Artificial intelligence, a new and exciting technology, is not a new concept in human imagination.  The idea can be found at least as far back as the pre-Christian Greeks and in all ages thereafter.  Homer was acquainted with the concept of AI, perhaps 800 years B.C., and the ancient historian Polybios believed that Nabis, a dictator of Sparta (about 200 B.C.), used a robot to compel rich but recalcitrant citizens to pay their taxes.  We tend to think that artificial intelligence is a new idea, hatched in the computer age.  In fact it is an ancient notion.

This next section describes some of the historical and imaginative background to modern AI.  Artificial intelligence, as a subclass of computer science, springs from the same soil.  The early history of computation, in fact and fiction, is a description also of the genesis of intelligent machines.

It is also necessary to say something about the objections to the idea of AI, the notion that artificial intelligence is somehow an affront to common sense and humanity.  It is sometimes even said that 'artificial intelligence' is a contradiction in terms, the corollary being that intelligence is a unique property of certain types of natural biological systems.  But this type of objection is being outflanked by the event.  Intelligent machines are already working amongst us.  This chapter gives some indication of what they are up to (to be explored in more detail later), and some idea of what we may expect in the future.  Any suggested predictions are not given dates, firm or tentative.  It is enough that machine competence is developing at a rapid rate.