Transcript Can We Really Think Critically Let Alone Teach It?

Critical Thinking:
The Biological Basis of How We Do
It, Learn It, and Teach It
Peter L. Walton, M.D.
Associate Dean for Academic Affairs
School of Public Health and Information Sciences
iClicker Question 0 (15 sec.)
“Critical thinking is a cognitive activity that:
• can be learned,
• is difficult to teach or evaluate,
• requires an organized and rational
approach,
• and to succeed must become a nearly
automatic function.”
A. True
B. False
Agenda
Declarations
Central Question and F&PCs
Warm-up
… and we’re off …
– Others’ thoughts on critical thinking
– Exercises for you to feel less certain about:
• Your senses
• Your cognition
• Your objectivity
Groundwork
– Natural selection
– Genetics, et al.
– Neuroscience
Individual vs. team sport
Teachers vs. students
Conclusions
Suggestions
WARNING: All of this is
46% of the slides, doesn’t
mention critical thinking
at all, but is indispensible
for making any sense of
the rest.
• My goal is awareness, not
understanding or agreement.
• I’ll be covering lots of dots
quickly, often without
connecting them.
• These are left for you to do at
your leisure.
Declarations
I’m an unabashed and unrepentant i2a groupie (redundantly speaking).
I’m all for critical thinking but accept that it too is subject to critical thinking.
Everything in my presentation is based on currently accepted evidence.
– However, a lot of what I’ll say, while based on evidence, is still conjectural and in
italics.
I currently accept the following as fundamental for critical thinking:
–
–
–
–
–
Critical thinking is an instance of the scientific method, which includes emotion.
Whether free will exists or not is a distracter. Ditto for consciousness.
Biases/heuristics are both good and bad for critical thinking.
Certainty is a emotion.
Most approaches to critical thinking (e.g., Paul-Elder) are based on a classification
system.
– All classification systems are falsifiable (see Gödel) but many are extremely useful.
– My biases lead me to accept and communicate these fundamentals.
– Some or all of these fundamentals are likely in error.
iClicker Question 1 (15 sec.)
With which of the following of my declarations are you the MOST
UNCOMFORTABLE?
A. Critical thinking is an instance of the scientific method, which
includes emotion.
B. Certainty is a emotion.
C. Most approaches to critical thinking (e.g., Paul-Elder) are
based on a classification system.
D. All classification systems are falsifiable (see Gödel) but many
are extremely useful.
E. Other.
No response = None
Central Question
"Can we really think critically let alone teach it?"
Fundamental & Powerful Concepts
•
•
•
•
•
Natural selection
Sexual reproduction
Intuition/emotion
Bias/heuristic
Socialization
Any questions?
Quick Peek at the End of the Book
Can we really think critically?
Yes. But not the way we think we do.
Let alone teach it?
Yes. But not the way we think we are.
Agenda
Declarations
Central Question and F&PCs
Warm-up
– Others’ thoughts on critical thinking
– Exercises for you to feel less certain about:
• Your senses
• Your cognition
• Your objectivity
Groundwork
– Natural selection
– Genetics, et al.
– Neuroscience
Individual vs. team sport
Teachers vs. students
Conclusions
Suggestions
Fun
part
Others’ Thoughts on Critical Thinking
“The human understanding supposes a greater degree of order…in things
than it really finds.”
-- Francis Bacon, Novum Organum, 1620
“Truth will sooner come out of error than from confusion.”
-- Francis Bacon, ?1623
“Our whole problem is to make mistakes as fast possible.”
-- John Wheeler, presumably updating Francis Bacon
“The real purpose of [critical thinking] is to make sure Nature hasn’t misled
you into thinking you know something that you actually don’t.”
-- Robert Pirsig, Zen and Art of Motorcycle Maintenance, 1974
“The first principle is that you must not fool yourself -- and you are the
easiest person to fool.”
-- Richard Feynman, 1974
“The greatest obstacle to discovery is not ignorance -- it is the illusion of
knowledge.”
-- Daniel Boorstin, Librarian of Congress, 1984
iClicker Question 2 (10 sec.)
The BLUE line CD on the right is what percent as
long as the RED line AB on the left?
A. 60%
B. 70%
C. 80%
D. 90%
E. 100%
The BLUE line CD on the right is what percent as
long as the RED line AB on the left?
E. 100%
iClicker Question 4 (15 sec.)
