These two are my favorite (that are reasonably priced!). Samuelson is definitely a formidable thinker and lays the groundwork for much later economic thinking. http://www.amazon.com/Worldly-Philosophers-Lives-Economic-Th... (http://www.amazon.com/Worldly-Philosophers-Lives-Economic-Thinkers/dp/068486214X) http://www.amazon.com/Price-Theory-Milton-Friedman/dp/020206... (http://www.amazon.com/Price-Theory-Milton-Friedman/dp/0202060748) However if you go with the Samuelson, Fridman, and Heilbroner you'll be missing out on some key concepts relating to information and games, which are essential for understanding modern developments in economics. So, I would also look at Myerson's Game Theory http://www.amazon.com/Game-Theory-Analysis-Roger-Myerson/dp/... (http://www.amazon.com/Game-Theory-Analysis-Roger-Myerson/dp/0674341163)…
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