Christof Koch in Nautilus:
The contrast could not have been starker—here was one of the world’s most revered figures, His Holiness the Fourteenth Dalai Lama, expressing his belief that all life is sentient, while I, as a card-carrying neuroscientist, presented the contemporary Western consensus that some animals might, perhaps, possibly, share the precious gift of sentience, of conscious experience, with humans. The setting was a symposium between Buddhist monk-scholars and Western scientists in a Tibetan monastery in Southern India, fostering a dialogue in physics, biology, and brain science. Buddhism has philosophical traditions reaching back to the fifth century B.C. It defines life as possessing heat (i.e., a metabolism) and sentience, that is, the ability to sense, to experience, and to act. According to its teachings, consciousness is accorded to all animals, large and small—human adults and fetuses, monkeys, dogs, fish, and even lowly cockroaches and mosquitoes. All of them can suffer; all their lives are precious.
Compare this all-encompassing attitude of reverence to the historic view in the West. Abrahamic religions preach human exceptionalism—although animals have sensibilities, drives, and motivations and can act intelligently, they do not have an immortal soul that marks them as special, as able to be resurrected beyond history, in the Eschaton. On my travels and public talks, I still encounter plenty of scientists and others who, explicitly or implicitly, hold to human exclusivity. Cultural mores change slowly, and early childhood religious imprinting is powerful. I grew up in a devout Roman Catholic family with Purzel, a fearless dachshund. Purzel could be affectionate, curious, playful, aggressive, ashamed, or anxious. Yet my church taught that dogs do not have souls. Only humans do. Even as a child, I felt intuitively that this was wrong; either we all have souls, whatever that means, or none of us do.
René Descartes famously argued that a dog howling pitifully when hit by a carriage does not feel pain. The dog is simply a broken machine, devoid of the res cogitans or cognitive substance that is the hallmark of people. For those who argue that Descartes didn’t truly believe that dogs and other animals had no feelings, I present the fact that he, like other natural philosophers of his age, performed vivisection on rabbits and dogs. That’s live coronary surgery without anything to dull the agonizing pain. As much as I admire Descartes as a revolutionary thinker, I find this difficult to stomach.