It has been suggested that a rigid definition for a category is not possible and that resemblance (much like a family resemblance) may be more appropriate. Why is this the case?

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Quizplus · Accepted Answer

Categorization is often a matter of degree, with some members being more typical of the category than others. This makes it difficult to establish a rigid definition for a category, as there may be exceptions and borderline cases. Additionally, categories are not fixed and can change over time as new members are added. Finally, judgments of similarity are often subjective and may depend on context and individual perspectives.

It Has Been Suggested That a Rigid Definition for a Category