Proof Theory for Narrative Structure

10 min talk on representing narrative structure for FDG doctoral consortium.

Transcript

1. Proof Theory for
   Narrative Structure
   Chris Martens
   
   Carnegie Mellon University
   
   Computer Science Department
   
   !
   Foundations of Digital Games 2015
   
   Doctoral Consortium, Sunday, June 21
   

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2. Proof Theory for
   Narrative Structure
   Chris Martens
   
   Carnegie Mellon University
   
   Computer Science Department
   
   !
   Foundations of Digital Games 2015
   
   Doctoral Consortium, Sunday, June 21
   

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3. Research Goal
   Bridge narrative theory with systems understanding
   
   via conceptual and computational tools.
   3
   

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4. resource flow
   
   physics
   
   puzzles
   
   emergent behavior
   
   strategic choices
   characters
   
   backstory
   
   plot
   
   dialogue
   
   moral choices
   System and Narrative
   4
   

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5. resource flow
   
   physics
   
   puzzles
   
   emergent behavior
   
   strategic choices
   characters
   
   backstory
   
   plot
   
   dialogue
   
   moral choices
   System and Narrative
   5
   

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6. Important research
   subquestion:
   How do we understand narrative structure?
   6
   If narratives have several parts,
   
   what are they,
   
   and how do they connect to one another?
   

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7. Important research
   subquestion:
   How do we understand narrative structure?
   7
   If narratives have several parts,
   
   what are they,
   
   and how do they connect to one another?
   

   View Slide

8. Important research
   subquestion:
   How do we understand narrative structure?
   8
   If narratives have several parts,
   
   what are they,
   
   and how do they connect to one another?
   

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9. Take 1: Potential Narratives
   Twine node map
   9
   

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10. Example: Three Little Pigs
    There are three little pigs and a big bad wolf.
    
    !
    One pig builds a house out of straw, one builds a house out of sticks
    and one builds a house out of bricks.
    
    !
    The big bad wolf visits the straw house, blows the house down, and
    eats the pig.
    
    !
    The big bad wolf visits the stick house, blows the house down, and
    eats the pig.
    
    !
    The big bad wolf visits the brick house and fails to blow it down.
    10
    

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11. NARRATIVE STRUCTURE
    Twine node map
    11
    

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12. NARRATIVE STRUCTURE
    Twine node map
    12
    

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13. One of three little pigs builds a house out of straw.
    
    !
    A wolf appears at the door...
    
    !
    "Little pig, little Pig, let me come in."
    
    "No, no, not by the hair on my chinny chin chin."
    
    "Then I'll huff, and I'll puff, and I'll blow your house in.."
    
    !
    And she does, and she eats the little pig!
    One of three little pigs builds a house out of bricks.
    
    !
    A wolf appears at the door...
    
    !
    "Little pig, little Pig, let me come in."
    
    "No, no, not by the hair on my chinny chin chin."
    
    "Then I'll huff, and I'll puff, and I'll blow your house in.."
    
    !
    But she can’t!
    One of three little pigs builds a house out of sticks.
    
    !
    A wolf appears at the door...
    
    !
    "Little pig, little Pig, let me come in."
    
    "No, no, not by the hair on my chinny chin chin."
    
    "Then I'll huff, and I'll puff, and I'll blow your house in.."
    
    !
    And she does, and she eats the little pig!
    13
    

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14. Take 2: Timelines
    xkcd.com/657
    14
    

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16. NARRATIVE STRUCTURE
    Twine nodemap expands to many possible stories
    
    =
    
    simultaneous representation of multiple narratives
    16
    

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17. NARRATIVE STRUCTURE
    LOTR graph expands to multiple “tellings”/directorial choices
    
    =
    
    representation of multiple simultaneous narratives
    17
    

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18. NARRATIVE STRUCTURE
    choice vs. simultaneity
    18
    

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19. Linear Logic:
    A logic of choice & simultaneity
    - A is simultaneous with B
    
    !
    - choice between A and B
    19
    

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20. Linear Logic
    - it is possible to transform A into B
    20
    

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21. Potential Narrative version of Three Little Pigs
    21
    Possible to prove:
    

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22. Multiple Timelines version of Three Little Pigs
    22
    

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23. Multiple Timelines version of Three Little Pigs
    23
    Possible to prove
    

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24. Simultaneity in Three Little Pigs
    24
    RKI
    RKI
    RKI
    YQNH
    UVTCY
    DTKEMU
    UVKEMU
    UVTCYAJQWUG
    UVKEMAJQWUG
    DTKEMAJQWUG
    T
    
    DWKNFUVTCY
    JQWUG
    T
    
    DWKNFUVKEM
    JQWUG
    T
    
    YQNHXUDTKEMU
    T
    
    DWKNFDTKEM
    JQWUG
    T
    
    YQNHXUUVKEMU
    T
    
    YQNHXUUVTCY
    YQNH
    YQNH
    DTKEMAJQWUG
    

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25. Reed/Garbe “combinatorial narrative”
    — Jacob Garbe, Gamasutra post “The Narrative Engine Driving Ice-Bound: A
    Novel of Reconfiguration”
    25
    

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26. monolithic story state
    
    vs
    
    composable story components
    26
    

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27. Proof theory makes a useful unifying formalism
    
    for narrative structure and interactive systems.
    27
    Research Hypothesis:
    

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28. narrative generation [Martens et al., INT 2014]
    
    !
    prototyping language for interactive narrative mechanics
    
    [Ceptre, publication in progress]
    
    !
    analysis tools (discovering possible stories and state invariants)
    
    [work in progress]
    Evidence of usefulness:
    28
    

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29. Thesis Statement
    Linear logic and its theory of proof are a useful conceptual and
    computational framework for bridging narrative theory with
    systems understanding.
    29
    

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30. CYO Discussion
    Works of interactive fiction with compositional state (slide 31)
    !
    Turning these ideas into a programming language (slide 33)
    !
    Related work in story validation (slide 36)
    !
    Related work in game description languages (slide 38)
    !
    How does a proof represent a story? (slide 42)
    30
    

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31. Discussion Slides
    31
    

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32. Other IF with multiplicative state
    32
    

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33. Other IF with multiplicative state
    33
    

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34. Ceptre
    34
    stage = set of rules
    
    r : A -o B
    
    !
    program =
    
    set of stages
    
    + stage control flow
    
    + initial state
    
    6 6¶
    6R6¶
    
    U6R6¶
    
    
    Q
    
    /RJLF3URJUDP
    LQLWLDOVWDWH
    

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35. Ceptre
    35
    

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36. 36
    Ceptre
    

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37. Related Work
    37
    

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38. Related Work
    38
    

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39. Related Work
    39
    

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40. Related Work
    40
    

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41. Related Work
    41
    

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42. Related Work
    42
    

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43. Story Derivation for Choice-Based Three Little Pigs
    43
    

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44. Story Derivation of Simultaneity in Three Little Pigs
    44
    

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45. Thanks!
    Ceptre language:
    github.com/chrisamaphone/interactive-lp
    !
    Me (web): http://www.cs.cmu.edu/~cmartens
    !
    Me (Twitter): @chrisamaphone
    45
    

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46. other discussion points?
    Other IS concerns:
    Drama Management
    Narrative Drive
    Reactive Planning
    !
    Tellings informed by player/reader knowledge state
    (stuff like “Memento” or scenes told out-of-causal-order)
    46
    

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