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Our future, our universe, and other weighty topics


Wednesday, July 19, 2017

Future Humans with Enhanced Imaginations May Have No Need for Virtual Reality

The idea of virtual reality has been around for decades. You put on a pair of goggles, and suddenly you find yourself immersed in a computer-generated 3D world. Technology has been slow at bringing this idea to fruition, but this is an area where we can be very confident that spectacular progress will be made. There are absolutely no theoretical roadblocks to creating an extremely vivid 3D landscape that you can view with virtual reality goggles. Making virtual reality a household reality is just a matter of making more progress in visualization technology that has been progressing at a high rate of progress for decades. No doubt within twenty years, you will be able to have spectacular virtual reality experiences at a reasonable cost.

But what about interacting with the 3D world you see while wearing the virtual reality goggles? It will be hard for an interface to allow seamless interactions. Someone wearing virtual reality goggles may be able to manipulate a controller with his hands, maybe something like a video controller. But this creates a kind of imperfect blend. You are using your hands (which you cannot see with the goggles on) to interact with the world you view while wearing the goggles. And what if you want to interact with the virtual world or its inhabitants in a way that the simple controller doesn't allow? For example, in the virtual world you might want to kiss a character on the cheek, but your simple controller may offer no way to do that.

Another idea for interacting with a computer-generated reality is an idea advanced on the TV show Star Trek: The Next Generation: the idea of a holodeck. The idea is that you go into some special room where there are very sophisticated holographic projectors. All of the walls, the ceiling, and the floor of the holodeck are involved in the holographic projection. So after entering such a room, you might suddenly find yourself seeing just what someone would see at the Grand Canyon. You look all around, and everything looks just as it would if you were in the Grand Canyon, even at your feet. You may also interact with what looks like other people, but these too are just holographic projections.  There is no need to wear any special goggles.

The basic idea of a holodeck seems technically feasible, although in both Star Trek: The Next Generation and Star Trek: Voyager, the idea was stretched to what seemed like unrealistic extremes, as we would see people using the holodeck sitting on holographic chairs and lying on holographic beds. It would seem that a holographic projection would offer no such solidity.

The main drawback of a holograph is that it isn't a “use around the house” kind of thing, requiring a large expensive room capable of sophisticated holographic projection. Another drawback is that a holodeck seems unsuitable for a simulation in which you are walking around for long distances, such as a simulation in which you are walking around on the streets of a city.

But there's another idea for how future humans could experience something like virtual reality, an idea rarely considered. The idea is to somehow upgrade human imagination. If human imagination were somehow to be expanded far beyond its current limits, then people might have within their own minds something that would be better than virtual reality or a holodeck.

Consider the human imagination. Any one of us can conjure up a “movie in our minds,” in which we can imagine anything we can please. But what we see in our mind's eye when we daydream is kind of pale, dim, and shadowy, without many details. But imagine if that “movie in our minds” could somehow become as detailed and vivid and life-like as a widescreen IMAX movie.  And imagine if we could fill in endless imaginative details effortlessly.



Such a thing might be possible in the future, given some imagination upgrade in the human mind that might be achieved through technology, neural implants, drugs, or genetic enhancements. After such an upgrade, you might have no need for VR goggles or a holodeck. You could simply close your eyes and see in your mind's eye something that might be as vivid as virtual reality or a modern video game on a wide-screen TV. And you could shape that very-vivid reality effortlessly, just by imagining something different. In your mind's eye you could move from one city to another effortlessly, or from one planet to another planet, seeing each one as vividly as if you were watching a wide-screen movie. A hundred vivid details might flow into such scenes, flowing effortlessly from the wellsprings of your enhanced imagination.

It might be dangerous to make such an imagination upgrade a permanent part of the human mind. For with such an imagination, prisons would not be such a deterrent. Every prisoner would know that from his jail cell he could have something as enjoyable as trips to a thousand Disney Worlds, just by closing his eyes and letting his imagination gush forth.

Saturday, July 15, 2017

Why Don't More Scientists Use Something Like the IPCC's Probability Scale?

The Intergovernmental Panel on Climate Change (IPCC) is the main scientific body that studies global warming. Although it takes some heat from the skeptical, it seems that in a broad sense the IPCC has done two things right.

The first thing it has done right is to avoid making only one projection of future global warming until the year 2100. Given all the uncertainties, it would be very dogmatic to do such a thing. Instead of publishing only one projection, the IPCC publishes a variety of different scenarios, which have names such as RCP8.5, RCP6.0, RCP4.5, and RCP2.6. Some of them are shown in the graph below (from this document).

