David Hartley the Younger (1732 – 19 December 1813) was an English politician and inventor and the son of the philosopher David Hartley. He was Member of Parliament (MP) for Kingston upon Hull, and also held the position of His Britannic Majesty's Minister Plenipotentiary, appointed by King George III to treat with the United States of America as to American independence and other issues after the American Revolution. He was a signatory to the 1783 Treaty of Paris, which ended the American Revolutionary War. Hartley was the first MP to put the case for abolition of the slave trade before the House of Commons, moving a resolution in 1776 that "the slave trade is contrary to the laws of God and the rights of men".[1]