"As an organic chemist, turned geologist, turned astronomer who uses isotopic analyses to unravel the origins of life, our planet, the solar system and the stars, I hope I have something in common with the versatile men who were early Gresham Professors. The subjects which I research already enjoy popular interest; by combining them to produce a story of life told from the genealogy of its elements, my aim is to appeal to the widest possible audience, using an interdisciplinary approach to attempt to unravel the time-honoured puzzle, where do I come from?"