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Coming to Know That You Know, How You Know,and What You Know
Liz RobinsonKeele University and Birmingham University, [email protected]@bham.ac.uk
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3 interlinked sections:
I. Coming to know that you know –Implicit to explicit representations of knowledge
II. Coming to know how you know –Deliberate seeking of informative knowledge sources
III. Coming to know what you know –Considering reality within a context of possibilities
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I. Coming to know that you know –Implicit to explicit representations of knowledge
On what grounds do we impute knowledge or understandingto the child?What do we expect her to do to demonstrate knowledge?
Whether or not the child demonstrates knowledge or understanding of a concept depends on the output required.
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Example 1: Assuming object permanence
•Objects continue to exist in space and time even when out ofperceptual contact•A well-adapted invention not a discovery•Wired in or constructed?•If constructed over what time-span?
•What must infant do to demonstrate she assumes object permanence?
-Piaget (1954): search for a hidden object. Success at 10 to 18 months
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Baillargeon (1987) 3,4,5 mth infantsDoes baby look longer at an impossible event - a solid object apparently moving through the space occupied by another solid object?
Baby Possible events: (i) drawbridge stops at barrier(ii) no barrier
Impossible event:Drawbridge goes through space occupied by barrier
Drawbridge experiment
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Spelke (1994) Infants 4 mths. Looking time measure.
Ball seen moving behind occluder.
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Possible eventsImpossible events Ball appears to have moved through space occupied by barrier.
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4 month olds look longer at impossible events.
Similar results when ball dropped behind screen and then screen removed to reveal ball has either landed on shelf (possible) or below shelf (impossible) event.
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Hood, Carey & Prasada (2000)
Search versions of Spelke’s tasks
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• Ball dropped behind screen• Screen removed• Child retrieves ball
Familiarise with no shelf condition, then introduce shelf with cups on shelf and below shelf. 2 yr olds repeatedly search in lower cup.
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Baillargeon, Spelke: looking times suggest early knowledge (4mths)
Piaget, Hood: search times suggest late knowledge (12-24 mths)
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Similar differentiation at later age in different domain – Theory of mind
The commonsense framework we use to makesense of people’s behaviour – desires, beliefs, intentions.
Adults differentiate what somebody thinks is true, from what is really true. We treat people as if they have an internalrepresentation of reality which can be inaccurate.
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Standard test of false belief understanding(Wimmer & Perner, 1983)
Maxi puts his ball in the red box.Maxi leaves the scene
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Dad moves the ball to theblue boxMaxi doesn’t see Dad move the ballMaxi doesn’t know the ball is in the blue box now.
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Maxi wants his ball.Where will he look first?
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'Where will Maxi look for his ball first?'
4-5 yrs: ‘Red box’- acknowledging Maxi has a false belief about ball's location.
3 yrs: ‘Blue box’ - a realist error. They judge as if Maxi's belief accords with theirs.• Even when they agree Maxi didn’t see the Dad move the ball• Even when told Maxi doesn’t know the ball has moved.
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Implicit understanding:Clements & Perner (1994).
“I wonder where he’s going to look?” • Measure eye direction
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Eyes look to false location (correct) butchild subsequently points totrue location (incorrect).
Similar effect withspontaneous gesture vs reflective point -“Quick, catch him!”
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Possible interpretations (not mutually exclusive):
(i) looking studies over-estimate conceptual understanding; (ii) searching studies under-estimate;
(iii) different measures tap different types of knowledge representation
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(i) Looking studies over-estimate conceptual understanding
Bogartz (1997)Infants’ looking results can be interpreted in terms of perceptual processes.
• Infant makes comparisons between immediatePerceptual input and what is in associative memory.Looking time is related to degree of mismatch.
• Explains drawbridge results without assuming anyknowledge of occluded object.
• General strategy: don’t impute conceptual understanding unnecessarily.
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(ii) Searching studies under-estimate competence
e.g. Problems with executive control –Child has difficulty inhibiting prepotent responsein search tasks. True competence is masked.
• General strategy: check that ‘genuine’ understanding isnot masked by task demands.
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(iii) Measures tap different types of knowledge representation
• Strength of representationNeed ‘stronger’ representation for prediction than for recognizing violation of expectancy?
Keyong & Spelke (1999). 3-4 year olds view launching of object off cliff – judge impossible trajectories to look silly, but predict landing location vertically down.
• Implicit vs explicit representationE.g. Karmiloff-Smith (1992)Dienes & Perner (1999)
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Karmiloff-SmithProcess of re-representation:‘a specifically human way to gain knowledge is for the mind to exploit internally the information that it has already stored, by…. re-representing in different representational formats what its internal representations represent’
Examples – playing piano; drawing man with 2 heads.
Four levels – Implicit (behavioural mastery; knowledge not available
to the system); Explicit E1 (still not available to consciousness);E2/3 (explicit verbal report).
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Dienes & Perner (1999)What is represented:
Implicit: only content of knowledge represented: ‘cat’
(various levels in between)
Explicit: content + propositional attitude represented:‘I know this is a cat’
In both accounts, most explicit level of representationis ‘knowing that you know’.
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Donald Rumsfeld (2003)US defence secretary:
“…. There are known knowns; there are things we know we know.We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns – the ones we don’t knowwe don’t know.”
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Coming to know that you knowSummary and further questions:
1. We impute knowledge on the basis of output 2. Infants: Looking times imply knowledge not revealed by search3. Childhood: looking direction and spontaneous search implyknowledge not revealed by reflective response
4. The same knowledge can be represented in different ways,on dimension implicit to fully verbally explicit5. At implicit level, child simply knows6. At most explicit level, child knows that she knows
What are the disadvantages of simply knowing?What are the benefits and costs of knowing that you know?
