Tania Lombrozo on Explanations (from http://www.scaruffi.com/leonardo/nov2013.html )

1. 11/5/13
What makes an explanation
beautiful? And why does it matter?
Tania Lombrozo
Department of Psychology
UC Berkeley
Richard
Dawkins
Alison
Gopnik
Daniel
Dennett
Mazharin
Banaji
Alan
Alda
Gerd
Gigerenzer
Richard
Thaler
Lisa
Randall
Scott
Atran
Eric
Kandel
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2. 11/5/13
Explanatory beauty
Simplicity
– “simplicity” 50+
– “simple” 100+
Scope
– “…the hallmark of a
deep explanation is that
it answers more than
you ask.” (Max Tegmark)
Pickiness is universal
“We are to admit no more causes of natural
things than such as are both true and sufficient
to explain their appearances.” (Newton, 1687)
"The aim of scientific explanation throughout the ages has
been unification, i.e., the comprehending of a maximum of
facts and regularities in terms of a minimum of theoretical
concepts and assumptions" (Feigl, 1970).
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3. 11/5/13
Three mysteries of explanation
1. Pickiness. Why do we have systematic
preferences for some explanations over others? In
particular, why do we value simplicity and scope?
2. Posthoc. Why do we bother explaining at all,
especially what we’ve already observed?
3. Productive. How can explanations support
learning, even in the absence of new information?
We seek explanations about what
we’ve already observed
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4. 11/5/13
Three mysteries of explanation
1. Pickiness. Why do we have systematic
preferences for some explanations over others? In
particular, why do we value simplicity and scope?
2. Posthoc. Why do we bother explaining at all,
especially what we’ve already observed?
3. Productive. How can explanations support
learning, even in the absence of new information?
Seeking explanations
fosters learning
“… the hypotheses we seek in explanation of
past observations serve again in the prediction
of future ones. Curiosity thus has survival
value, despite having killed a cat.” (Quine &
Ullian, The Web of Belief, 1970)
W.V.O. Quine
“…explanation is to theory formation as orgasm is
to reproduction — the phenomenological mark of
the fulfillment of an evolutionarily determined
drive.” (Gopnik, 2000)
Alison
Gopnik
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5. 11/5/13
“Learning by thinking”
• The self-explanation effect:
– Students who explain – even to themselves –
typically learn material more effectively and
generalize more readily to novel contexts.
F1
F2 F3
F4 F5
F7
F14
F13
F9
F12
F6 F11
F10
F2
F1
F4
F3
F5
F8
Three mysteries of explanation
1. Pickiness. Why do we have systematic
preferences for some explanations over others? In
particular, why do we value simplicity and scope?
2. Posthoc. Why do we bother explaining at all,
especially what we’ve already observed?
3. Productive. How can explanations support
learning, even in the absence of new information?
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6. 11/5/13
Thought experiments
A demonstration
Joseph
Williams
75% Body Pattern
100% Foot Pattern
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7. 11/5/13
Design overview
Introduction
Explain
vs
Control
Study
Exp 1: Explain vs. Describe
Exp 2: Explain vs. Think Aloud
Exp 3: Explain vs. Free Study
Glorp
or
Drent?
Categorization
Differences?
Explicit report
100% Foot Pattern
75% Body Pattern
Other
Proportion Discovering
100% Pattern
Explanation promotes discovery of
broad patterns
0.5
Control
Explain
0.4
0.3
0.2
0.1
0
Describe
N = 150
Think Aloud
N = 240
Free Study
N = 120
Williams & Lombrozo (2010), Cognitive Science
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8. 11/5/13
What about young kids?
Blicket
Detector
Caren
Walker
Joseph
Williams
Alison
Gopnik
Training: What makes it go?
Explain: “Why did
this one make my
machine play
music?”
Blicket
Detector
Control: “What
happened to my
machine when I
put this one on?”
Green+ & Yellow-  100% pattern
Red+ & White-  75% pattern
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9. 11/5/13
Testing: Pick a rule
GREEN versus RED.
“Which one will make my machine turn on?”
Green+ & Yellow-  100% pattern
Red+ & White-  75% pattern
Proportion of choices
favoring 100% pattern
Explanation favors broader rules
…even in preschool-aged children
1
0.8
0.6
0.4
0.2
0
Control Explain.
.
Walker, Williams, Lombrozo, & Gopnik (2012)
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10. 11/5/13
“Learning by thinking”
F1
F7
F2 F3
F4 F5
F14
F13
F12
F6 F11
F1
F2 F3
F4 F5
F7
F14
F13
F9
F12
F6 F11
F10
F8
F2
F1
F9
F4
F10
F3
F5
F8
<
F1
F2 F3
F4 F5
F7
F14
F13
F9
F12
F6 F11
F10
F8
Three mysteries of explanation
1. Pickiness. Why do we have systematic
preferences for some explanations over others? In
particular, why do we value simplicity and scope?
2. Posthoc. Why do we bother explaining at all,
especially what we’ve already observed?
3. Productive. How can explanations support
learning, even in the absence of new information?
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11. 11/5/13
These mysteries are related
Simp
licity
Explanation
Scop
e
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12. 11/5/13
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13. 11/5/13
Tania Lombrozo
Department of Psychology
UC Berkeley
cognition.berkeley.edu
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