The year was 1637 and the otherwise great Renee Descartes published Discourse on the Method, and his ideas on animals were felt for centuries to come. Descartes’ position was that non-human animals (just animals to him) did not have thoughts, could not reason, and were natural (i.e. organic) automata.
‘it seems reasonable since art copies nature, and men can make various automata which move without thought, that nature should produce its own automata much more splendid than the artificial ones. These natural automata are the animals.’ – Descartes in a letter to Henry More, February 5, 1649
Immanuel Kant continued with this tradition writing that humans were worthy of ethical considerations because they could reason; non-human animals were not deserving of this consideration.
Even today, there are a few – albeit with no scientific qualifications – that still defend the idea that animals can’t think.
“The problem is, dogs don’t think. They know no reason; they have no idea why anything happens.” – Kevin Behan, Your Dog is Your Mirror.
Luckily, that is not the prevailing notion among those who actually make a study of such things. And I would even say that it has been the position of an ever increasing number of scientists for several decades.
375 years after Descartes “bête machine,” a multi-disciplinary group of scientists met at the Francis Crick Memorial Conference on Consciousness in Human and non-Human Animals and made this statement:
We declare the following: “The absence of a neocortex does not appear to preclude an organism from experiencing affective states. Convergent evidence indicates that non-human animals have the neuroanatomical, neurochemical, and neurophysiological substrates of conscious states along with the capacity to exhibit intentional behaviors. Consequently, the weight of evidence indicates that humans are not unique in possessing the neurological substrates that generate consciousness. Nonhuman animals, including all mammals and birds, and many other creatures, including octopuses, also possess these neurological substrates.”
This may not be news to anyone with a pet. No doubt, most pet owners already felt this to be true, but scientists must follow objective evidence. One can understand why they might be late to the party.