The Architecture of Jumbo Response Essay

Part 1 - Relatively Short Answer

  1. What is the main topical theme of the chapcter, and why is it of signifincance. (Hint: Look to the subtitle of the preface, and consider what you read in the preface.)
    2. The main topical theme of this chapter is that cognition in humans is likely to arise from subtle unconscious parallelized neural processes which give rise to conscious sequential thought.
  2. Do your best to describe (in more than two words) the long-term goal shared by Jumbo and some of Hofstadter's other AI projects.
    3. The goal of Jumbo is to accomplish a task done by the human mind using methods that are analogous to the methods used by the mind.
  3. What is Herb Simon's perspective on Hofstadter's architecture and the aspect of cognition that it purports to study?
    4. Herb Simon is of the perspective that the interesting parts of neural processes happen at a macro scale time wise, and therefore thinks that Hofstadter's analysis of the unconscious parallel underpinings of cognition will be fruitless.
  4. What does Hofstadter claim is the core mystery of all of intelligence?
    5. The core mystery of intelligence as purported by Hofstadter is the syntactic-semantic transition, or where physically sensed phenomena are converted to their mental representations.
  5. What is the "concrete purpose of Jumbo?
    6. Jumbo's concrete purpose is to be a machine that is able to play the game "Jumble".
  6. Hofstadter states that Jumbo is a building program. Explain what he means by this.
    7. Jumbo is a building program in that it takes elementary building blocks (ie. letters, syllables, etc.) and puts them together to form higher order structures.
  7. What is the "serious purpose" of Jumbo?
    8. In seriousness, Jumbo's true purpose is to recreate the way in which humans analyze and process data.
  8. What is the significance of Jumbo's task domain?
    9. The significance of Jumbo's task domain is that it represents the way in which humans are able to unconsciously juggle mental representations.
  9. Hofstadter suggests that in any type of perception, much back-and-forth motion must occur. What does he mean by this?
    10. Hofstadter's claim of a back-and-forth motion being necessary for perception is meant to describe the way in which we must build and destruct the mental structures we use to understand something that we perceive multiple times before coming to a concrete perception of the target.
  10. Jumbo rests on two basic analogies. One is the way that complex molecules are constructed inside a living cell; the other is to the way that bonds of human friendship or romance are formed in a chaotic world.
    1. Describe the biological analogy.
      2. A cell constructs proteins in multiple stages, similar to Jumbo. It encodes the initial template of DNA to RNA, which is then used to transform molecules into amino acids, which combine to form polypeptide chains, which can come together to form proteins.
    2. Describe the sociological analogy.
      3. Similarly, romantic relationships start off as a mere meeting between two people, and moves on to a stage in which both individuals are curious about each other, then on to a dating stage that can eventually lead to marriage.
  11. Jumbo is a parallel processing system. Describe the nature of its parallelism.
    12. Parallelism describes a method for accomplishing a task in which a number of the subtasks which make up the task are worked on in tandem.
  12. Central to Hofstadter's modeling of the unconscious juggling of mental objects are the notions of "sparks" and "affinities".
    1. Describe, in words and by means of examples, what Hofstadter means by "sparks".
      2. "Sparks" are a term that Hofstadter uses to describe when two elements in Jumbo are coupled together after coming in contact.
    2. Describe, in words and by means of examples, what Hofstadter means by "affinities".
      3. Their chance of "sparking" depends upon their "affinity" with one another, which is how likely they are to be paired with each other for any type of pairing.
  13. What is a codelet?
    14. A codelet is a small piece of code that takes care of a specific task and can be placed in a queue-like structure where it waits to be executed.
  14. It is the queue-like structure in which all codelets are placed while they are waiting to be run. What is it called?
    15. The queue-like structure where codelets wait to be executed is called the "Coderack" by Hofstadter.
  15. Are codelets seleceted for execution in a deterministic fashion? Elaborate some on your "yes/no" answer.
    16. Codelets are not selected in a deterministic fashion but are instead selected at random with a bias towards codelets having higher priority.
  16. Is all processing in programs that adhere to Hofstadter's architecture implemented via codelets? Elaborate some on your "yes/no" answer.
    17. Not all processing in programs adhering to Hofstadter's architecture needs be implemented via codelet. Hofstadter posets the possibility of a self monitoring system in which the program watches it's state in order to intercede should loop-behavior begin to emerge.

