A collection of mental processes leading up to a decision on the
merit of a proposal or product, where ‘merit’ could
be in terms of truth, usefulness, effectiveness, significance, desirability,
and so on.
Components of Critical Thinking
- Prior knowledge,
- Access to meanings of words and sentences,
- A set of mental dispositions,
- A set of mental abilities, and
- A set of criteria of evaluation.
For instance, we reject the claim that humans have 15 fingers on
each hand on the basis of our prior knowledge of human beings. Many
of us may not have sufficient prior knowledge of horses to evaluate
the truth of the claim that horses have 24 teeth.
For instance, the claim that the majority of human beings have
four fingers on each hand is false if the intended meaning of the
word ‘finger’ is ‘any digit on the hand’,
but true if it is ‘any digit on the hand excluding the thumb’.
The same remark applies to the astronomer’s rejection of the
traditional claim that there are nine planets in the Solar system:
eliminating Pluto from the set of planets depends on the meaning
we ascribe to the word ‘planet’.
- Intellectual skepticism, i.e. not believing or rejecting anything
without carefully considering the evidence for and against it;
- Willingness to question and demand evidence;
- A sense of the uncertainty and fallibility of human knowledge;
- Openness of mind, i.e. readiness to reject elements of prior
‘knowledge’ on the basis of new evidence and thinking.
- Ability to identify (a) refuting information, (b) supporting
information, (c) internal logical contradictions, and (d) flaws
- Ability to reason, i.e. to make legitimate inferences.
- Ability to think of alternative interpretations.
Criteria of Evaluation
For instance, the criteria of evaluating theories in the physical
sciences include logical consistency, correctness of predictions,
simplicity, and generality. Engineering and technology may replace
simplicity with cost. Correctness of predictions is irrelevant for
Mohanan, K.P. (1997). ‘How Does Education
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Thinking in Science Education’. http://courses.nus.edu.sg/course/ellkpmoh/educ/NIE.rtf
Mohanan, K.P. ‘Modes of Justifying Knowledge
Pan, D. (1999). ‘Critical Thinking’.
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