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II. Coming to know how you know –Deliberate seeking of informative knowledge sources
Knowing that you don’t know – impetus to finding out?
• Direct vs indirect sources of knowledge
• Knowing what kind of knowledge we get from what source
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These look the same but feel different, one hard, one soft
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These feel the same but look different
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Child agrees the toys look the same but one hard, one soft
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One toy slipped into tunnelWhich one?
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Child decides whether to look or feel
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Child then has other mode of access.Finally child asked “Which one is it? How do you know….?”
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00.20.40.60.8
11.21.41.61.8
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Choice Source
3-4 yrs
4-5 yrs
adult
Choice: “Do you need to see or feel to find out if it’s the hard one or the soft one?”
Source: (having both seen and felt) “How do you know it’s the hard one?”
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3-4 yr olds poor at:• Predicting what knowledge they will get from looking or feeling.
• Reporting how they got to know.
• Standard interpretation of poor performance:3-4 yr olds do not understand connection between information access and knowledge state.
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Identifying precursors of explicit understanding:
1. Test explicit understanding of ‘simpler’ conceptse.g. epistemic vs non-epistemic access (Pillow, 1993)
• 3 yr olds judge its better to look inside a box than to stand on top, to find out what’s inside.
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2. Test ‘simpler’ representations of same concepts
•Experimenter places toy out of reach ‘Which one is it?’Does child say ‘hard one’ before feeling? NODoes child say ‘red one’ before feeling? YES
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0
0.5
1
1.5
2
2.5
3
3.5
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3-4 yrs Adult
Feel trial
See trial
Feel trial: toy hard or softSee trial: toy red or blue3-4 yr olds behave as if they know when seeing is uninformative
No. of timesChild feels toybefore sayingidentity
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Is 3-4 yr old more likely to believe what she’s told by a well-informed speaker than a poorly-informed speaker?YES
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One toy slipped into tunnelWhich one?
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Experimenter invites child to have a look. “Which one do you think it is?” “The soft one”
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Experimenter feels “I’ll say which one I think it is – the hard one”
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Identity judgment: “Which one is it?”Source judgment: “How do you know…..?”
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0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
Both guessing Experimenterinformed
3-4 yrs
Adult
3-4 yr olds behave as if they understand about information access,even though they perform poorly on tasks which demand explicitunderstanding.
Number of timeschild acceptsexperimenter’ssuggestion
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Coming to know how you knowSummary and further questions:
1. Knowing that you don’t know provides impetusfor active seeking of knowledge
2. Knowledge gained from direct and indirect sources3. 3-4 yr olds lack reflective, explicit knowledge of sources
of information4. But they behave as if they do understand
What are the disadvantages of having only working understanding about sources of knowledge?What are the benefits and costs of achieving reflectiveunderstanding?
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III. Coming to know what you know –Considering reality within a context of possibilities
1. Considering what actually happened in the context ofwhat could have happened insteadand what could happen in the future
2. Differentiating interpretations of reality from ‘reality’ itself
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Counterfactuals & Future Hypotheticals:
Counterfactuals Thinking about what might have been, but isn’t.
Typical developmental task: Jenny makes a painting and leaves it on the garden table. The wind blows the painting up into a tree.“What if the wind hadn’t blown? Where would the picture be?”
Riggs et al, 1998
4 years olds answer these questions correctly.
Future HypotheticalsSpeculating about a future event“What if next time…?”
Future: “What if next time he drives the other way, where will he be?”Counterfactual: “What if he had driven the other way, where would he be?”
3yr olds good at future hypotheticals.(Riggs et al, 1998; Robinson & Beck, 2000; Perner et al 2004)
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When 4 yr olds answer hypothetical and counterfactual questions correctly,are they really thinking about possibilities?
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The slide task
Cotton wool
Barriers
Future hypothetical: “What if next time he goes the other way?”Undetermined: “Can you put out cotton wool?”
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Future: “What if next time he goes the other way?”Undetermined: “Can you put out cotton wool?”
Future hypotheticals are easier than undetermined for both age groups
Similar pattern with counterfactuals vs undetermined
5-6 yr olds near ceilingon all tasksAGEGRP
4-5 yrs3-4 yrs
Me
an
2.0
1.5
1.0
.5
0.0
Undetermined
Future Hypothetical
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• 3-4 year olds can think about an event in the future
• 4-5 yr olds can think about an event which could havehappened in the past but didn’t
• 5-6 yr olds can represent two possible outcomes of a single event. Beginning of mental separation of ‘reality’ from ‘interpretations of reality’
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Coming to know what you knowSummary and further questions
1. 3 yr olds can think about events beyond the here and now2. 4 yr olds can think about an event that could have happened
but didn’t3. 5-6 yr olds can represent possible events and begin to differentiate interpretations of reality from reality itself
What are the disadvantages of being confined to the here and now?What are the benefits and costs of considering reality within aset of possible alternatives?What are the benefits and costs of differentiating reality frominterpretation?
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Summary and questions for the future
I. Coming to know that you know: problems of imputing knowledge on the basis of outputimplicit to explicit knowledgeknowing that you know - knowing that you don’t know
II. Coming to know how you know:direct and indirect sources of knowledgeknowing how to find outknowing how you got to knowimplicit to explicit knowledge
III. Coming to know what you know:differentiating reality from possibilitiesnecessarily explicit?
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Summary and questions for the future continued
How to differentiate ‘wrong’ metacognition from nometacognition?
How does system divide resources between cognition andmetacognition?
How do explicit representations feed back to implicit ones?How do explicit representations influence behaviour?
How does system learn about sources of knowledge,especially indirect sources?
