John Dewey
"[CT is an] active, persistent, and careful consideration of a belief or supposed form of knowledge in the light of the grounds which support it and the furthest conclusions to which it ends (Dewey, 1910, p. 6).”
John Dewey is credited with being the progenitor of many modern educational ideals, critical thinking being no exception. He states that reflective thinking, his homologue to critical thinking is an "active, persistent, and careful consideration of a belief or supposed form of knowledge in the light of the grounds which support it and the furthest conclusions to which it ends (1910, p. 6).” His definition acknowledges a few traits that will become hallmarks of later interpretations, most notably the active nature of critical thought which contrasts typical, everyday thought and his emphasis on reasons and implications.
John Dewey's 1910 book, How We Think, can be accessed online for free through Google Books.
John Dewey
Richard Paul
Robert Ennis
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Image: By Eva Watson-Schütze (1867-1935) [Public domain], via Wikimedia Commons