Sentience: The Invention of Consciousness

November 12, 2023 4:10 PM

In Sentience, Nicholas Humphrey distills a lifetime of study of consciousness to give a picture of how he thinks it works to be sentient--that is, to be someone for whom a sensation can be personally meaningful. From monkeys with blindsight to gorillas with nothing to think about but each other, he ranges across the research to come to a conclusion he calls qualiaphilia...consciousness becomes important because it makes life worth living, makes possible empathy, and is apparently quite attractive to potential mates. Having given us a sense of what it means to have a sense of something, he goes on to ask: Who else? Are animals sentient as well?

Spoiler: He believes mammals and birds are the most likely candidates for sentience because they're warm-blooded, and makes some interesting arguments about nerve conduction speed at warm-blooded temperatures.

posted by mittens (3 comments total)

You can get a sense of what he's thinking through a few quotes:

Regarding the experience of a young woman whose visual cortex had degraded due to treatable blindness--and became increasingly depressed once her vision was treated: "Thinking about what it would be like to have blindsight, I guessed that what made H.D.'s vision so relatively worthless was that, lacking phenomenal quality, she didn't experience it as hers: indeed, it didn't contribute to her sense of self."

Prior to meeting this patient, he had spent a good deal of time with a monkey named Helen, who had been neurologically blinded as part of an experiment but who he studied for many years; he found she was able to act in many ways as though her sight were fine--climbing trees, finding scattered treats on the floor--while in other ways, especially while anxious, she would revert to her prior blindness: "I believe that Helen's lack of visual consciousness would have shown up in the way she herself conceived of the visually guided behavior of other animals--in the way she did psychology ... Being blind to the sensations of sight, she would be blind to the idea that another monkey can see."

So what are we doing with our senses? "You respond to sensory stimulation with the makings of an action--never completed--appropriate to what's happening and how you feel about it. And then you read your own response so as to get a mental picture of it."
posted by mittens at 4:18 PM on November 12, 2023

The Origin of Consciousness in the Breakdown of the Bicameral Mind awakened me to the field.
posted by fairmettle at 2:11 AM on November 13, 2023

I read one of Humphrey's earlier books (The Inner Eye) when I was a teenager in the 1980s. He's been thinking about this stuff for a very long time.
posted by pipeski at 3:32 AM on November 14, 2023