First thing we do, let’s kill all the lawyers. King Henry VI

People have long been suspicious of “middlemen,” e.g., traders, lawyers, bankers, salesman, marketers, managers, and politicians.  For millennia, most people have suspected such middlemen of being mostly social parasites, and many “Utopian” reforms have planned to eliminate them.  Economists have faced an uphill battle arguing that middlemen usually serve important functions.  Among intellectuals, engineers and physical scientists find it especially hard to appreciate roles other than designing, building, maintaining, fueling, and distributing physical goods.

A similar scenario plays out today for the “middlemen” of our minds.  Engineers and physical scientists can see the value of big human brains for solving puzzles or making and using tools.  But such folks find it harder to see functions of play, laughter, friendship, love, music, art, stories, and consciousness. They sort of see that our best theories suggest these have important social functions, but they presume this is a temporary glitch, due to our stupidity or hostility; they can’t imagine really advanced efficient societies retaining such things.  They don’t get that coordination is hard.  So when they consider how our descendants minds may evolve in the future, they feel confident that puzzle-solving must remain, but fear that the rest will disappear.

For example, I just finished the (good) hard science fiction novel Blindsight by Peter Watts (free here), whose main theme is that consciousness is a parasite, which efficient aliens avoid.  Spoiler quotes below the fold:

You invest so much in it, don’t you?  It’s what elevates you above the beasts of the field, it’s what makes you special.  Homo sapiens, you call yourself.  Wise Man. … This consciousness you cite in your own exaltation?  Do you even know what it’s for? … It’s not in charge.  You’re not in charge.  If free will even exists, it doesn’t share living space with the likes of you. … Do you want to know the only real purpose [consciousness] serves?  Training wheels.  You can’t see both aspects of the Necker Cube at once, so it lets you focus on one and dismiss the other.  That’s a pretty half-assed way to parse reality.  You’re always better off looking at more than one side of anything.  Go on, try.  Defocus.  It’s the next logical step.  Oh, but you can’t.  There’s something in the way.  And it’s fighting back.

Evolution has no foresight.  Complex machinery develops its own agendas.  Brains—cheat.  Feedback loops evolve to promote stable heartbeats and then stumble upon the temptation of rhythm and music.  The rush evoked by fractal imagery, the algorithms used for habitat selection, metastasize into art.  Thrills that once had to be earned in increments of fitness can now be had from pointless introspection.  Aesthetics rise unbidden from a trillion dopamine receptors, and the system moves beyond modeling the organism.   It begins to model the very process of modeling.  It consumes ever-more computational resources, bogs itself down with endless recursion and irrelevant simulations.  Like the parasitic DNA that accretes in every natural genome, it persists and proliferates and produces nothing but itself.  Metaprocesses bloom like cancer, and awaken, and call themselves I.

The system weakens, slows.  It takes so much longer now to perceive—to assess the input, mull it over, decide in the manner of cognitive beings.  But when the flash flood crosses your path, when the lion leaps at you from the grasses, advanced self-awareness is an unaffordable indulgence.  The brain stem does its best.  It sees the danger, hijacks the body, reacts a hundred times faster than that fat old man sitting in the CEO’s office upstairs; but every generation it gets harder to work around this— this creaking neurological bureaucracy.   I wastes energy and processing power, self-obsesses to the point of psychosis. Scramblers have no need of it, scramblers are more parsimonious.  With simpler biochemistries, with smaller brains— deprived of tools, of their ship, even of parts of their own metabolism—they think rings around you.  They hide their language in plain sight, even when you know what they’re saying. They turn your own cognition against itself.  They travel between the stars.  This is what intelligence can do, unhampered by self-awareness.  I is not the working mind, you see. …

It’s true that your intellect makes up for your self-awareness to some extent.  But you’re flightless birds on a remote island.  You’re not so much successful as isolated from any real competition. …

“So sentience has gotta be good for something, then.  Because it’s expensive, and if it sucks up energy without doing anything useful then evolution’s gonna weed it out just like that.”
“Maybe it did. … Chimpanzees are smarter than Orangutans, did you know that?  Higher encephalisation quotient.  Yet they can’t always recognize themselves in a mirror.  Orangs can.”
“So what’s your point?  Smarter animal, less self-awareness?  Chimpanzees are becoming nonsentient?”
“Or they were, before we stopped everything in its tracks.”

Added:  A standard account of the function of consciousness:

One theory … is rapidly gaining weight, with strong evidence from research … to back up its predictions.  The idea, dubbed the global workspace theory, was first floated in 1983 by Bernard Baars. … He proposed that non-conscious experiences are processed locally within separate regions of the brain, like the visual cortex. According to this theory, we only become conscious of this information if these signals are broadcast to an assembly of neurons distributed across many different regions of the brain – the “global workspace” – which then reverberates in a flash of coordinated activity. The result is a mental interpretation of the world that has integrated all the senses into a single picture, while filtering out conflicting pieces of information.