Saturday, March 10, 2012

Human Understanding, Randomness, Free Will, and Delusion Part II

In Part I we explored how human beings jump to conclusions when they think they understand reality. This usually occurs when the explanation makes sense, and all of us tend to generate reasons why things are the way they are. It makes sense that understanding our genome would allow us to predict what diseases we are predisposed to developing and to try to do something to avoid getting the disease. Predict and prevent make sense. It makes sense that gene therapy should work because it is so logical and understandable. If you replace the defective gene with the correct gene you should cure the disease.

Why do we humans assume we have the capacity to understand reality?

“This what our brain does all day long. It takes input from other areas of our brain and from the environment and synthesizes it into a story.”

I still remember how excited and bewildered I was the first time I learned about split-brain patients and Michael S. Gazzaniga’s left-brain interpreter. Gazzaniga early in his career studied patients who underwent surgical severing of the corpus callosum in order to treat their intractable epilepsy. The operation cut off all communication between the left and right brain hemispheres.

"We showed a split-brain patient two pictures: A chicken claw was shown to his right visual field, so the left hemisphere only saw the claw picture, and a snow scene was shown to the left visual field, so the right hemisphere only saw that. He was then asked to choose a picture from an array of pictures placed in full view in front of him, which both hemispheres could see. The left hand pointed to a shovel (which was the most appropriate answer for the snow scene) and the right hand pointed to a chicken (the most appropriate answer the chicken claw). Then we asked why he chose those items. His left hemisphere speech center replied, “Oh, that’s simple. The chicken claw goes with the chicken,” easily explaining what it knew. It had seen the chicken claw. Then, looking down at his left hand pointing to the shovel, without missing a beat, he said, “And you need a shovel to clean out the chicken shed.” Immediately, the left-brain, observing the left hand’s response without knowledge of why it had picked that item, put it into a context that would explain it. It interpreted the response in a context consistent with what it knew, and all it knew was: chicken claw. It knew nothing about the snow scene, but it had to explain the shovel in his left hand. Well, chickens do make a mess, and you have to clean it up. Ah, that’s it! Makes sense. What was interesting was that the left hemisphere did not say, “I don’t know,” which truly was the correct answer. It made up a post hoc answer that fit the situation. It confabulated…We called this left-hemisphere process the interpreter.” (Who’s In Charge? Free Will and the Science of the Brain, New York: HarperCollins, 2011)

Does it bother you as much as it does me that when my brain cannot truly understand what is going on, it decides to make up a story? Does it bother you that we are hardwired to confabulate? How can I be sure that the story I am telling myself is consistent with the truth? How can I be sure I know what is going on?

Science must be able to help me out here. After all science searches for what we can establish as justifiably true. Physicist James Cushing has written that science “requires at a minimum that our scientific theories are to be taken as giving us literally true descriptions of the world.” (Philosophical Consequences of Quantum Theory, Notre Dame, Indiana: University of Notre Dame Press, 1989) Ten out of 11 physicists “claimed that what they were describing with their symbols and equations was objective reality,” according to mathematician John Casti. (Paradigms Lost, New York: William Morrow and Company, 1989) I am feeling like I am on a little firmer ground here.

That is, until I remember Kurt Godel and Edmund Gettier. Godel proved that mathematics powerful enough to do arithmetic could not be both consistent and complete when he wrote a correct equation that said this statement cannot be proven. Gettier confused me when he showed one can have a justified, true belief and still have no idea what is going on. Gettier’s thought experiment was to imagine a man who believes there is a sheep in a field because he mistakes the dog he sees for a sheep. However, behind a large rock there is indeed a sheep that the man cannot see. Even though the three criteria for knowledge (belief, justification, and truth) are met, it is hard to say this man knows what is going on. After all, what he knows is based on his mistaking a dog for a sheep.

(Steve Hagen, How the World Can Be the Way It Is: An Inquiry for the New Millennium into Science, Philosophy, and Perception, Wheaton, Illinois: Quest Books, 1995)

The astronomer John Barrow notes “the practice of science…rests upon a number of presuppositions about the nature of reality.” He identifies nine such presuppositions:

· The external world is external to our minds and is the source of our sensations.

· The external world is rational

· The world be analyzed locally without destroying its structure

· The elementary entities do not possess free will.

· The separation of events from our perception of them is a harmless simplification

· Nature possess regularities which are predictable

· Space and time exist

· The world can be described by mathematics

· These presuppositions hold in an identical fashion everywhere and everywhen. (The World Within the World, New York: Oxford University Press, 1988).

Lys Ann Shore and Karl Popper add to my doubts that science will tell me what is really going on. Shore has written, “The quest for absolute certainty must be recognized as alien to the scientific attitude, since scientific knowledge is fallible, tentative, and open to revision and modification.” (Hagen, 1995) I would guess that Shore, like Nassim Nicholas Taleb, has been influenced by Karl Raimund Popper’s ideas about the philosophy of science.

The Stanford Encyclopedia of Philosophy summarizes Popper’s philosophy of science (

“Scientific theories, for him, are not inductively inferred from experience, nor is scientific experimentation carried out with a view to verifying or finally establishing the truth of theories; rather, all knowledge is provisional, conjectural, hypothetical—we can never finally prove our scientific theories, we can merely (provisionally) confirm or (conclusively) refute them; hence at any given time we have to choose between the potentially infinite number of theories which will explain the set of phenomena under investigation. Faced with this choice, we can only eliminate those theories which are demonstrably false, and rationally choose between the remaining, unfalsified theories. Hence Popper's emphasis on the importance of the critical spirit to science—for him critical thinking is the very essence of rationality. For it is only by critical thought that we can eliminate false theories, and determine which of the remaining theories is the best available one.”

Popper thought there are only two kinds of scientific theories: those that have been proven to be wrong and those that have yet to be proven wrong.

Part III will continue to explore how we can understand what is going on in the world.

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