• I toss two coins, promising that if at least one
of them comes up heads, I will tell you.
• I look at both coins and volunteer that at least
one is indeed a head.
What’s the chance that the other is also a
head?
A. 25%
C. 50%
E. 75%
B. 33%
D. 66%
Two Coins But No Fountain
• I toss two coins, promising that if at least one of
them comes up heads, I will tell you.
• I look at both coins and volunteer that at least
one is indeed a head.
There are four possible cases: HH, HT, TH, TT.
Three of these have at least one head: HH, HT, TH
Of those three, one has a second head: HH
The chance of the other being a head is 33% (answer B).
iClicker Question 6 (30 sec.)
Which of these cards must you turn over to
determine whether this rule is true or not:
“If there is a vowel on one side, there is an
even number on the other side”?
A
A. A only
B. 2 only
K
2
C. A and 2
D. A and 7
7
E. other
A Card Game
Rule” “If there is a vowel on one side, there is an even number
on the other side.”
You must turn over the “A” card to see if there’s an even
number on the other side (verification)
and the “7” card to see if there’s a vowel on the other side
(falsification).
The other cards are of no use.
A
K
Answer: D. A and 7
2
7
Everybody turns over “A”; 4% turn over “7”, while the rest
either are done or turn over the “2” (confirmation bias).
Agenda
Declarations
Central Question and F&PCs
Warm-up
– Others’ thoughts on critical thinking
– Exercises for you to feel less certain about:
• Your senses
• Your cognition
• Your objectivity
Groundwork
– Natural selection
– Genetics, et al.
– Neuroscience
Individual vs. team sport
Teachers vs. students
Conclusions
Suggestions
Challenging
part
Natural Selection
A very brief synopsis of natural selection:
– Natural selection is not blind – it simply has no intent or
purpose.
– The outcome of natural selection is selective persistence –
nothing else.
– Persistence requires replication, which requires replicators to
have fidelity, fecundity, and longevity – nothing else.
– Lineages that tend to persist tend to persist.
– Characteristics that enhance lineage persistence tend to persist
with their lineages.
And intuition is one of these characteristics.
Intuition
Cognitive scientists have found that most (>99%)
of our day-to-day “decisions” make essentially sole
use of our ability to “think” without awareness.
This is intuition.
Our use of intuition does not decrease much when
what we are deciding is important (e.g., life and
death) or unimportant (e.g., what to wear).
In fact, the use of intuition increases as expertise
in an area increases.
And biases are essential agents in intuition.
Biases
A vital persistence characteristic in natural selection is
the ability to act quickly.
Simple heuristics evolved to support acting quickly.
These heuristics are biases.
Some are deemed “good” by humans, e.g.:
– Type 1 vs. type 2 errors
– Certainty
Some are deemed “bad” by humans, e.g.:
– Framing
– Confirmation
And all of them evolved by enhancing persistence.
A Really Major Characteristic
Sexual reproduction:
– Enhances persistence in presence of parasites
– Enhances diversity within lineages
Consequences:
– Socialization:
• Group identity (e.g., tribalism, both by blood and mating and,
in humans, by acquired characteristics, e.g., golf playing)
• Specialization
• Specialty selection by distinctions of traits and/or lineages
• Differential and non-linear valuations of specialties
– Sexual selection:
• Handicap principle
And everything is governed by genetics (sort of).
Genetics, et al.
DNA
–Everything life is capable of is dictated by DNA –
but with important additional considerations.
Genes – about 2-3% of DNA
–Encoded for structural and worker molecules –
protein.
RNA – uncertain % but probably all the rest
–Encoded for controlling production of proteins and
RNA and for controlling the control of RNA
There is no “junk” in DNA.
More Genetics, et al.
Epigenes
– RNA that controls DNA and its expression and controls
RNA in response to the environment
Nature vs. nurture
– There is no “vs.” – they cooperate, more or less
– DNA (nature) enables the environment (nurture) to
modify the expression of DNA (nature) to adapt to the
environment (nurture). Repeat until dead.
And neuroscience is learning how genetics, et al.
provide mechanisms for persistence of intuition,
cognition, and decision making.
iClicker Question 8 (15 sec.)
Between birth and sexual maturity, which of
the following happens to our brain’s neurons,
on average?
