Final answer:
The claim that mental categories have fuzzy boundaries means that category membership is a matter of degree, not an all-or-nothing distinction. The boundaries for a general category are less clear-cut than the boundaries for a basic-level category. Different individuals may have somewhat different concepts, making it easy for people to disagree about how a particular object should be categorized.
Step-by-step explanation:
The claim that mental categories have fuzzy boundaries means that category membership is a matter of degree, not an all-or-nothing distinction. It implies that the boundaries for a general category are less clear-cut than the boundaries for a basic-level category. Different individuals may have somewhat different concepts, leading to disagreements in categorization.