A Companion to the Philosophy of Science (Blackwell Companions to Philosophy)
W. H. Newton-Smith
This is a good collection of articles on a wide variety of major topics in the philosophy of science. Esp. good for undergraduates to get an overview of key arguments about various schools of thought, concepts, and thinkers. Given the relatively low price, the large number of pages, and the quality of (most) of the articles, it is well worth purchasing.