A. We double the number of neurons.
B. We increase the number of neurons by 23%.
C. We keep the same number of neurons.
D. We decrease the number of neurons by 12%.
E. We halve the number of neurons.
Neuroscience
Neuron pruning
– Between birth and sexual maturity, we “prune” (i.e.,
kill) 50% of the neurons we’re born with.
– This is in response to our environment (adaptation).
– Post-pruning we add and prune neurons throughout
our lives to a much lesser extent.
Synapse pruning
– We add and prune connections among neurons in
adapting to our environment, primarily during initial
neuron pruning.
– Post-pruning we add and prune synapses throughout
our lives, again to a much lesser extent.
Neuroscience
Glial cells
– Outnumber neurons by ~9:1.
– Initially thought to only provide
structural support for neurons.
– Recently found to also “nurture”
neurons – blood supply, nutrients, and
connection speed.
• Each neuron has many caretaker glial
cells.
• Each glial cell may be caretaker to several
neurons.
– Likely responsible for both neuron and
synapse pruning.
More Neuroscience
Mirror neurons
– Appear to be involved in understanding the actions of
others (by simulation and empathy) and learning new
skills (by imitation).
– Located in many parts of the brain.
Prefrontal cortex
– Primary location for integration of emotion, intuition,
and cognition.
– Essential for decision making.
– Matures at differing stages and rates by gender and
individual.
Token Picture and Quote
Prefrontal
cortex
“Depending on their target of influence, representations in the PFC can function
variously as attentional templates, rules, or goals by providing top-down bias signals to
other parts of the brain that guide the flow of activity along the pathways needed to
perform a task.” Miller EK, Cohen JD (2001). "An integrative theory of prefrontal cortex function". Annu Rev Neurosci 24: 167–202.
Even More Neuroscience
Experiment: Motor action by intention
– Finding: Sequence is not decide-prepare-act but rather
prepare-decide-act.
– Finding: Deciding follows preparing by about 0.4
second.
Experiment: Timing of action and awareness of
action
– Finding: Awareness follows action by about 0.4
second.
Experiment: Neuron behavior in binary-bet game.
– Finding: Neuron activity indicated bet decision on
average 2.8 seconds before subjects “decided” on bet.
Still More Neuroscience
Experiment: Differentially rewarded and penalized
multi-card deck game (Iowa Gambling Task):
– Finding: Most subjects identify “good” and “bad” decks
after 40-50 card flips.
– Finding: Subjects show stress responses to “bad” decks
after about 10 card flips.
– Finding: Younger college subjects perform worse than
older ones (?immature prefrontal cortex).
– Finding: College education is predictor of poorer
performance (?emphasis on rational thought vs.
emotion).
One More from Neuroscience
Subjects: Individuals whose prefrontal cortex has
been damaged such that integration of
emotion is decreased or absent.
Finding: Unable to make everyday decisions (e.g.,
Coke or Pepsi) and life-altering decisions (e.g.,
change jobs).
Conclusion: Emotion is essential for decisionmaking.
Theory: Immediate gratification trumps long-term
gratification even knowing the potential
negative results of the former in the long run.
Agenda
Declarations
Central Question and F&PCs
Warm-up
– Others’ thoughts on critical thinking
– Exercises for you to feel less certain about:
• Your senses
• Your cognition
• Your objectivity
Groundwork
– Natural selection
– Genetics, et al.
– Neuroscience
Individual vs. team sport
Teachers vs. students
Conclusions
Suggestions
Frustrating
part
iClicker Question 9 (10 sec.)
Critical thinking is:
A. An individual sport.
B. A team sport.
C. Both.
D. An illusion.
E. I have no idea.
Individual vs. Team Sport, Round 1
A brief recap:
Natural selection
Lineage persistence
Sexual reproduction
Conclusion:
– Our brains evolved for
socialization
– and for selection
– and selection is a dynamic mix
of competition, cooperation,
and collaboration.
Socialization
Sexual selection
Specialization
Specialty selection
Brain functions
Genetics, et al.
Individual vs. Team Sport, Round 2
A single person doing science in isolation could be
doing science or could be fooling herself and doing
anecdotes.
– Note: The plural of anecdote is not data.
A good way for her not fool herself is to for others
do the same things and see if they get the same
results. A.k.a. the scientific method.
The same must hold for critical thinking since it’s
an instance of the scientific method.
So critical thinking is a team sport!
Individual vs. Team Sport, Round 3
Hold on there, You. I think critically – I put together this
presentation after all!