The climate change implications of these scenarios are shown in the next IPCC graph, which uses a color-coding scheme matching the one used in the previous graph. So we see that the RCP 8.5 scenario (requiring a total carbon dioxide emission of about 6000 gigatons or more) translates into a very damaging 3.5 Centigrade increase in global warming. But the RCP2.6 scenario and the RCP 4.5 scenario (involving only about 3 or 4 gigatons of carbon dioxide emission) result in a much smaller increase of between 1.5 and 2..0 Centigrade. 

 
Now, you could argue that the RCP 8.5 scenario will never occur, on the grounds that we will never be extract so much carbon dioxide (6000 gigatons or more). The International Energy Agency estimates that the total world reserves of coal are only about 892 billion tons, and much of that is hard-to-extract coal that may never be extracted because it is not economically feasible to extract.

But given the IPCC's approach of providing widely different scenarios, such an objection does not damage its credibility. For one of its other scenarios such as RCP 2.6 or RCP 4.5 may still be valid, despite such an objection. Given its differing scenarios allowing such a variety of outcomes, we really can't fault the IPCC for being too dogmatic in this regard.

There's another thing that is good about the IPCC approach: the fact that it uses a probability scale. The IPCC has a scale that looks like this:

 
These probability assessments are used in the IPCC's Fifth Assessment report. So rather than the report speaking as if it was 100% certain about everything, we are told that some things are likely, other things are very likely, and other things are as likely as not.

The use of such a likelihood scale is to be commended, because there is a great deal of uncertainty in our understanding of nature. If scientists are not sure about something, it is is good that they state assertions in a shaded away, expressing only moderate confidence or low confidence.

It would be good if other sciences followed such an approach. But do we find such a likelihood scale used in fields such as biology, physics, neuroscience or cosmology? No, we do not.

The general tendency in contemporary science is to follow a very different approach. It is as if there were two big lists: the list of approved doctrines, and the list of disapproved doctrines. All of the items on the list of approved doctrines are pretty much taught as if they were gospel truths. This is not too different from the way that the Catholic Church teaches religious doctrines.

Once some teaching somehow manages to get on this list of approved doctrines, the doctrine has it “made in the shade.” We are then told that there is a scientific consensus, so it's kind of “case closed.”

But what if a different approach was taken, an approach using a probability scale, like the IPCC is using? The results would be salutary. There would no more be a situation in which doctrines could endlessly “rest on their laurels.” Each scientific teaching would have to be graded on a probability scale. If such a probability scale was used honestly, it would soon become apparent that some of the theories that have chewed up the most research funding have a not-very-high ranking on the probability scale.

It would be best to make use of a probability scale rather different from the one used by the IPCC. The scale below would be better suited for grading a wide variety of scientific assertions.

Almost certain Greater than 99% likelihood
Very likely Greater than 90% likelihood
Likely Greater than 50% likelihood
Quite possible Greater than 5% likelihood
Possible Greater than 1% likelihood
Remotely possible Less than 1% likelihood
Apparently impossible Apparently no likelihood


I can imagine a two-phase exercise to make use of such a scale. In the first phase, you begin with a chart like the one below. You draw colored lines between the items on the left and the items on the right, using a different color of ink for each level of confidence.

probability scale
So the end result might look something like this:

probability scale

In the second phase of the exercise, you would be required to justify each case in which you had specified that one of the items on the left had a probability of “quite possible” or higher. This would require actually presenting observations or experiments that show there is a basis for concluding a likelihood of at least 5%. Appeals to current popularity or a consensus of agreement would not be allowed.

Let us imagine how clarifying such an exercise would be. Using such a scale in the area of physics and cosmology would throw light on how much of modern theoretical physics is on shaky ground. For example, there would be no basis for giving either the theories of supersymmetry or string theory a probability grade of higher than “remotely possible” or “possible.” The fact that such theories are widely popular would be no basis for granting them an assessment of “quite possible” or “likely.”

Using such a likelihood scale sounds like a great idea, so why is such a scale not used in fields such as cosmology, physics, and biology? I suspect the reason is that using such a scale would involve introducing a level of humility that today's dogmatic theoretician would prefer to avoid.

