John Hospers was an American philosopher. In 1972 he was the first presidential candidate of the Libertarian Party, and the only minor party candidate to receive an electoral vote in the 1972 U.S. Presidential election.
Probably the best first-year intro text I've read on any subject. Read the first edition only (1956), but there are three more up into the 90's that the author assures us are almost completely re-written, making in all four different books. This is the starting point for any student.