 The AI researcher starts with an intentionally characterized problem (e.g., how can I get a computer to understand questions of English?), breaks it down into sub-problems that are also intentionally characterized (e.g., how do I get the computer to recognize questions, distinguish subjects from predicates, ignore irrelevant parsing?) and then breaks these problems down further until he reaches problem or task descriptions that are obviously mechanistic. (Dennett 1978: 80)