from the intentional stance we predict behaviour by treating the system as an intelligent agent with its own beliefs and desires. Dennett’s standard example is a chess-playing computer. It is not practical to treat a chess-playing computer from either the design or physical stances when playing against it – it is much more fruitful to treat it as if it had beliefs and desires, that is, from the intentional stance.

In Dennett’s usage, ‘a particular thing is an intentional system only in relation to the strategies of someone who is trying to explain and predict its behavior.’ (Dennett, 1978), p.4.