Nature’s imagination, as Freeman Dyson likes to say, is richer than ours, and he speaks, marvellingly, of this richness in the physical and biological worlds, the endless diversity of physical forms and forms of life. 

For me, as a physician, nature’s richness is to be studied in the phenomena of health and disease, in the endless forms of adaptation by which human organisms, people, adapt and reconstruct themselves, faced with the challenges and vicissitudes of life. Defects, disorders, diseases, in this sense, can play a paradoxical role, by bringing out latent powers, developments, evolutions, forms of life, that might never be seen, or even be imaginable, in their absence.