Consider the dogmatic scientific theorist. He may advance some theory unlikely to be true. But he would rather that people not judge his theory based on some scale in which it is judged whether the theory is “quite possible,” “likely” or “very likely.” Because then it might become clear that there is no basis for concluding that the theory is probably true. Such a theorist would prefer the current approach, in which it is as if there is a “list of approved doctrines,” and you are supposed to accept all the items on the list. Having got his theory on such a list (often because of sociological considerations), such a theorist would not want there to be a system in which scientists use varying shades of confidence in their assertions. It might then become apparent to all that the theorist's pet theory is not on very firm ground. 

Similarly, an apologist for an organized religion would never want you to make use of some exercise like the one above, in which you drew lines specifying whether 15 assertions of his creed were “possible,” “quite possible,” “likely,” “very likely,” or “almost certain.” He would instead want you to accept the whole creed with complete confidence, regarding every item in it as a certainty.

Like such a theological apologist, the modern pitchman for the "official party line" of modern science would rather that you not use probability scale ratings that might make his "standard story" look like something that is largely speculative, largely a kind of social construct in which many a predominant theory is more of a speech custom than something that has been established as a likelihood.

Tuesday, July 11, 2017

Cosmic Coincidence Cover-Up

In a recent post entitled “The Universe Itself May Be Unnatural,” cosmologist Ethan Siegel discusses some issues that he calls “coincidence problems.” He says, “If aspects of the Universe that should be very different turn out to be similar, we call this a "coincidence problem." He discusses some cosmic coincidences, but neglects to discuss the most dramatic ones, including the “vacuum catastrophe” issue discussed here, and the issue I will discuss in this post: the coincidence of the proton charge being the exact opposite of the electron charge.

As many a scientist has admitted in recent decades, the fundamental constants of the universe are very fine-tuned to allow the existence of living creatures such as us, in the sense that there are quite a few “coincidences” required for our existence, lucky breaks that we needed and just happened to get. Any fully informative listing of the universe's fundamental constants should show at least one such coincidence, standing out very plain for the eye to see. Such a listing would look like this:

Fundamental Constants

Speed of light 299,792,458 meters per second
Planck's constant 6.62607004 × 10-34 m2 kg / s
Gravitational constant 6.67408 × 10-11 m3 kg-1 s-2
Proton mass 1.6726231 × 10-27 kg
Electron mass 9.1093897 × 10-31 kg
Proton charge 1.60217733 × 10-19 coulomb
Electron charge -1.60217733 × 10-19 coulomb

As we can see in this accurate listing, there is a great big coincidence. Even though each proton has a mass 1836 times greater than each electron, the charge of the proton is the exact opposite of the charge of the electron. An absolute magnitude is a number that you get when you discard the sign in front of the number. Experiments have actually indicated that the absolute magnitude of the proton charge and the absolute magnitude of the electron charge differ by less than 1 part in 1,000,000,000,000,000.

But if you do a Google search looking for listings of the fundamental constants of nature, you are not likely to notice this coincidence involving the proton charge and the electron charge. Why is that? It's because almost all of the tables of fundamental constants you will see will have concealed the coincidence.

Imagine some bank employee named John Wilson who each day is supposed to send out an email to his superiors entitled “Today's most important transactions.” On a particular day such an email might honestly include the following:

Money we lost overnight in bank robbery: $1,345,239
Today's biggest deposit (to account of John Wilson): $1,345,239

Of course, this coincidence is very embarrassing to Mr. Wilson, as it suggests that the bank robbery was what they call an “inside job.” So Wilson would no doubt arrange his table of “today's important transactions” so that it somehow covered up the coincidence. Similarly, almost always modern scientists creating a table of fundamental constants of the universe will arrange the table in such a way so that no one can notice any coincidence involving the charge of the electron and the proton. For they don't want anyone to think that the universe is something like “an inside job.”

A convention is followed as to how this concealment is done. The convention is to avoid listing both the proton charge and the electron charge, and to list a single value that is called “the elementary charge.” So the table of fundamental constants will look like this:

Fundamental Constants

Speed of light 299,792,458 meters per second
Planck's constant 6.62607004 × 10-34 m2 kg / s
Gravitational constant 6.67408 × 10-11 m3 kg-1 s-2
Proton mass 1.6726231 × 10-27 kg
Electron mass 9.1093897 × 10-31 kg
Elementary charge 1.60217733 × 10-19 coulomb

This “elementary charge” is supposed to represent both the charge of the proton and the charge of the electron. Is it honest and accurate to be using such a term for both the positive charge of the proton and the negative charge of the electron? No, it isn't. Since the electron charge is negative and the proton charge is positive, it is misleading and inaccurate to use a single positive value to represent both of these things. It is as  misleading as representing both a $1000 withdrawal and a $1000 deposit under a single line giving a positive number. For example, you would be misleading your mortgage lender if you withdrew $20,000 one day and then re-deposited it the same day, and then emailed your mortgage lender with a line such as this:

