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2. Anscombe, G. E. M. (1958) Intention. Oxford: Blackwell.
3. Barrett, William (1958) Irrational Man. Garden City, NJ: Doubleday.
4. Bateson, Gregory (1972) Steps to an Ecology of Mind. New York: Ballantine.
5. Bergson, Henri (1911) Creative Evolution. New York: MacMillan.