Stimulating sensory cortex locations by electrodes in awake subjects having neurosurgery gives a sensation in a related body part, so stimulating a left-cortex point might give a brief right-hand tingle that subjects consciously report about 500ms later (Libet, 2005). This raises the issue of whether consciousness is cause or effect:
“How are nerve cell activities in the brain related to conscious subjective experience and to unconscious mental functions?” (Libet, 2005) p32.
To find out, subjects were asked to flick a wrist when they felt like it. The EEG showed a movement readiness potential in the prefrontal cortex about 200ms before subjects reported their intention to act. Conventional science immediately took this to mean that consciousness follows the brain, like a king who thinks he rules but his advisors really run everything. If brain activities do everything, consciousness may exist but it does nothing:
“A systematic exploration suggests that every cortical site holds its own knowledge. Consider the insula, a deep sheath of cortex that is buried beneath the frontal and temporal lobes. Stimulating it can have a diversity of unpleasant effects, including a sensation of suffocation, burning, stinging, tingling, warmth, nausea or falling. Move the electrode to a location farther below the surface of the cortex, the subthalamic nucleus, and the same electrical pulse may induce an immediate state of depression, complete with crying and sobbing, monotone voice, miserable body posture, and glum thoughts. Stimulating parts of the parietal lobe may cause a feeling of vertigo and even the bizarre out of body experience of levitating to the ceiling and looking down on one’s own body.
If you had any lingering doubts that your mental life arises entirely from the activity of the brain, these examples should lift them.” (Dehaene, 2014) p153.
These results don’t mean what Dehaene thinks they do, that our mental life arises entirely from the brain, because none of the nerve regions stimulated are capable of observing anything. Explaining how a movie gets onto a screen doesn’t explain how it is observed. It is true that:
“… a whole array of mental processes can be launched without consciousness…” (Ibid, p86)
But to say that global consciousness does nothing because less conscious brain parts can act without it is like saying that the sun does nothing because I can switch on a light at night. It is true that parts of the brain can act without global consciousness, as we can react to stimuli in 200ms, before the 500ms it takes to be fully conscious, but this just implies lower and higher degrees of consciousness. It doesn’t mean that there is no conscious observation at all.
The relation between consciousness and the brain is like a viewer watching a TV. Nothing can be seen until the TV is turned on but even so, a TV can’t view itself. If physical realism (PR) is that TVs exist without viewers, then viewer realism (VR) is that viewers also exist. One can imagine a conversation between these two points of view as follows:
VR: A TV can’t view itself, so there must be a viewer out there.
PR: Not at all. When the TV is turned on, we just imagine that someone is viewing it.
VR: But a network of TVs that no-one watched would be pointless!
PR: Exactly! It’s all pointless, that’s why it doesn’t matter what we show.
VR: But we can talk to viewers watching TV by long-distance phone calls.
PR: Yes, but they are also imaginary. It’s all fake.
VR: How do TV channels change if there are no viewers?
PR: The remote control changes the channels randomly. Who knows, maybe a fly sits on it?
VR: So how do you know that viewers don’t change the channel?
PR: We did an experiment. We asked a “viewer” to call us when he changed channels and the remote control came out of standby a second before his call arrived. Hence, he didn’t do it.
VR: But how long does it take a long-range phone call to arrive?
PR: About a second.
VR: So that’s not really conclusive, is it?
PR: Its near enough. Machinery does everything, viewers don’t exist.
VR: But you watch TV so you’re a viewer too, does that mean you don’t exist?
PR: Don’t be ridiculous, of course I exist.
Libet’s flawed experiment led many to think that the brain is merely a meat machine, just as nineteenth century science thought the universe was a clockwork machine, until quantum theory proved it isn’t. This desire of scientists to prove they have no choice should be a subject of study:
“… why are so many intellectuals so intent on proving that they have no free will? (As the philosopher Alfred North Whitehead pointed out ironically, ‘Scientists animated by the purpose of proving themselves purposeless constitute an interesting subject for study.’)” (Taylor, 2019)
Evolution doesn’t do pointless. The long and short-range nerve synchronies found in every brain wouldn’t have evolved if they did nothing. Nerve synchronies take time and effort to form, and that they correlate with observation suggests that consciousness has an evolutionary benefit. This can be specified as the ability to unify observation, whether at the cell or human scale