1. Introduction to Cognitive Science Lecture #1 : INTRODUCTION Joe Lau Philosophy HKU

2. What is Cognitive Science? An interdisciplinary science of mind and behavior. It is a science It studies mind and behavior It is interdisciplinary Cognitive science theories and explanations often invoke computations and representations.

3. Mental Phenomena From the mundane... Perception, language, reasoning, action,... To the abnormal and the bizarre Cognitive impairments ( e.g. autism, prosopagnosia, Cotard delusion, … ) and non-human species Animal cognition

4. Find your child... Cape Cross, Namibia

5. Why computation? Assumption #1 : Mental processes involve complex information processing. Assumption #2 : Complex information processing requires computations. Conclusion : Computations are necessary for explaining mental processes.

6. What is computation? Computation is (roughly) a rule- governed process which manipulates representations. We have strong evidence that the brain is capable of carrying out massively parallel computations.

7. Mental representations MR = objects or states in the brain which encode information. Don’t confuse : TREE

8. Mundane reminder “Tree” is a word, a representation. It is a representation of a tree, a living thing, not a representation of “tree”. TREE represents

9. Role of mental representations Information has to be physically encoded so that they can be manipulated. Memory / knowledge : storing representations Thinking : causal sequence of representations Two examples

10. Visual Perception Topographical representation of visual stimulus in area V1

12. Syntactic Disambiguation “We shall discuss violence on TV.” Two interpretations : VP V NP PP Ndiscuss violence on TV P VP V NP Ndiscuss violenceNP PP on TV P

13. Three Levels of Description Three (kinds of) levels in describing a computational system : Task : what the system is capable of doing (capacities) Algorithm (software) : which computation procedures are used Implementation (hardware) : how the computations are implemented

14. Why Cogsci is Interdisciplinary Horizontal and vertical diversity in mental capacities : The mind can carry out lots of different tasks in different areas. Each of these capacities can be studied at different levels. Cogsci and psychology

15. Relevance of cogsci Scientific understanding Education Psychiatry IT, AI Design of computer interface Voice recognition, data mining Cybernetics

17. Necessity and Sufficiency Computations might be a necessary part of most if not all explanations of mental processes. But computations themselves might not be sufficient (enough) to explain all mental processes. Maybe some special features of the mind are due to neuro-physiological properties. Sleep? Hormonal effects?

18. Possibility of AI AI = artificial intelligence Computations might still be sufficient for mentality even if some aspects of the human mind can only be explained neuro-physiologically.

19. Three Problems Philosophers’ three major concerns : Intentionality Consciousness Freewill

20. Intentionality Intentionality = aboutness, meaning, content Language, knowledge, reasoning, beliefs, perception The belief that 2>1 is a belief about numbers. To be explained in terms of mental representations.

21. Phenomenal Consciousness Feelings, sensations, experience Some mental states are both conscious and intentional e.g. conscious thinking

22. Freewill What is freewill? (A) Capable of making decisions + (B) ??? Presumably (A) can be explained computationally. What more is required?

23. Can computers do X? “Computers cannot have emotions / creativity / understanding / humour …” To decide whether computers can have a mental state X, we need to : Identify the conditions required for having X. Decide which of the conditions are easy / difficult to be satisfied, and how.

24. Can computers be creative? What are the preconditions for creativity? Generating ideas and hypotheses Selecting and modifying the useful ones. Both cognitive / intentional processes No in-principle obstacles?