|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.|
Books on Amazon
Extension/truth regarding the extension superassertibility can potentially diverge from the actual assertibility - e.g. gold at the time of Aristotle.
Wahrheit und Objektivität Frankfurt 2001