True. Specialty selection does not result in everyone in the
specialty having the same level of performance in the
specialty.
Many scientists frequently have their findings confirmed.
So critical thinking is an individual sport to an extent that
varies among critical thinkers.
And the way a critical thinker determines his own extent is by
sharing his thinking with other critical thinkers to see what
they think about it. He also learns about others’ thinking
(?partly via mirror neurons).
Individual vs. Team Sport, Round 4
So critical thinking is an individual sport up to a
point
that varies by individual and within an individual
by ability and practice,
that requires critical thinking to be a team sport
for practicing,
and that ultimately is a team sport determining
the extent to which an individual can play
individually and still be part of the team.
Teachers vs. Students
Item
Teacher (modal)
Student (modal)
Intuition
well-trained, stable
in training, unstable
Inventory of biases
large, organized, integrated, slowly
changing
small, unorganized, poorly
connected, rapidly growing
Sexual selection
established
in development
Inventory of handicaps
established
in development
Replication
yes
no
Socialization
established
in development
Specialty selection
established, stable
in development, unstable
Prefrontal cortex
mature
immature, esp. in males
Critical thinking credential
Ph.D.
high school diploma
Critical thinking team
member of established team(s)
Unaware of concept or need
Critical thinking practice
10 years or more
3-4 years at most, mostly social
Critical thinking arena
academe, academic discipline
high school, socialization
Score: Teachers 12, Students 0
But there’s more …
Item
Teacher (modal)
Student (modal)
Percent who will be teachers
100%
<10% (increases at graduate level)
Individual critical thinking
advanced level, aware of level
beginning level, unaware of levels
Expectations of other role
self-initiated intellectual interest
and activity
self-initiated acceptance, guidance,
mentoring
Experience in other role
hindsight bias, self-serving bias
none
Mirror neuron contribution
“students aren’t that interested in
MY
my course”
course”
“teachers are just like my
MY parents”
parents”
Emotional contribution
“I’M not
“i’m
not as
as good
good aa teacher
teacher as
as iI
think I am”
“I’M not
“i’m
not as
as good
good aa student
student as
as iIused
usedto
to
be”
Cognitive contribution
“students aren’t as prepared as Ii
want them to be and Ii am”
“teachers aren’t that interested in ME”
me”
… and the bottom line …
Prefrontal cortex decision
business as usual
business as usual
Conclusions
Can we really think critically?
– Yes, but learning how took lots of time and practice in
an environment that nurtured implicit teamwork.
– And it still requires continual practice.
Let alone teach it?
– Yes, but we need to build in lots of time and practice in
an environment that provides explicit teamwork.
– And we need to balance what we love (content) with
what we use (critical thinking).
iClicker Question 10 (10 sec.)
Critical thinking is:
A. An individual sport.
B. A team sport.
C. Both.
D. An illusion.
E. I have no idea.
Suggestions
Here are some suggestions based on what we know
about natural selection, genetics, and neuroscience:
– Discuss the above and the teacher vs. student dilemma.
– Hold impromptu class discussions about course issues.
– Balance content and technique .
• Depth with critical thinking vs. breadth with factual recall.
– Evaluate deliverables using intellectual standards.
• Start with a few then add more as students catch on.
– Use a repeated exercise that has different content but
the same format, intent, and evaluation standards.
• Practice, practice, practice!
Suggestions (cont.)
– Include an analytic report using the elements of
thought (adapted) that is revised until it meets defined
evaluation expectations.
• Make achievement the constant and time the variable.
– Do group activities.
• T-P-S, peer evaluations, presentations
– Schedule office hours with groups of five students.
• Discuss course, philosophy, life, current events, whatever.
– Show and discuss a relevant movie or documentary.
– Implement team learning.
• But only if you’re committed to making it work.
Final Thoughts
Active learning simply means keeping students
cognitively active.
– This requires them to be under a mild but
perceptible level of stress.
– Expect it and nurture it.
– Tell students about it early on (e.g., class 1).
Essential aspects of learning and rationality are
intuition and emotion.
– Don’t avoid them. Enjoy using them.
– Tell students about them early on (e.g., class 1).
iClicker Question 12 (15 sec.)
“Critical thinking is a cognitive activity that:
• can be learned,
• is difficult to teach or evaluate,
• requires an organized and rational
approach,
• and to succeed must become a nearly
automatic function.”
A. True
B. False
Questions? Answers?
So long . . .
and thanks for all the fish.