11 September 1998HKU Scientific Roots Descartes: mind as active & reasoning Newton: reductionist explanation Darwin: competition & natural selection - shared evolutionary history

11 September 1998HKU The Beginning George Miller (1956) Noam Chomsky (1957) John McCarthy Marvin Minsky Allen Newell Herbert Simon

11 September 1998HKU The Insights Noam Chomsky: external feedback insufficient for language development. Herb Simon: problem-solving described in computational terms. George Miller: memory dissected. Roger Sperry: brain dissected.

11 September 1998HKU How is Information Represented? Logical Rules –Aristotle (Greek philosopher, 3000 years ago) –McCarthy Procedures –Newell and Simon Images Concepts, schemas, scripts –Minsky

11 September 1998HKU Representation Symbols Concepts Images Analogies Words Categories Rules

11 September 1998HKU Role of Representations Problem-solving –Reasoning –Decision-making –Planning

11 September 1998HKU The Central Hypothesis of Cognitive Science “Thinking can best be understood in terms of representational structures in the mind and computational procedures that operate on those structures.” Thagard, 1996

11 September 1998HKU The Computational View PROGRAM data structures + algorithms = running programs MIND mental representations + computational procedures = thinking

11 September 1998HKU Algorithms e.g. Transforming symbol structures (A B C) <-- list (data) REVERSE <-- algorithm (C B A) e.g. Making Flakey Muffins 2 cups Oat Bran Flakes 2 cups whole wheat 1 tbsp. baking powder 1/4 cup honey 1-1/2 cups milk Mix dry ingredients. Blend liquid ingredients in separate bowl. Stir gently making sure all flakes are coated evenly. Bake at 375 F for minutes.

11 September 1998HKU Doing Simple Math How does a person add 17 and 12? –Retrieve a value from memory? –Break numbers down? –Add them in parallel?

11 September 1998HKU Counting Objects How many? H H H

11 September 1998HKU Counting Objects How many? H H H H H H