Intentional with a ‘t’ and Intensional with an ‘s’

These are two specialist philosophical terms which are used in similar contexts, which are pronounced identically, which are spelt the same way apart from one letter, and yet which mean totally different things! Confused? Don’t be!

Intentionality

‘Intentionality’ is the property of being about or being directed towards something else. Consciousness is always consciousness of something and thoughts, dreams etc are always about something. Therefore the mind has intentionality, and one of the puzzles about consciousness is to explain how this comes about.

Intensionality/Extensionality

‘Intension’ and ‘extension’ are concepts to do with the meaning of words or phrases. The extension of a term is the class of objects it describes (for example, the extension of ‘tiger’ is the class containing all the tigers in existence, and only these). The intension of the same predicate is the condition which objects must satisfy for it to pick them out. In the case of ‘tiger’, the intension might be ‘carniverous quadruped with black and orange stripes and a tail.’