Slides for the session run at Systems Thinking Sheffied 2 in February 2010.

1. Systems Thinking Sheffield
February 2011
Why Won’t My Car Start?
Exploring cause-and-effect in systems and
organisations
Ashley Moran
Creative Commons Attribution-Noncommercial-Share Alike
2.0 UK: England & Wales License PatchSpace Ltd

2. A warm-up exercise

3. Task: Using “because”
Take and index card
Write a complete sentence that includes
the word “because”
It could be a generic statement
Maybe something that happened to
you recently

4. Task: Using “because”
Form groups of 2 or 3
Take each sentence in turn and ask the
author questions about the reasoning
Remember:
do ask questions
don’t jump to conclusions
don’t tell the other person they’re
“wrong”

5. Task: Using “because”
What did you learn?
Were any of the original statements
less watertight that you thought?

6. Task: Using “because”
(This task was inspired by one I read
about Goldratt doing at the start of a
meeting)

7. Types of logic

8. Sufficiency vs Necessity
Necessity logic
IN ORDER TO stay alive WE MUST
drink water
IF WE DO NOT drink water WE
CANNOT stay alive
What are the assumptions (the tacit
“because”)?

9. Sufficiency vs Necessity
Sufficiency logic
IF I drink water now THEN I will not be
thirsty for a while
IF I am thirsty THEN I cannot have
drunk water recently
What are the assumptions (the tacit
“because”)?

10. Sufficiency with “
and”

11. Sufficiency with “
and”
Read as:

12. Sufficiency with “
and”
Read as:
IF there is a
lightbulb in the
circuit

13. Sufficiency with “
and”
Read as:
IF there is a
lightbulb in the
circuit
AND there is a
battery in the
circuit

14. Sufficiency with “
and”
Read as:
IF there is a
lightbulb in the
circuit
AND there is a
battery in the
circuit
AND the circuit is
unbroken

15. Sufficiency with “
and”
Read as:
IF there is a
lightbulb in the
circuit
AND there is a
battery in the
circuit
AND the circuit is
unbroken
THEN the lightbulb is
on

16. Sufficiency with “or”

17. Sufficiency with “or”
Read as:

18. Sufficiency with “or”
Read as:
IF I am standing in
the rain

19. Sufficiency with “or”
Read as:
IF I am standing in
the rain
AND I have no
protection from the
elements

20. Sufficiency with “or”
Read as:
IF I am standing in
the rain
AND I have no
protection from the
elements
... OR I fell in a
swimming pool

21. Sufficiency with “or”
Read as:
IF I am standing in
the rain
AND I have no
protection from the
elements
... OR I fell in a
swimming pool
THEN I am wet

22. Expressing
reservations about
cause-effect logic
trees

23. Expressing reservations
People are emotionally attached to
things they have worked on
People can take criticism of their work
as a personal affront
It’s very important to tackle cause-and-
effect logic problems as “you and me
versus the tree” not as a matter of
personal opinion

24. The Prime Directive
"Regardless of what we discover, we
understand and truly believe that
everyone did the best job they could,
given what they knew at the time,
their skills and abilities, the resources
available, and the situation at hand."
Norm Kerth, Project Retrospectives:
A Handbook for Team Reviews
Often used by “Agile” soft ware teams

25. Expressing reservations

26. Expressing reservations
Is anything wrong
with this statement?

27. Expressing reservations
Is anything wrong
with this statement?
Reser vation: Clarity

28. Expressing reservations

29. Expressing reservations
Is anything wrong
with this statement?

30. Expressing reservations
Is anything wrong
with this statement?
Reser vation: Entity
Existence

31. Expressing reservations
Is anything wrong
with this statement?
Reser vation: Entity
Existence
Incomplete
statement

32. Expressing reservations
Is anything wrong
with this statement?
Reser vation: Entity
Existence
Incomplete
statement
Compound
statement

33. Expressing reservations
Is anything wrong
with this statement?
Reser vation: Entity
Existence
Incomplete
statement
Compound
statement
Non-existent fact

34. Expressing reservations

35. Expressing reservations
Is anything wrong
with this statement?

36. Expressing reservations
Is anything wrong
with this statement?
Reser vation:
Causality Existence

37. Expressing reservations

38. Expressing reservations
Is anything wrong
with this statement?

39. Expressing reservations
Is anything wrong
with this statement?
Reser vation: Cause
Insufficiency

40. Expressing reservations
Is anything wrong
with this statement?
Reser vation: Cause
Insufficiency
What about day/
night?