Today's bank activity: +20,000

The convention followed in tables of fundamental constants of listing both the proton charge and the electron charge under a single “elementary charge” line listing a positive value is therefore a deceptive concealment. It is a concealment because it hides from us a fundamentally important fact that we should be informed about, that there is a huge coincidence in nature involving the proton charge being the exact opposite of the electron charge. The concealment is deceptive (in the sense of being literally inaccurate) in the sense that after looking at tables of fundamental constants that follow this convention, you will be left with the very inaccurate idea that the electron charge is positive.

Moreover, in physics the term “elementary” is used to mean something that cannot be reduced any further, as in the phrase “elementary particles” which refers to particles which cannot be subdivided any further. But we know that the proton charge is not even elementary in this sense. A proton is believed to consist of two Up quarks which each has a charge of 2/3 of the proton charge, and one Down quark which has a negative charge of 1/3 of the proton charge. So as the proton charge is not at all elementary, it is misleading to be listing it in a line labeled “elementary charge.”

There is quite a bit of talk in the news these days about obstruction of justice. What we have going on in the typical table of fundamental constants is what we can call an obstruction of learning. The person who bothered to view such a table should have been informed of the basic fact that the proton has a charge that is the exact opposite of the charge of the electron. Such a person is obstructed from learning this important fact by the typical table of fundamental constants, just as if the scientist creating the table was interested in covering up such a fact, and sweeping it under the rug.

sweeping under rug


The “elementary charge” concealment trick is used in many different physics references, but very rarely a physicist will let down his guard and “spill the beans.” That's what happens in the informative and entertaining new book We Have No Idea by physics professor Daniel Whiteson and Jorge Cham (which has many fun little cartoons which make it easier to read than a typical book on science). On page 54 the authors state this:

If the quarks had any more (or less charge), then the charge of protons wouldn't precisely balance the negative charge of the electron, and you couldn't form stable neutral atoms. Without these perfect -1/3 and + 2/3 charges, we wouldn't be here. There would be no chemistry, no biology and no life.

But is there any explanation for this? Apparently not, because the authors next state this:

This is actually fascinating (or creepy, depending on your level of paranoia) because, according to our current theory, particles can have any charges whatsoever; the theory works just as well with any charge value, and the fact they balance perfectly is, as far as we know, a huge and lucky coincidence.

It's not just one coincidence but two coincidences. The first coincidence is that the absolute magnitude of the charge of the Up quark is exactly twice the absolute magnitude of the Down quark. The second coincidence is that when you add up the charges in a proton (consisting of two Up quarks and one Down quark), you get a charge that is the exact opposite of the charge of the electron. As far as we can tell, these are separate coincidences, each with a likelihood no better than 1 in 1,000,000,000,000,000. The chance of both occurring in nature is like the odds of you correctly guessing the telephone numbers of two strangers, and then correctly the guessing the telephone numbers of the next two strangers you met. 

The use of the word "creepy" in the quote above is interesting, as if the authors were afraid of learning about some contrivance in nature needed for their own existence. Would not "wondrous" be a more suitable adjective? 

Postscript: The universe's fundamental constants are correctly listed at this page, one of the few listings that correctly has separate lines for the proton charge and the electron charge, using a positive sign for the proton charge and a negative sign for the electron charge. 

Friday, July 7, 2017

The Election Tamperers: A Science Fiction Story

Susan Tyler never thought she would see her young brother George again when she said a tearful goodbye to him on the day before the interstellar mission left. It was the first manned mission to another star, on the mighty interstellar spaceship named Starbird. The 120 crew members had been trained to establish a colony on one of the planets revolving around Alpha Centauri, several light-years away.

Using the latest antimatter drive technology, the spaceship traveled at about one-third of the speed of light. It took 13 years for the ship to reach Alpha Centauri. The ship beamed a radio message saying that an apparently habitable planet had been detected. The nations of Earth were thrilled by the announcement.

But then there was a long radio silence. People asked: had something terrible happened? For weeks, everyone would check the news day after day, waiting for a new radio signal from the spaceship. But no signal was received. The weeks turned into months, which turned into years. Eventually the public reached the sad conclusion that something terrible had gone wrong, and that no signal would ever be picked up from the doomed mission. Susan Tyler reconciled herself to the idea that her brother George must be dead.

