© 2016 by Pearson Education, Inc.
Chapter 19
Critical Thinking in the Natural
Sciences
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Learning Outcomes
• Identify the kinds of questions natural
scientists ask
• Illustrate how natural scientists consider
intriguing phenomena, testable
explanation, experimentation, and
integration of findings
• Describe the investigative methods used
in the natural sciences
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Learning Outcomes
• Explain the standards used to evaluate
natural science research
• Describe social science applications in
fields such as climatology, medicine,
engineering, and agriculture
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Chapter Opening Video
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Critical Thinking Questions of
Natural Scientists
• Natural science: Systematic empirical
inquiry into the causal explanations from
the subatomic to the galactic in scope for
– Observed patterns
– Structures
– Functions of natural phenomena
• Thinking like a natural scientist
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Thinking Like a Natural Scientist
• Natural scientists:
– Ask questions about nature and natural
phenomena
– Investigate the empirically asked questions
– Utilize a shared understanding of terminology
and methods of inquiry
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Thinking Process of Natural
Scientists
• Think curious and intriguing natural
phenomenon
• Think empirically testable causal
explanation
• Null hypothesis
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Thinking Process of Natural
Scientists
• Think how to prevent and bring about the
phenomenon
• Think how to integrate new knowledge
with broader scientific understandings
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Think Curious and Intriguing Natural
Phenomenon
• Observations of scientists are related to
professional interests and training
• Natural phenomena that scientists find
intriguing are associated with team’s
project and program
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Think Empirically Testable Causal
Explanation
• Natural science requires explanations of
empirical reasoning applied to:
– Potentially testable hypothesis about causal
factors that produce the phenomenon
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Null Hypothesis
• Two events, factors, or phenomena are
not related
• Help investigators maintain a valuable
level of objectivity in work
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Think How to Prevent and Bring
About the Phenomenon
• Natural scientists prefer to mirror
experimentally a logical scenario
– If A, then B but not B so surely not A
• Thinking like a natural scientist implies:
– Discarding theories and explanations that are
not consistent with the experimental data
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Discussion Questions
• People with severe headaches often
experience physical reactions that hamper
their daily activities
– Has this happened to you?
• What physical reactions did you experience?
– Suppose you are a natural scientist, what
possibilities might you investigate for
preventing severe headaches?
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Think How to Integrate New Knowledge
With Broader Scientific Understandings
• Fundamental assumptions of natural
science
– Physical phenomena occur through
empirically discoverable causal mechanisms
– Physical universe is an integrated whole
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Think How to Integrate New Knowledge
With Broader Scientific Understandings
• Synthesizing knowledge
• Anomalies: Solid scientific findings that
are not consistent with prevailing theories
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Natural Scientists’ Investigation
• Testable hypothesis: Can be shown to
be false by reference to empirical
evidence
• Let the empirical question drive the inquiry
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Steps in a Scientific Investigation
• Identify a problem of significance
• Form a hypothesis
• Review the scientific literature to learn
from the work of others
• Identify all the factors related to the
hypothesis
• Make each factor measurable
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Steps in a Scientific Investigation
• Ensure that the experimental conditions
can be met
• Design a procedure to ensure the data
reveals the full range of observations
• Run a pilot to test the feasibility of design
plan
• Conduct the study/experiment and gather
the data
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Steps in a Scientific Investigation
• Conduct appropriate analyses of data
• Interpret the findings and discuss its
significance
• Critique the findings
• Publish the research
• Design a follow up study
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Let the Empirical Question Drive the
Inquiry
• Scientists do not retreat from an empirical
question
• Natural scientists treat a phenomena as a
falsifiable hypothesis and investigate it
empirically
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Let the Empirical Question Drive the
Inquiry
• Scientists are focused on scientific
interpretation and falsifiable question
• Empirical investigation of a hypothesis
requires documented data
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
How do Natural Scientists Think
About Standards?
• Confidence in scientific findings
• Confidence in scientific theories
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Confidence in Scientific Findings
• Strong critical thinkers assert findings with
warranted confidence
• True to a scientific certainty
– Causal factors in natural sciences function
with precision and regularity
– Statistical significance: Represents the
probability that an obtained result has not
occurred by chance
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Confidence in Scientific Findings
• Finding what isn’t there and not finding
what is there
– Wrong to conclude that reliance on numerical
data will eliminate human vulnerabilities
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Confidence in Scientific Theories
• Scientific research is iterative
• Understanding of natural phenomena
becomes accurate, and deeper with every
investigation
• Natural scientists embrace a set of
standards for evaluating scientific theories
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Confidence in Scientific Theories
• Explanatory scientific theories strive to be:
– Consistent
– Testable
– Comprehensive
– Productive
– Parsimonious
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Natural Science Applications in the
Real World
• Mitigation of the impact of global climate
change on human food supplies
• Microbiology, chemistry, and the promise
of gene therapy
• Interaction of genetics, environment, and
personal determination in lives
• Enviropig project and genetically modified
foods
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Natural Science Applications in the
Real World
• Science Education for New Civic
Engagements and Responsibilities
(SENCER)
– Sponsored by National Science Foundation
– Assists colleges and universities in the
development of science courses
– Focuses on real-world problems
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.
Sketchnote Video
THINK CRITICALLY, FACIONE
& GITTENS
© 2016 by Pearson Education, Inc.