Part 2 - Very Short Answer

  1. When a codelet is run, it ...
    1. is taken off the "queue"
    2. can cause changes to the "knowledge base"
    3. may place follow-up codelets onto the "queue"
    4. all of the above
    4
  2. The self-propagating nature of codelets enables lengthy processes to be carried out in small disjoint steps, each step setting up its own possible continuation. It resembles the way that long chains of chemical reactions get carried out in independent small steps in the cell. (TRUE or FALSE)
    3. TRUE
  3. In Prolog, processing is carried out by means of rules which operate on the knowledge base. By analogy, in Hofstadter's architecture, processing is carried out by codelets that operate on the BLANK. Fill in the BLANK!
    4. Cytoplasm
  4. Intelligence in programs that exploit Hofstadter's architecture, if indeed they have any, clearly has not been directly programmed; rather, it emerges as a statistical consequence of the way that many small program-fragments interact with each other. (TRUE or FALSE)
    5. TRUE
  5. Intelligence in Jumbo and Copycat and other such programs is like a chess program that has a subtle tendency, but one that is crystal-clear to sufficiently keen chess observers, of ``liking to get its queen out early'' -- a tendency taking its programmers completely by surprise, as they never knowingly or explicitly put any such strategic concept into their program. (TRUE or FALSE)
    6. TRUE
  6. The phenomenon suggested in the previous question has been referred to as ...
    1. an "innocently emergent" quality by Daniel Dennett
    2. "epiphenomenon" by Dougles Hofstadter
    3. both of the above
    3
  7. Early in his discussion of Jumbo, Hofstadter indicates that its strategy is based on two analogies: Which are they? (Choose TWO!)
    1. the way that complex molecules are constructed inside a living cell (cellular biology)
    2. the way that macroscopic order emerges naturally from the statistics of microscopic disorder (statistical mechanics)
    3. the way that bonds of friendship or romance are formed in a chaotic world (sociology)
    1 and 3
  8. Later on in his discussion of Jumbo, Hofstadter indicates that a third analogy is relevant to Jumbo's strategy: Which is it? (Choose ONE!)
    1. the way that complex molecules are constructed inside a living cell (cellular biology)
    2. the way that macroscopic order emerges naturally from the statistics of microscopic disorder (statistical mechanics)
    3. the way that bonds of friendship or romance are formed in a chaotic world (sociology)
    2
  9. According to Hofstadter, the reliable emergence of macro-laws from micro-chaos could even be summarized in a metaphorical equation: thermodynamics = statistical mechanics. (TRUE or FALSE)
    10. TRUE
  10. The philosophy on which Hofstadter's architecture is based goes against the grain of traditional AI work, which seeks to find explicit rules (not emergent or statistical ones) governing the flow of thoughts. (TRUE or FALSE)
    11. TRUE
  11. Hofstadter uses the term "thinkodynamics" to refer to laws governing thoughts at their own level. (TRUE or FALSE)
    12. TRUE
  12. Hofstadter uses the phrase "statistical mentalics" to refer to the laws governing subcognitive events that form the basis of higher-level thought. (TRUE or FALSE)
    13. TRUE
  13. What corny but (hopefully) catchy equation does Hofstadter use to articulate his vision of the essential mission of AI should be in the future.
    14. thinkodynamics = statistical mentalics
  14. It was the first of Hofstadter's programs to make clear use of the architecture with which he is so closely associated. What is its name?
    15. Jumbo
  15. It is a parallel investigation of many possibilities to different levels of depth, quickly throwing out bad ones and homing in rapidly and accurately on good ones. What is it?
    16. Parallel Terraced Scan
  16. The idea articulated in the previous question was Hofstadter's, but much of it was already present in:
    1. GPS
    2. SOAR
    3. Hearsay II
    3

Part 3 - More Relatively Short Answer

  1. Say something about codelets that you find particularly interesting.
    2. I find the concept of a codelet interesting because it loosely follows the UNIX philosophy of doing one thing and doing that thing well.
  2. Say something about the coderack that you find particularly interesting.
    3. The coderack is an interesting concept because it is a way to implement a prioritized parallel process.
  3. In order of salience, most salient to least salient, write down what you think are 7 particularly salient things about Hofstadter's architecture for computationally modeling cognitive processes.
    4. My list of most salient aspects of Hofstadter's architecture from most to least salient
    1. The architecture is decentralized
    2. The architecture can self monitor
    3. The architecture has a system likened to temperature for chemical processes
    4. The codelets run independent of each other
    5. The coderack mostly just holds codelets
    6. The system allows for dynamic readjustment without starting from scratch
    7. The system may or may not model human thought