Objects coordinated with concepts are distinguished by possession of the properties in terms of which the designating concepts are defined.

Schlick claimed the method of definition by axioms was implicit because, unlike explicit definition, occurrences of the defined term cannot necessarily be replaced by a combination of the expressions which define it. And he praised the method for its specification of meanings independently of any intuitive content. Implicitly defined terms possess a clarity and precision of scope which cannot be achieved by concepts defined by abstraction from experience. Since, of course, axiomatic definitions