" Until Harriet Hemings left in 1822, Jefferson had never freed a female slave. There may have been several reasons for this, but we know at least one that was probably the most important to him. Two years before Harriet Hemings left Monticello, Jefferson wrote a letter to his former son-in-law John Eppes in which he said that he considered female slaves to be far more valuable than male slaves. Why? Because female slaves had children and, thus, added to capital.43 At the time of Harriet’s departure, Jefferson was in dire financial circumstances. Bad economic times in Virginia, along with Jefferson’s expensive way of life, had set him on "

― Annette Gordon-Reed , Thomas Jefferson and Sally Hemings: An American Controversy