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Summary: Critical Thinking

Critical thinking has been advo­cated as an educational goal since the 1950s. Psychologists, who are skeptical as a group, value critical thinking.

Science can be described as an attempt to create maps or models of natural systems. To gather scientific evidence, one must use operational definitions. Operational definitions relate the words of a claim to specific measurement operations.

Operational definitions must be known in order to accomplish replications of surprising findings. However, operational definitions are not automatically scientific or "good." They are subject to scrutiny and criticism like any other part of the scientific process.

Replication is critically important to science. Sometimes through an innocent error, or more rarely through fraud, incorrect results will find their way into the literature. These are detected and corrected through efforts at replicating surprising or important results.

The original researchers are naturally disappointed when a replication fails, but typically they will help to analyze the failure of replication and suggest ways to improve the testing procedures. If a result is truly incorrect, attempts at replication will produce smaller and smaller effects (if any) as experimental controls are tightened up.

The Quack Science syndrome is a set of distinctive traits that marks unscientific theories. Commonly these are the ideas of one individual who wants to pass them off on the public as a scientific breakthrough.

Quack science is typically publicized outside the scientific journal system. The scientific establishment is commonly accused of a conspiring against the new ideas.

Quack scientists may invest great energy in creating web sites, publishing books, and giving magazine and newspaper interviews. Notably absent from the repertoire of a quack scientist are publications in legitimate peer-reviewed journals or non-trivial predictions based on the new, revolutionary theory.

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