The money invested in science is a slippery subject. While direct funds, such as those made available through the National Science Foundation, are rather scarce, funding through various government agencies (Defense, Agriculture, Energy, NASA) and through private sources amounts to hundreds of billions of dollars. How much of this goes to fundamental research and how much to applied science is not very clear, as even the distinction between fundamental and applied is less and less clear.

Ernst Mach. The Science of Mechanics (1883). Trans. T.J.
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Henri Poincaré. The Foundations of Science (1909). Trans. G.B.
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N.P. Cambell. Foundations of Science (1919). New York: Dover, 1957.

Bas C. van Fraasen. The Scientific Image. Oxford: Clarendon
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Richard Dawkins. The Selfish Gene. New York: Oxford University
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Elan Moritz, of the Institute for Memetic Research, provides the historic and methodological background to the subject in Introduction to Memetic Science.

E.O. Wilson. Sociobiology: The New Synthesis. Cambridge:
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Mihai Nadin. Mind-Anticipation and Chaos (from the series
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