16 december: The truthmaking argument for the existence of properties
To read:
Devitt, Michael, 1980. "'Ostrich Nominalism' or 'Mirage Realism'". Pacific Philosophical Quarterly 61: 433-439 (in Mellor / Oliver 1999)
Armstrong, David M., 1980. "Against 'Ostrich' Nominalism: A Reply to Michael Devitt", Pacific Philosophical Quarterly 61: 440-449. (in Mellor / Oliver 1999)
23 december: Leibniz's Law and the Puzzles of Coincidence
Buy David Lewis, On the Plurality of Worlds, Oxford: Blackwell, 1986. It's indispensible reading, for almost everything in metaphysics, and arguably the most important work of 20th century philosophy.