5th century Ancient Greek philosophers Aristotle and Plato claim that animals have a low level, distinctly non-human consciousness.
1630s René Descartes says that animals are automata without feeling.
1859 British biologist Charles Darwin links humans to animal ancestors.
1949 Konrad Lorenz changes the way people see animals by showing their similarities to humans in King Solomon’s Ring.
2001 American zoologist Donald Griffin argues in Animal Minds that animals have a sense of the future, complex memory, and perhaps consciousness itself.
The idea that nonhuman animals have minds and are capable of ...