The Levels Hypothesis states that there are at least three levels at which systems that exhibit intelligence can be appropriately described; namely, the Physical Level, the Symbolic or Computational Level; and the Semantic or Knowledge Level.

(a) Describe how these levels are defined and differentiated from each other.

(b) Describe the nature of the relation that holds between these levels according to this hypothesis.

(c) Assume that the hypothesis is true and state some of the implications of this hypothesis for the investigation and understanding of intelligent systems.

(d) Assume that the hypothesis is false and state some of the implications for the investigation and understanding of intelligent systems that follow if the hypothesis is false.

 * The purpose of the assignment is to provide for you an opportunity to organize your current understanding of the topic of the essay and enable you to discuss these issues. I would expect that you could usually cover the topic of the essay in 1 to 3 pages. You should minimize the use of quotations from the book, lecture or the web site and organize your own thoughts and express them as originally as possible. You should make an effort to communicate not just your conclusions but the basis for your conclusions. Where an argument is to be made be sure to clearly and explicitly communicate your argument. (The simple assertion of your opinion on a matter does not constitute an argument.)

Obviously one could, and people have, written long essays on these issues. Your answer is not expected to be definitive. It is the way in which you have organized these ideas in your mind that I am interested in; not a verbose answer.

Finally, if you wish to focus your answer on one or more aspects of the question in order to go into those aspects in more depth you may do so as long as it is apparent from your essay that you have a command of the issues raised in the essay question.