Lady Mary Shepherd  Lady Mary Shepherd, "née" Primrose (31 December 1777 – 7 January 1847) was a Scottish philosopher who published two philosophical books, one in 1824 and one in 1827. According to Robert Blakey, who gave her an entry in his "History of the Philosophy of the Mind", she exercised considerable influence over the Edinburgh philosophy of her day. Lady Mary Primrose was the second daughter of Neil Primrose, 3rd Earl of Rosebery. She was born at Barnbougle Castle on the family estate near Dalmeny, Midlothian. Privately educated, she married an English barrister, Henry John Shepherd, in 1808. Although Shepherd's philosophical books only appeared in the 1820s, a memoir by her daughter indicates that their composition in fact predated her marriage. In the first, an essay on the relation between cause and effect, she criticised the views of David Hume, Thomas Brown and the physiologist William Lawrence. In her second book of essays, on the perception of an external universe, she argued against both the idealism of George Berkeley and Thomas Reid's epistemological reliance on natural instinct. Shepherd's correspondence shows a continuing interest in philosophical questions. A private philosophical controversy with the amateur philosopher John Fearn over the relation between perception and physical extension was published in "Parriana" (1828). After learning of its publication, Shepherd wrote in defence of her position in "Fraser's".