The Critical Thinking Co.™
"Critical thinking is the identification and evaluation of evidence to guide decision making. A critical thinker uses broad in-depth analysis of evidence to make decisions and communicate his/her beliefs clearly and accurately."

Other Definitions of Critical Thinking:

Robert H. Ennis, Author of The Cornell Critical Thinking Tests
"Critical thinking is reasonable, reflective thinking that is focused on deciding what to believe and do."

A SUPER-STREAMLINED CONCEPTION OF CRITICAL THINKING
Robert H. Ennis, 6/20/02

Assuming that critical thinking is reasonable reflective thinking focused on deciding what to believe or do, a critical thinker:

1. Is open-minded and mindful of alternatives
2. Tries to be well-informed
3. Judges well the credibility of sources
4. Identifies conclusions, reasons, and assumptions
5. Judges well the quality of an argument, including the acceptability of its reasons, assumptions, and evidence
6. Can well develop and defend a reasonable position
7. Asks appropriate clarifying questions
8. Formulates plausible hypotheses; plans experiments well
9. Defines terms in a way appropriate for the context
10. Draws conclusions when warranted, but with caution
11. Integrates all items in this list when deciding what to believe or do

Critical Thinkers are disposed to:

1. Care that their beliefs be true, and that their decisions be justified; that is, care to "get it right" to the extent possible. This includes the dispositions to

a. Seek alternative hypotheses, explanations, conclusions, plans, sources, etc., and be open to them
b. Endorse a position to the extent that, but only to the extent that, it is justified by the information that is available
c. Be well informed
d. Consider seriously other points of view than their own

2. Care to present a position honestly and clearly, theirs as well as others'. This includes the dispositions to

a. Be clear about the intended meaning of what is said, written, or otherwise communicated, seeking as much precision as the situation requires
b. Determine, and maintain focus on, the conclusion or question
c. Seek and offer reasons
d. Take into account the total situation
e. Be reflectively aware of their own basic beliefs

3. Care about the dignity and worth of every person (a correlative disposition). This includes the dispositions to

a. Discover and listen to others' view and reasons
b. Avoid intimidating or confusing others with their critical thinking prowess, taking into account others' feelings and level of understanding
c. Be concerned about others' welfare

Critical Thinking Abilities:

Ideal critical thinkers have the ability to
(The first three items involve elementary clarification.)

1. Focus on a question

a. Identify or formulate a question
b. Identify or formulate criteria for judging possible answers
c. Keep the situation in mind

2. Analyze arguments

a. Identify conclusions
b. Identify stated reasons
c. Identify unstated reasons
d. Identify and handle irrelevance
e. See the structure of an argument
f. Summarize

3. Ask and answer questions of clarification and/or challenge, such as,

a. Why?
b. What is your main point?
c. What do you mean by…?
d. What would be an example?
e. What would not be an example (though close to being one)?
f. How does that apply to this case (describe a case, which might well appear to be a counter example)?
g. What difference does it make?
h. What are the facts?
i. Is this what you are saying: ____________?
j. Would you say some more about that?

(The next two involve the basis for the decision.)

4. Judge the credibility of a source. Major criteria (but not necessary conditions):

a. Expertise
b. Lack of conflict of interest
c. Agreement among sources
d. Reputation
e. Use of established procedures
f. Known risk to reputation
g. Ability to give reasons
h. Careful habits

5. Observe, and judge observation reports. Major criteria (but not necessary conditions, except for the first):

a. Minimal inferring involved
b. Short time interval between observation and report
c. Report by the observer, rather than someone else (that is, the report is not hearsay)
d. Provision of records.
e. Corroboration
f. Possibility of corroboration
g. Good access
h. Competent employment of technology, if technology is useful
i. Satisfaction by observer (and reporter, if a different person) of the credibility criteria in Ability # 4 above.

(The next three involve inference.)

6. Deduce, and judge deduction

a. Class logic
b. Conditional logic
c. Interpretation of logical terminology in statements, including
(1) Negation and double negation
(2) Necessary and sufficient condition language
(3) Such words as "only", "if and only if", "or", "some", "unless", "not both".

7. Induce, and judge induction

a. To generalizations. Broad considerations:
(1) Typicality of data, including sampling where appropriate
(2) Breadth of coverage
(3) Acceptability of evidence
b. To explanatory conclusions (including hypotheses)
(1) Major types of explanatory conclusions and hypotheses:
 (a) Causal claims
 (b) Claims about the beliefs and attitudes of people
 (c) Interpretation of authors’ intended meanings
 (d) Historical claims that certain things happened (including criminal accusations)
 (e) Reported definitions
 (f) Claims that some proposition is an unstated reason that the person actually used
(2) Characteristic investigative activities
 (a) Designing experiments, including planning to control variables
 (b) Seeking evidence and counter-evidence
 (c) Seeking other possible explanations
(3) Criteria, the first five being essential, the sixth being desirable
 (a) The proposed conclusion would explain the evidence
 (b) The proposed conclusion is consistent with all known facts
 (c) Competitive alternative explanations are inconsistent with facts
 (d) The evidence on which the hypothesis depends is acceptable.
 (e) A legitimate effort should have been made to uncover counter-evidence
 (f) The proposed conclusion seems plausible

8. Make and judge value judgments: Important factors:

a. Background facts
b. Consequences of accepting or rejecting the judgment
c. Prima facie application of acceptable principles
d. Alternatives
e. Balancing, weighing, deciding

(The next two abilities involve advanced clarification.)

