On Start the Week Mary-Ann Sieghart asks why some people succeed while others fail. She talks to the journalist Helen Pearson about the Life Project, a study of the health, wellbeing and life chances of thousands of British children, started in 1946. The television producer Joseph Bullman also charts a series of families back to the Victorian times to look at social mobility through the generations. The psychologist Oliver James wades into the nature/ nurture debate by arguing that we are the result of our environment and upbringing, but the scientist Marcus Munafò says there is increasing evidence of genetic links to who we are and what we do. Producer: Katy Hickman.