|Extension, philosophy: an object, for example, the planet Venus as a material body, independent from the manner in which it is singled out. In contrast, intension is the way in which the object is given or is represented, e.g. Morning star or Evening star. See also intensions, identity, identity conditions, reference, meaning, assertibility conditions, propositional attitudes, opacity.|
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E.g. "piglet" can have different extensions.
Expressive Vernunft Frankfurt 2000
Begründen und Begreifen Frankfurt 2001