9. Define terms and judge definitions. Three dimensions are form, strategy, and content.

a. Form. Some useful forms are:
(1) Synonym
(2) Classification
(3) Range
(4) Equivalent expression
(5) Operational
(6) Example and non-example
b. Definitional strategy
(1) Acts
 (a) Report a meaning
 (b) Stipulate a meaning
 (c) Express a position on an issue (including "programmatic" and "persuasive" definitions)
(2) Identifying and handling equivocation
c. Content of the definition

10. Attribute unstated assumptions (an ability that belongs under both clarification and, in a way, inference)

(The next two abilities involve supposition and integration.)

11. Consider and reason from premises, reasons, assumptions, positions, and other propositions with which they disagree or about which they are in doubt -- without letting the disagreement or doubt interfere with their thinking ("suppositional thinking")

12. Integrate the other abilities and dispositions in making and defending a decision

(The first twelve abilities are constitutive abilities. The next three are auxiliary critical thinking abilities: Having them, though very helpful in various ways, is not constitutive of being a critical thinker.)

13. Proceed in an orderly manner appropriate to the situation. For example:

a. Follow problem solving steps
b. Monitor one's own thinking (that is, engage in metacognition)
c. Employ a reasonable critical thinking checklist

14. Be sensitive to the feelings, level of knowledge, and degree of sophistication of others

15. Employ appropriate rhetorical strategies in discussion and presentation (orally and in writing), including employing and reacting to "fallacy" labels in an appropriate manner.

Examples of fallacy labels are "circularity," "bandwagon," "post hoc," "equivocation," "non sequitur," and "straw person."

Dewey, John
Critical thinking is "active, persistent, and careful consideration of any belief or supposed form of knowledge in the light of the grounds that support it and the further conclusions to which it tends (Dewey 1933: 118)."

Glaser
(1) an attitude of being disposed to consider in a thoughtful way the problems and subjects that come within the range of one's experiences, (2) knowledge of the methods of logical inquiry and reasoning, and (3) some skill in applying those methods. Critical thinking calls for a persistent effort to examine any belief or supposed form of knowledge in the light of the evidence that supports it and the further conclusions to which it tends. (Glaser 1941, pp. 5-6).

Abilities include: "(a) to recognize problems, (b) to find workable means for meeting those problems, (c) to gather and marshal pertinent information, (d) to recognize unstated assumptions and values, (e) to comprehend and use language with accuracy, clarity and discrimination, (f) to interpret data, (g) to appraise evidence and evaluate statements, (h) to recognize the existence of logical relationships between propositions, (i) to draw warranted conclusions and generalizations, (j) to put to test the generalizations and conclusions at which one arrives, (k) to reconstruct one's patterns of beliefs on the basis of wider experience; and (l) to render accurate judgments about specific things and qualities in everyday life." (p.6)

MCC General Education Initiatives
"Critical thinking includes the ability to respond to material by distinguishing between facts and opinions or personal feelings, judgments and inferences, inductive and deductive arguments, and the objective and subjective. It also includes the ability to generate questions, construct, and recognize the structure of arguments, and adequately support arguments; define, analyze, and devise solutions for problems and issues; sort, organize, classify, correlate, and analyze materials and data; integrate information and see relationships; evaluate information, materials, and data by drawing inferences, arriving at reasonable and informed conclusions, applying understanding and knowledge to new and different problems, developing rational and reasonable interpretations, suspending beliefs and remaining open to new information, methods, cultural systems, values and beliefs and by assimilating information."

Nickerson, Perkins and Smith (1985)
"The ability to judge the plausibility of specific assertions, to weigh evidence, to assess the logical soundness of inferences, to construct counter-arguments and alternative hypotheses."

Moore and Parker, Critical Thinking
Critical Thinking is "the careful, deliberate determination of whether we should accept, reject, or suspend judgment about a claim, and the degree of confidence with which we accept or reject it."

Delphi Report
"We understand critical thinking to be purposeful, self-regulatory judgment which results in interpretation, analysis, evaluation, and inference, as well as explanation of the evidential, conceptual, methodological, criteriological, or contextual considerations upon which that judgment is based. CT is essential as a tool of inquiry. As such, CT is a liberating force in education and a powerful resource in one's personal and civic life. While not synonymous with good thinking, CT is a pervasive and self-rectifying human phenomenon. The ideal critical thinker is habitually inquisitive, well-informed, trustful of reason, open-minded, flexible, fair-minded in evaluation, honest in facing personal biases, prudent in making judgments, willing to reconsider, clear about issues, orderly in complex matters, diligent in seeking relevant information, reasonable in the selection of criteria, focused in inquiry, and persistent in seeking results which are as precise as the subject and the circumstances of inquiry permit. Thus, educating good critical thinkers means working toward this ideal. It combines developing CT skills with nurturing those dispositions which consistently yield useful insights and which are the basis of a rational and democratic society."

A little reformatting helps make this definition more comprehensible:

We understand critical thinking to be purposeful, self-regulatory judgment which results in

•          interpretation
•          analysis
•          evaluation
•          inference

as well as explanation of the

•          evidential
•          conceptual
•          methodological
•          criteriological
•          contextual

considerations upon which that judgment is based.

Francis Bacon (1605)
"For myself, I found that I was fitted for nothing so well as for the study of Truth; as having a mind nimble and versatile enough to catch the resemblances of things … and at the same time steady enough to fix and distinguish their subtler differences; as being gifted by nature with desire to seek, patience to doubt, fondness to meditate, slowness to assert, readiness to consider, carefulness to dispose and set in order; and as being a man that neither affects what is new nor admires what is old, and that hates every kind of imposture."

A shorter version is "the art of being right."

Or, more prosaically: critical thinking is "the skillful application of a repertoire of validated general techniques for deciding the level of confidence you should have in a proposition in the light of the available evidence."   

HELPFUL REFERENCE:
http://plato.stanford.edu/entries/logic-informal/