MTC

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The Layered Protocol Theory of Dialogue
M. M. Taylor
Martin Taylor Consulting
mmt_at_mmtaylor.net
MTC
Control Systems Group, Crieff Hills, 2005
2
The structure of a dialogue the originators view
A dialogue involves two people an originator we
call Oliver and a recipient we call
Rachel Oliver initiates the dialogue because he
has a reference for his perception of Rachel.
This reference is for Rachel to understand
something or to perform some action. From
Olivers point of view, the dialogue is
successful when Oliver perceives Rachel to
understand or to act according to his reference
value for his perception of her. Olivers
reference state for his perception of Rachel is
called the Primal Message
MTC
Control Systems Group, Crieff Hills, 2005
3
The structure of a dialogue the recipients view
The recipients view of the dialogue is more
complex. Rachel perceives that Oliver wants to
convey a message (i.e. to have her understand
something or to act in some way). This perception
may be tantamount to a disturbance of one or more
controlled perceptions, such as to perceive
Oliver to be satisfied with her understanding or
her actions. If Olivers attempt to initiate a
dialogue does not disturb any of Rachels
controlled perceptions, she will not act, and
Olivers Virtual Message will not influence his
perception of her state (at least not in respect
of that Primal Message).
MTC
Control Systems Group, Crieff Hills, 2005
4
The structure of a dialogue both views
Rachels perception Olivers satisfaction has
been disturbed, and since she is controlling that
perception, she will act in a way that Oliver can
perceive. She will acknowledge Olivers
initiation. Oliver sees this as feedback.
MTC
Control Systems Group, Crieff Hills, 2005
5
The structure of a dialogue the external
Analysts view
The external analyst cannot see the reference
perceptions of either party. Nor, really, can the
analyst see either the intended or the received
meanings of the Virtual Message or the
Acknowledgment. In most cases, the Analyst can
observe the physical manifestations of the
Virtual Message and the Acknowledgment in the
communication medium (e.g. the sounds of the
voices, the gestural movements of hands and
face, etc.), but not the perceptual effects of
those physical manifestations on the dialogue
partners.
MTC
Control Systems Group, Crieff Hills, 2005
6
The structure of a dialogue the external
Analysts view of Layers and Protocols.
Oliver, Rachel, and the Analyst are in the same
boat. They can only see or hear the actions of
the dialogue partner, and must infer their
intent. But Oliver and Rachel can apply The
Test, whereas the Analyst can only observe.
Oliver
Rachel
Virtual Message
Acknowledgment
Translations
Translations
Physical media
MTC
Control Systems Group, Crieff Hills, 2005
7
The structure of a dialogue the external
Analysts view of Layers and Protocols.

• What does Rachels acknowledgment do? There are
  several possibilities.
• It brings Olivers perception to its reference
  value (the Primal Message has been passed). In
  other words, Oliver perceives that Rachel has
  understood or acted as he wished.
• 2. It allows Oliver to perceive that Rachel has
  not understood, but also that Rachel is prepared
  to receive the Primal Message. Or not, as the
  case may be.

MTC
Control Systems Group, Crieff Hills, 2005
8
The structure of a dialogue the external
Analysts view of Layers and Protocols.

• What does Rachels acknowledgment do? More
  possibilities.
• 3. It brings Rachels perception to its reference
  value (Oliver is satisfied). In other words,
  Rachel perceives that its effect on Oliver allows
  her to perceive that the Primal Message has been
  passed.
• 4. It serves as a Primal Message of another kind,
  from Rachel to Oliver, with the intent of
  allowing Oliver to perceive in what way Rachel
  has not completely received the Primal Message.

MTC
Control Systems Group, Crieff Hills, 2005
9
The structure of a dialogue the external
Analysts view of Layers and Protocols.

• Note possibility 4 Rachels acknowledgment
  serves as a Primal Message of another kind, from
  Rachel to Oliver, with the intent of allowing
  Oliver to perceive in what way Rachel has not
  completely received the Primal Message.
• At this point, the analyst should see two
  simultaneous Primal Messages being passed, one
  from Oliver to Rachel, about what he wants her to
  understand or do, and one from Rachel to Oliver,
  about the current state of her understanding of
  his initial Primal Message. Rachels message is a
  Protocol Message, which Oliver can acknowledge.
• Protocol messages support the transmission of the
  content of Olivers Primal Message, by letting
  Oliver know what Rachel believes about her
  understanding. Protocol messages from Oliver to
  Rachel help Rachel to perceive what Oliver
  believes about the current state of the
  transmission of the Primal Message.
• Other virtual messages, which may be embodied in
  the same physical manifestation as are the
  Protocol messages, allow Oliver to reduce the
  error in his perception of Rachel, for which the
  reference value is the initial Primal Message.

MTC
Control Systems Group, Crieff Hills, 2005
10
The structure of a dialogue the external
Analysts view of the General Protocol Grammar
(GPG)
Our early work on Layered Protocol Theory
(before, say, 1990) was designed not to explain
human communication, but to ease Human-Computer
Interaction. We developed a General Protocol
Grammar, which was intended to be applicable at
any level in the translation hierarchy between
the top-level Virtual Message and its
Acknowledgment and their bottom-level physical
manifestations. We found, however, that
essentially the same GPG described real human
dialogue. Heres a small, but important, part of
it, drawn in the intelligible, but misleading
form of a flow chart. It is misleading because it
carries the implication that the dialogue is in
some one state and changes state as a consequence
of actions by one party after the other in
alternation. A real dialogue isnt like that.
MTC
Control Systems Group, Crieff Hills, 2005
11
Layers
Oliver
Rachel
Virtual Message
Acknowledgment
Acknowledgment
Virtual Message
Translations
Translations
Physical media
MTC
Control Systems Group, Crieff Hills, 2005
12
Layers and Protocols
One Virtual Message
A supporting (lower-level) Virtual Message
Primary
Normal Ack
Start
End
Edit
Accept Change
Problem
Problem
Resolution
MTC
Control Systems Group, Crieff Hills, 2005
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Layers and Protocols
To pass a complex message (e.g. the General
Theory of relativity) may take years and
thousands of supporting messages that involve
words and pictures. To pass a simple message
(e.g. Im skeptical) may take no more than a
slight lift of an eyebrow, with no words being
involved at all. In fact, some messages can be
conveyed by a failure to act at all.
Concepts
Supporting concepts
Words and Gestures
Sound and Sight
MTC
Control Systems Group, Crieff Hills, 2005
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Layers and Protocols
The instantiations of the various elements of the
GPG are likely to be different from level to
level. Repeated use of the Edit loop is
probable if the Primal Message is a complex
concept. Almost all the arcs will be unused or
have null instantiations if the Primal message
is a word spoken clearly in a mutually understood
language.
Concepts
Supporting concepts
Words and Gestures
Sound and Sight
MTC
Control Systems Group, Crieff Hills, 2005
15
The Layered Protocol Theory of Dialogue
M. M. Taylor
Martin Taylor Consulting
mmt_at_mmtaylor.net
MTC
Control Systems Group, Crieff Hills, 2005