Carnegie Mellon University HCII Work on these projects has finished and the  last update for this site was in 2010. The site will be maintained as a community resource.


Anthropomorphism, our tendency to make anthropomorphic attributions (see the psychology section), is at the heart of a scientific disagreement about the uniqueness of human beings. Virtually all scientists accept the fact of evolution, but new information about evolution is causing ferment about people and other species.

Left, Stairway Theory. Right, Divergent Capabilities Theory.

Darwin had a kind of stairway theory. He thought there are many "steps" between us and the great apes and chimpanzees, but the distance between us and them is one of degree and not kind (Darwin, 1871/1982, p 445). For example, in the cartoon on the left, the man drops the ball and chases it. The chimp, following the man's gaze, understands that the man is chasing the ball. In this vein, lots of research has gone into discovering the human qualities of animals and the human qualities we can build into robots.

Daniel Povinelli and Jesse Bering (2002) say that new science argues against the stairway point of view. They say people differ in kind and in degree from animals. Evolution is really about diversity and differences rather than progress up a stairway. For instance, they believe only people can take the perspective of others. In the cartoon on the right, the man drops the ball and imagines the chimp capturing it, but the chimp only understands the free ball. If the chimp goes after the ball, this happens not because the chimp understands he and the man are in competition for the same ball, but rather because he wants the ball. Povinelli and Bering say only humans have a theory of mind--can reinterpret observable events, attribute reasons and causality, and see the world as others see it. Divergent capabilities theory directs scientists and roboticists to study the unique capabilities of people and animals.


Darwin, C. (1871/1982). The descent of man. New York: Modern Library.

Povinelli, D. J., & Bering, J. M. (2002). The mentality of apes revisited. Current Directions in Psychological Science, 11, 115-119.

Scassellati, B. (2002). Theory of mind for a humanoid robot. Autonomous Robots, 12, 13-24.

More in our Bibliography.


This website promotes understanding of anthropomorphism. Our work on these projects has finished, but the website will continue to be available as a community resource.