much hope that this book exemplifies this truth. I am very grateful to my fellow philosophers who have so stimulated me. In a rather different way, I want to thank Plato and Aristotle, Kant and Darwin. As you will see, my quest has taken me back to their writings. It has been a great privilege to spend time with minds such as these. If my huge respect for and sheer enjoyment and excitement at what they produced does not come across on every page, then I have failed myself, I have failed you the reader, and, most sadly, I have failed them. I want this book read in a positive manner. I shall have critical things to say but always in the sense of wanting to move the conversation forward.
At the immediate level, my thanks above all go to my editor at Princeton University Press, Rob Tempio. When he first asked me to write this book, I agreed, believing that it would be a good way of summing up ideas about which I have been thinking and writing for many years. Deftly, he steered me toward imposing on my material a new and, I think, informative framework, looking at old problems in a way that hitherto I had grasped but vaguely. At times, responding to Rob’s comments, as well as to those of the referees he so astutely chose, I wondered why he and they didn’t simply write the book themselves. Socrates once said he was the wisest man alive since he knew one thing, namely, that he knew nothing. Yes, indeed.
I am most grateful to my colleagues, Nat Stein and Randy Clarke, for looking at an earlier version of my manuscript and giving me useful comments. My dear friend, professor at Fordham University and the English-speaking world’s foremost authority on Thomas Aquinas, Brian Davies, pointed to the egregious mistakes I made about the great Christian philosophers. Given the melancholic pleasure that this gave him, I am sure that there is lurking there a new ontological argument about my necessary existence. I am deeply in the debt of my student, assistant, and, above all, friend Jeff O’Connor for doing more of the humdrum jobs than one has any right to ask of any person. As always, I pay grateful memory to William and Lucyle Werkmeister, whose legacy made possible my professorship and the research funds attached to it. And finally, above all, I celebrate the love and warm companionship of my family, especially my daughter, Emily, whom you will be meeting, and my wife, Lizzie. You will later learn the context when I say that the trade-off for spending so much time being antisocial and writing this book is that Nutmeg arrived into our lives.