Class (philosophy)

A class is a collection whose members either fall under a predicate or are classified by a rule. Hence, while a set can be extensionally defined only by its elements, a class has also an intensional dimension that unite its members. When the term 'class' is applied such that it includes those sets elements of which are intended to be collected without a common predicate or rule, the distinction can be indicated by calling such sets "improper class."

Class (philosophy)

A class is a collection whose members either fall under a predicate or are classified by a rule. Hence, while a set can be extensionally defined only by its elements, a class has also an intensional dimension that unite its members. When the term 'class' is applied such that it includes those sets elements of which are intended to be collected without a common predicate or rule, the distinction can be indicated by calling such sets "improper class."