Are humans machines? Can machines be like humans?
Such questions were posed first several centuries ago, when thinkers like Descartes and La Mettrie were faced with mechanical clocks and other devices which seemed-on their face-to do things which were, formerly, only within the domain of humans.1
To the first question, Hobbes and others began, in the 17th century, to use mechanical metaphors for thinking and intelligence. As well, the exploration and explanation of the body-as-machine, the mechanistic approach, emerged as paradigmatic; ancient puzzles such as the circulation of the blood, were solved. Anatomy and physiology, at least, used the model of the body-mechanic, to tell us a great deal about the nature of being human.
Currently, the quick retort to the first question-are humans machines-is “yes” and “no.” The essential human, the “anima” of Aristotle, the “soul” or “spirit” of many others, is being pushed about by tissue transplants (even across species in the case of baboon heart being implanted in a human infant), and by such techniques as artificial insemination. In the context of the kinds of dualism which have characterized Western thought, the body-mechanic had been given short shift. Now, it has raised serious questions of human and personal identity in our thinking. The importance and impact of the question has moved from the distant and the theoretical to the immediate and personal. Who anyone is (Who I am), is no longer as clear as it seemed to be, not too many years ago.
Are machines human-can they be?-is answered in short: “no” and “yes.” No, they are not human; they lack “intelligence.” The metaphors of Pinocchio and the Robot now entertain us for real. We have witnessed the rise of the age of computers, and the winds are shifting from an “intellectual” or “scientific” approach to the problem of “intelligence” to a technological or engineering (“expert systems”) solution, in which very large computational systems will be made to imitate our best human thinkers. We stand on the verge of an extraordinary irony: computers will become “more” human, more intellectual through an approach to intelligence which is itself, mostly non-intellectual. The dystopic vision of the movie “2001” -in which thinking computers first rid the world of humanoids, then mimic us at our most destructive-impinges uncomfortably.
But before approaching a description of what is (as far as it can be foretold) happening in the field(s) called “Artificial Intelligence,” it is useful to explore why these questions arise in the form that they do; i.e., as “intelligence.” Quite probably, the human-machine problem could be considered more broadly, as an aspect of what makes humans, Human. If we open the pages of our history, we see, however, that there are three significant counter-or anti-metaphors in terms of how we think about what is human, which equate human with intelligence. These are: animals, machines, and aliens (non-terrestrial beings, “Martians”). The question of intelligence and machines gains its substance largely in terms not of what we are; but of what we are not! As we will see, this historical habit of thought has depicted humans narrowly and less complexly, than we are…apparently.