41. Expressing reservations

42. Expressing reservations
Is anything wrong
with this statement?

43. Expressing reservations
Is anything wrong
with this statement?
Reser vation:
Additional Cause

44. Expressing reservations
Is anything wrong
with this statement?
Reser vation:
Additional Cause
What about the
windows?

45. Expressing reservations

46. Expressing reservations
Is anything wrong
with this statement?

47. Expressing reservations
Is anything wrong
with this statement?
Reser vation: Cause-
Effect Reversal

48. Expressing reservations
Is anything wrong
with this statement?
Reser vation: Cause-
Effect Reversal
Watch out! These
can be very subtle

49. Expressing reservations

50. Expressing reservations
Is anything wrong with these statements?

51. Expressing reservations
Is anything wrong with these statements?
Reser vation: Predicted Effect Existence

52. Expressing reservations
Is anything wrong with these statements?
Reser vation: Predicted Effect Existence
What else would the proposed causes imply?

53. Expressing reservations

54. Expressing reservations
Is anything wrong
with this statement?

55. Expressing reservations
Is anything wrong
with this statement?
Reser vation:
Tautology

56. Expressing reservations
Is anything wrong
with this statement?
Reser vation:
Tautology
How do you know
the rock is tiger-
repellant?

57. Expressing reservations
Is anything wrong
with this statement?
Reser vation:
Tautology
How do you know
the rock is tiger-
repellant?
Dues owed to Lisa
Simpson for this one

58. Categories of reservation
Clarity
Entity Existence (atomic, valid)
Causality Existence (logic doesn’t follow)
Cause Insufficiency (something missing)
Additional Cause (alternative explanation)
Cause-Effect Reversal
Predicted Effect Existence
Tautology (circular reasoning)

59. Current Reality
Trees

60. Current Reality Trees
Part of the Theory of Constraints (TOC)
body of knowledge
Theory of Constraints enabled people to
optimise a system around a process
bottleneck (as in the novel The Goal)
Production capability increased
Eventually the constraint became not
production, but (management) policies
and assumptions

61. Current Reality Trees
Current Reality Trees
use cause-effect logic trees
to explain the current reality
of a system

62. Current Reality Trees
If you have a goal in mind for the
system, you can identify Undesirable
Effects (UDES) with respect to that goal
We’re glossing over the (more
important?) stage of defining the goal
and its necessary conditions

63. An example CRT

64. An example CRT
Note:

65. An example CRT
Note:
UDEs are determined
relative to a goal

66. An example CRT
Note:
UDEs are determined
relative to a goal
Is low quality
actually
undesirable? Says
who?

67. An example CRT
Note:
UDEs are determined
relative to a goal
Is low quality
actually
undesirable? Says
who?
Watch for the
feedback loop

68. An interactive exercise
Why are the monkeys hungry?

69. Warning
This is a trial run of the session
You’re the experiment, not the monkeys
Hide any bananas you may have on your
person

70. The situation
You’ve been brought in to manage a room
full of monkeys
Your assume the monkeys want to be
happy, and that to be happy they must
be well fed
Let’s look at some facts available
Let’s ask “why?” and “what happens
if?” to explore the situation
(I know the answers)

71. Drawing a tree
This slide is a placeholder for the time
we spend drawing a Current Reality
Tree for the “monkey story”

72. Retrospective
What did we learn?

73. Further reading
It’s Not Luck - Eliyahu M Goldratt
The Logical Thinking Process - H William
Dettmer
Thinking Processes Including Strategy &
Tactics Trees (ebook) - Lisa J Scheinkopf
Flying Logic (tree soft ware) - developed
by Sciral