Question: When did the British philosopher whose works inspired Kate Horsley's interest in Zen die?

Context:
Timothy Williamson
Timothy Williamson, {'1': ", '2': ", '3': ", '4': "} (born 6 August 1955) is a British philosopher whose main research interests are in philosophical logic, philosophy of language, epistemology and metaphysics.
John Skorupski
John Skorupski (born 19 September 1946) is a British philosopher whose main interests are epistemology, ethics and moral philosophy, political philosophy, and the history of 19th and 20th century philosophy.
 He is best known for his work on John Stuart Mill and his study of normativity, "The Domain of Reasons".
Qu You
Qu You (, 1341–1427), courtesy name Zongji (宗吉) and self-nicknamed Cunzhai (存齋, "Reading Studio of Existence"), was a Chinese novelist who lived in the Ming Dynasty, and whose works inspired a new genre fantasy works with political subtext of the Qing Dynasty.
Cid Ricketts Sumner
Cid Ricketts Sumner (September 27, 1890 – October 15, 1970) was a novelist from the United States whose works inspired several Hollywood films.
 She also taught English at a Jackson, Mississippi, high school and French at Millsaps College.
Alan Watts
Alan Wilson Watts (6 January 1915 – 16 November 1973) was a British philosopher, writer, and speaker, best known as an interpreter and populariser of Eastern philosophy for a Western audience.
 Born in Chislehurst, England, he moved to the United States in 1938 and began Zen training in New York.
 Pursuing a career, he attended Seabury-Western Theological Seminary, where he received a master's degree in theology.
 Watts became an Episcopal priest in 1945, then left the ministry in 1950 and moved to California, where he joined the faculty of the American Academy of Asian Studies.
John Llewelyn
John Llewelyn (born 1928) is a Welsh-born British philosopher whose extensive body of work, published over a period of more than forty years, spans the divide between Analytical and Continental schools of contemporary thought.
 He has conjoined the rigorous approach to matters of meaning and logic typical of the former and the depth and range of reference typical of the latter in a constructive and critical engagement with the work of Jacques Derrida and Emmanuel Levinas.
Kate Horsley
Kate Horsley (born 1952) is the pen name of Kate Parker, an author of numerous works of historical fiction three of which are rooted in the Old West.
 Parker is a professor of English at Central New Mexico Community College in Albuquerque.
 She has a lifelong flirtation with Zen after reading Alan Watts.
 Her published novels include:
Robbie Stamp
Robbie Stamp (born 1960) was the CEO of The Digital Village, a position that came about partly because of his friendship with author Douglas Adams, whose works inspired the site.
 Stamp was also the executive producer of the movie version of "The Hitchhiker's Guide to the Galaxy".
Kate Horsley (UK author)
Kate Horsley is the author of two novels, "The American Girl" and "The Monster’s Wife".
 Most of her short and long fiction, including "The American Girl", has been within the crime fiction genre, although her début novel, "The Monster’s Wife", is historical gothic fiction.
 Horsley is a co-editor (with her mother, Lee Horsley) of crime fiction review site crimeculture.com.
Petar II Petrović-Njegoš
Petar II Petrović-Njegoš (, ] ; 13 November [O.S. 1 November] 1813  – 31 October [O.S. 19 October] 1851 ), commonly referred to simply as Njegoš, was a Prince-Bishop ("vladika") of Montenegro, poet and philosopher whose works are widely considered some of the most important in Montenegrin and Serbian literature.

Answer: 16 November 1973