Shirley Williams's political career (the House of Commons regularly sat until 10 pm) meant that the couple spent a lot of time apart. They bought a house in Furneux Pelham, Hertfordshire, near the border with south Cambridgeshire, while she lived in Phillimore Place during the week to be close to the Houses of Parliament. Sunday was often the only day they were together. The differences in their personal values – he was an atheist, she a Catholic – placed a further strain on their relationship. It reached breaking point in 1970 when Williams formed a relationship with Patricia Law Skinner, a commissioning editor for Cambridge University Press and wife of the historian Quentin Skinner. She had approached Williams to write the opposing view of utilitarianism for "Utilitarianism: For and Against" with J. J. C. Smart (1973), and they had fallen in love.