Life’s but a walking shadow, a poor player,Macbeth
That struts and frets his hour upon the stage
And then is heard no more. It is a tale
Told by an idiot, full of sound and fury,
One morning in 2016, keepers at the National Aquarium of New Zealand arrived at work to discover the institution’s inventory of octopuses unexpectedly halved. Mild-mannered Blotchy remained in his tank, his expression revealing nothing. But Inky, his bold erstwhile companion, was nowhere to be seen.
Sometime during the night, it turned out, Inky had worked his way through a small opening at the top of the tank where a cap plate had been set slightly ajar. From there he had descended to the floor and suckered his way eight feet across it, trailing a tell-tale drippy track. At that point he slid through a six-inch-diameter, 160-foot-long drainpipe — he could probably hear water noises through it — and plopped into Hawkes Bay, an arm of the vast South Pacific. Whether resentful of his imprisonment or simply curious and adventurous, Inky had returned to the sea. He was free!
It’s hard not to see some sort of intentionality in Inky’s great escape, a crafty octopean consciousness at work. But René Descartes would have been unconvinced. According to Descartes, only humans possess the nonmaterial mind that he called the res cogitans (the realm of thought). Inky, he would have said, possesses merely corporeal materiality, so his behavior must somehow have occurred within what Descartes called the res extensa, the realm of noncognitive substantiality. Cogito ergo sum, Descartes said — one of philosophy’s most famous, and most self-centered, phrases. And something of a fallacious, or at least presumptive, one: what exactly is this “I” that he posits from the presence of thought? Descartes thought, so he thought he was somebody. He did not believe creatures such as Inky could claim the same.
But in 2012 a group of scientists publicly took issue with Descartes. The occasion was the Francis Crick Memorial Conference in Cambridge, England, focusing on “Consciousness in Humans and Non-Human Animals.” It assembled, in the words of the Declaration on Consciousness that it produced in a public signing witnessed by Stephen Hawking, “a prominent international group of cognitive neuroscientists, neuropharmacologists, neurophysiologists, neuroanatomists and computational neuroscientists.” The scientists found that by stimulating parts of animal brains, even without a neocortex (the most recently evolved part of the human brain, associated with the senses), they produced behaviors consistent with similar effects associated with emotions in humans.