Philosophers and psychologists call human traits like feelings, conscience, and self- awareness “qualia,” and believe that, if zombies can lack them but still look and act like us (on a really bad day), then locating consciousness entirely in human biology (“physicalism”) can’t be right.
“Physicalism allows us to imagine a world without consciousness, a ‘Zombie world’ that looks exactly like our own, peopled with beings who act exactly like us but aren’t conscious. Such Zombies have no feelings, emotions or subjective experience; they live lives without qualia. As [philosopher David Chalmers] has noted, there is literally nothing it is like to be Zombie. And if Zombies can exist in the physicalist account of the world, then, according to Chalmers, that account can’t be a complete description of our world, where feelings do exist: something more is needed, beyond the laws of nature, to account for conscious subjective experience.”
I Feel Therefore I Am, Aeon Magazine Dec. 1, 2015
To physicalists, says the article, “those are fighting words, and some scientists are fighting back”:
“In the frontline are the neuroscientists who, with increasing frequency, are proposing theories for how subjective experience might emerge from a matrix of neurons and brain chemistry. A slew of books over the past two decades have proffered solutions to the ‘problem’ of consciousness. Among the best known are Christof Koch’s The Quest for Consciousness: A Neurobiological Approach (2004); Giulio Tononi and Gerald Edelman’s A Universe of Consciousness: How Matter Becomes Imagination (2000); Antonio Damasio’s The Feeling of What Happens: Body and Emotion in the Making of Consciousness (1999); and the philosopher Daniel Dennett’s bluntly titled Consciousness Explained (1991).”
Of particular interest in that battery of academic firepower is Daniel Dennett, who has a unique take on Zombies and the consciousness “hard problem”:
“Not everybody agrees there is a Hard Problem to begin with – making the whole debate kickstarted by Chalmers an exercise in pointlessness. Daniel Dennett, the high-profile atheist and professor at Tufts University outside Boston, argues that consciousness, as we think of it, is an illusion: there just isn’t anything in addition to the spongy stuff of the brain, and that spongy stuff doesn’t actually give rise to something called consciousness.
“Common sense may tell us there’s a subjective world of inner experience – but then common sense told us that the sun orbits the Earth, and that the world was flat. Consciousness, according to Dennett’s theory, is like a conjuring trick: the normal functioning of the brain just makes it look as if there is something non-physical going on.
“To look for a real, substantive thing called consciousness, Dennett argues, is as silly as insisting that characters in novels, such as Sherlock Holmes or Harry Potter, must be made up of a peculiar substance named “fictoplasm”; the idea is absurd and unnecessary, since the characters do not exist to begin with.
“This is the point at which the debate tends to collapse into incredulous laughter and head-shaking: neither camp can quite believe what the other is saying. To Dennett’s opponents, he is simply denying the existence of something everyone knows for certain: their inner experience of sights, smells, emotions and the rest. (Chalmers has speculated, largely in jest, that Dennett himself might be a Zombie.)
“More than one critic of Dennett’s most famous book, Consciousness Explained, has joked that its title ought to be Consciousness Explained Away Dennett’s reply is characteristically breezy: explaining things away, he insists, is exactly what scientists do… However hard it feels to accept, we should concede that consciousness is just the physical brain, doing what brains do.”
Why Can’t The World’s Greatest Minds Solve The Mystery Of Consciousness? The Guardian (Jan. 21, 2015)
Zombies also appear in another current scientific inquiry: whether artificially intelligent machines can be conscious. “Who’s to say machines don’t already have minds?” asks this article. If they do, then “we need a better way to define and test for consciousness,” but formulating one means you “still face what you might call the Zombie problem.” (Oh great — so a machine could be a Zombie, too, as if there weren’t already enough of them already.)
Suppose you create a test to detect human qualia in machines, and weed out the Zombies, but who’s going to believe it if it comes back positive?
“Suppose a test finds that a thermostat is conscious. If you’re inclined to think a thermostat is conscious, you will feel vindicated. If sentient thermostats strike you as silly, you will reject the verdict. In that case, why bother conducting the test at all?”
And if conscious thermostats aren’t enough to make you “collapse into incredulous laughter and head-shaking,” then how about finding consciousness in … insects? Turns out, they, too, have a Zombie problem, according to this article, co-written by a biologist and a philosopher.
What happened to science that it’s tackling these issues, and with a straight face? I promised last time we’d look into that. We’ll do that next.
 As we saw last time, David Chalmers defined the “easy” and “hard” problems of consciousness.
 Consciousness Creep: Our machines could become self-aware without our knowing it. Aeon Magazine, February 25, 2016