 He married a fellow Quaker, Frances Fettiplace, in 1686, and they had six children between 1687 and 1695, although one died shortly after birth.From 1695 to his death in 1725, he was continually involved in writing innovative tracts on social issues, including education, health provision, care for the poor, support for refugees, a plan for a European State, and an argument for the abolition of capital punishment, making him "the first European advocate of the abolition of capital punishment".He became a Fellow of the Royal Society in February, 1719.