"My introduction to Stephen Jay Gould's work came in the 1970s, when I avidly read all his articles in Natural History (as I still do today). In 1990, when I was asked by a London newspaper to name my favorite book, I selected Wonderful Life; this led to my receiving a letter from Stephen and to the beginning of a frequent and voluminous correspondence between us. Many subjects close to both our hearts have been discussed in letters: from the place of contingency (in evolution but also in the often unpredictable reactions of patients to illnesses and drugs) to our shared love for museums (especially the old "cabinet" type—we both spoke out for the preservation of the Mutter Museum in Philadelphia). In 1993 I wrote of ways of joining particulars with generalities—in my own case, clinical narratives with neuroscience—and he replied: "I have long experienced exactly the same tension, trying to assuage my delight in individual things through my essays and my interest in generality through my more technical writing. I loved the Burgess Shale work so much because it allowed me to integrate the two." I often wrote excited letters to Stephen the moment I had read his columns: in 1995, about his article on Sacculina, a meditation on whether such a life-form could be called degenerate; and in 1996, about some just-published research of his on microevolutionary processes and hybridization effects. I was especially fascinated by his 1998 article on Buffon's trajectory from his early Platonic thinking to a historical viewpoint—partly because of a similar evolution in my own thinking. Stephen is now a good friend as well as a colleague—we dine together, walk the streets together (only someone as intensely sensitive to architecture as he is would introduce spandrels as an evolutionary metaphor), celebrate birthdays together (when Stephen often exercises his talent for composing verses on the spot), go to museums and botanical gardens together. He is an enchanting companion as well as a major intellectual force, and both aspects of him come together in his unique essays."