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GrangalanJr · 2011-07-17 · Original thread
Here are some nice introductory ones:

Mathematics: A Very Short Introduction (Tim Gowers):

The Language of Mathematics: Making the Invisible Visible (Keith Devlin):

What is Mathematics?: An Elementary Approach to Ideas and Methods (Richard Courant):

They give brief but interesting glimpses into several areas of higher math, so they could help you decide what you want to pursue in more depth.

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