This Is Metaphysics. Kris McDaniel

      1 1 http://www.mathsisfun.com/sets/venn-diagrams.html

      2 2 Whether tomatoes are fruits might seem completely trivial, but interestingly this is a question that has been addressed by no less than the Supreme Court of the United States! http://www.npr.org/blogs/money/2013/12/26/256586055/when-the-supreme- court-decided-tomatoes-were-vegetables

      3 3 If you are curious about why whales are not fish: http://scienceline.ucsb.edu/getkey.php?key=2536

      4 4 Here's what NASA has to say about Pluto: http://www.nasa.gov/audience/forstudents/k-4/stories/what-is-pluto-k4.html#.U6nCQ_ldWSo

      5 5 The concept of race is in need of retirement, according to Professor Jablonski. http://edge.org/responses/what-scientific-idea-is-ready-for-retirement

      6 6 The Stanford Encyclopedia of Philosophy is a wonderful resource. It's filled with excellent introductions. Here is the one for “race,” which I highly recommend: http://plato.stanford.edu/entries/race/

      7 7 Appiah is currently a professor of philosophy and law at New York University. His website is: http://www.appiah.net Most of his published papers are available there, including: http://appiah.net/wp-content/uploads/2010/10/The-Uncompleted-Argument-Du-Bois-and-the-Illusion-of-Race.-Critical-Inquiry-12.1.-1985.pdf This paper discusses Appiah's views on the metaphysics of race.Zack is currently a professor of philosophy at the University of Oregon. Zack's views on the metaphysics of race can be found in her book Philosophy of Science and Race (London: Routledge, 2002). Her faculty profile is here: http://philosophy.uoregon.edu/profile/nzack/

      8 8 Quayshawn Spencer is currently a philosopher at the University of Pennsylvania. His webpage, which contains many of his published papers, can be found here: https://sites.google.com/site/qnjspencer/publications

      9 9 Eli Hirsch is currently a professor of philosophy at Brandeis University: http://www.brandeis.edu/facultyguide/person.html?emplid=3b8c58f368269c9b2a81bea2caf5cd32e3d4e84a An important book by Hirsch on the subject of classification (among other metaphysical topics) is Dividing Reality (New York: Oxford University Press, 1993).

      10 10 This puzzle appeared in chapter 3 of Nelson Goodman's book Fact, Fiction, & Forecast (Cambridge, MA: Harvard University Press, 1995).

      11 11 http://monist.oxfordjournals.org/content/monist/94/2/157.full.pdf

      12 12 https://global.oup.com/academic/product/resisting-reality-9780199892624?cc= us&lang=en&#

      13 13 http://plato.stanford.edu/entries/lewis-metaphysics/natural-distinction.html