When Aristotle claimed that humans differ from other animals because they have the ability to be rational, he understood rational to mean that we could form our views and beliefs based on evidence, ...

Chimpanzees appear to execute Rational Evidence-Weighing in complex decision-making tasks. The experiments conducted demonstrated that chimps changed their minds when presented with stronger evidence.

New research on chimpanzees is forcing scientists to rethink where the line between human and animal minds really lies. In carefully designed experiments, chimps are not just grabbing at treats or ...