A "concept" is logically uniquely identified and symbolized

Some people use the word "abstract" to refer to something created by collecting many concrete things and extracting a common form (elephant), while others use it simply to refer to something vague.

The latter use "abstract concept" or "concept" to mean "vague idea."

Eugene Gendlin, on the other hand, defined "concept" as in the title.

So this means that "something that is not vague" is a concept.

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