A THEORY OF INTELLIGENCE: How much brain needed? (Identity)

by David Turell , Saturday, July 07, 2018, 23:18 (2330 days ago) @ David Turell

It turns out from patient's examples only a partial brain is needed for excellent intelligence, but some folks are not as fortunate and don't function well. Egnor makes great case for the existence of the soul:

https://www.plough.com/en/topics/justice/reconciliation/science-and-the-soul

" How does the mind relate to the brain? This question is central to my professional life. I thought I had it answered. Yet a century of research and thirty years of my own neurosurgical practice have challenged everything I thought I knew.

"The view assumed by those who taught me is that the mind is wholly a product of the brain, which is itself understood as something like a machine. Francis Crick, wrote that “a person’s mental activities are entirely due to the behavior of nerve cells, glial cells, and the atoms, ions, and molecules that make them up and influence them.”

"This mechanical philosophy is the result of two steps. It began with Rene Descartes, who argued that the mind and the brain were separate substances, immaterial and material. Somehow (how, neither Descartes nor anyone else can say) the mind is linked to the brain – it’s the ghost in the machine.

***

"Computer functionalism came next: the brain is hardware and mind is software. But this too has problems. Nineteenth-century German philosopher Franz Brentano pointed out that the one thing that absolutely distinguishes thoughts from matter is that thoughts are always about something, and matter is never about anything. This aboutness is the hallmark of the mind. Every thought has a meaning. No material thing has meaning.

***

"Remarkably, neuroscience tells us three things about the mind: the mind is metaphysically simple, the intellect and will are immaterial, and free will is real.

***

"The neuroscientist Roger Sperry studied scores of split-brain patients. He found, surprisingly, that in ordinary life the patients showed little effect. Each patient was still one person...The most remarkable result of Sperry’s Nobel Prize­–winning work was that the person’s intellect and will – what we might call the soul – remained undivided.

***

"First, he noticed something about seizures. He could cause seizures by stimulating the brain. A patient would jerk his arm, or feel tingling, or see flashes of light, or even have memories. But what he could never do was cause an intellectual seizure: the patient would never reason when his brain was stimulated. The patient never contemplated mercy or bemoaned injustice or calculated second derivatives in response to brain stimulation. If the brain wholly gives rise to the mind, why are there no intellectual seizures?

"Libet began by choosing a very simple thought: the decision to press a button. He modified an oscilloscope so that a dot circled the screen once each second, and when the subject decided to push the button, he or she noted the location of the dot at the time of the decision. Consistently he found that the conscious decision to push the button was preceded by about half a second by a brain wave, which he called the readiness potential. Then a half-second later the subject became aware of his decision. It appeared at first that the subjects were not free; their brains made the decision to move and they followed it.

"But Libet looked deeper. He asked his subjects to veto their decision immediately after they made it – to not push the button. Again, the readiness potential appeared a half-second before conscious awareness of the decision to push the button, but Libet found that the veto – he called it “free won’t” – had no brain wave corresponding to it.

"The brain, then, has activity that corresponds to a pre-conscious urge to do something. But we are free to veto or accept this urge. The motives are material. The veto, and implicitly the acceptance, is an immaterial act of the will.

***

"Aquinas wrote that the human soul has distinct kinds of abilities. Vegetative powers, shared by plants and animals, serve growth, nourishment, and metabolism. Sensitive powers, shared with animals, include perception, passions, and locomotion. The vegetative and sensitive powers are material abilities of the brain.

"Yet human beings have two powers of the soul that are not material – intellect and will. These transcend matter. They are the means by which we reason, and by which we choose based on reason. We are composites of matter and spirit. We have spiritual souls.

***

"Philosopher Roger Scruton has written that contemporary neuroscience is “a vast collection of answers with no memory of the questions.” Materialism has limited the kinds of questions that we’re allowed to ask, but neuroscience, pursued without a materialist bias, points towards the reality that we are chimeras: material beings with immaterial souls."

Comment: As far as I am cencerned the soul exists.