What happened thirteen years later was almost as shocking as the sudden radio silence from Alpha Centauri. Astronomers detected a spaceship entering the solar system. At first people thought it might be some extraterrestrial spaceship. But before long, astronomers announced something shocking: the spaceship was Starbird, the very spaceship that had left for Alpha Centauri 26 years ago. 



The ship's crew docked at a space station, and then returned to Earth. The ship's captain gave a press conference announcing what had happened.

We approached the planet revolving around Alpha Centauri, and at first we thought it might be a habitable planet with life,” said Captain Horton. “But when we got closer we were disappointed to find it was just rocky and moon-like, with no signs of life. So we decided to just turn around and come back to Earth. We were going to radio our findings, but a meteorite damaged our radio antenna.”

The story seemed strange, and raised eyebrows around the world. But most people accepted it.

Susan Tyler welcomed George back to the town where she and her parents lived, and she thought: this is so strange, I never thought I'd see him again. She was not surprised that George looked 26 years older. But she was surprised by his cold, humorless demeanor. She remembered her brother as a very warm and funny person.

What are you going to do now?” asked Susan.

I'm going to do what quite a few of my fellow astronauts are going to do,” said George. “I'm going to run for President.” He explained that quite a few of his astronauts had developed political ambitions on the long trip home from Alpha Centauri. A German was going to run to become president of the European Union. A Russian was going to run to become president of Russia. A Chinese astronaut was going to run to become the president of China, which had become a democracy 30 years ago.

Over the next few weeks, Susan began to develop suspicions about George. Although he seemed to think very fast, he seemed to have a very different personality than the George she remembered. Funny warm George had somehow turned into cold, humorless George. He also seemed to have no memory of the childhood they had shared. He would also never eat any food when he was at a family gathering, and would never drink anything.

Susan discussed her suspicions with her mother, her father, and her sister Betty. They all agreed that George somehow wasn't the George they knew. The family began asking George questions he couldn't answer. Their suspicions were also raised by the fact that George lived in a house in which the windows were always covered up. George would never invite any other family members over.

Susan's suspicions about George began to eat away at her. One day she decided to wait until George opened his door, and then barge into his house. She would look around before George had a chance to throw her out.

Susan did just that. She hid behind a bush near George's door. When he opened the door, Susan rushed in.

I didn't invite you in!” said George. “Get out of here!”

I'll be out in just a second,” said Susan, running around. She went down to the basement. She let out a scream when she saw what was in the basement.

In the basement were four tables. On the tables were what looked like the bodies of her father, her mother, and her sister.

You fiend!” screamed Susan. “What have you done with Mom, Dad, and Betty?”

Oh don't worry, those aren't Mom, Dad, and sister Betty,” said George. “But they will be soon.”

What are you talking about?” said Susan, horrified.

I guess it's time I told you the whole story,” said George. “When the Starbird reached the planet at Alpha Centauri, its crew members didn't find a lifeless rock like you were told. They found a thriving life-filled planet with a civilization much older than yours. The crew members of the Starbird were all arrested. I'm not your brother – he's still at Alpha Centauri.”

So who are you?” asked Susan.

I'm a replicant of your brother – what you would call a robot,” said George. “The Alpha Centaurians hatched a plot to control your planet. They decided they would send back to Earth the spaceship you sent to their planet, but its crew would not be the original crew – it would be a crew of robotic replacements like me. We were all told to run to become the leader of a country. The plan is to have us robots take over some of the key nations of your planet. So when Alpha Centauri sends its invasion fleet to Earth, things will be much easier. We'll already have control over some of the main nations on Earth.”

So what are these bodies on the tables?” asked Susan.

They're the robot replacements for George's family members,” said George. “I built them myself. You see, if I'm going to successfully run for President, I can't have George's family members saying things like 'there's something real weird about George' or 'we have all these suspicions about George.' I need to have someone who will say, 'George is the same fine fellow I knew before.' ”

George went over to a table that had a blanket over it.

Do you want to see the latest robot I created?” asked George. George removed the blanket. It was a naked robot looking just like Susan. George flicked a remote control unit, and the robot stood up.

Hello, my name is Susan Tyler,” said the robot, “and I think George Tyler would make a wonderful president of the United States.”

Susan screamed, and began to run up the basement stairs. George grabbed her by the throat. I'm doomed, thought Susan.

It's pointless to resist our scheme,” said George icily as he strangled Susan with his hands. “The Alpha Centaurians are older and more powerful. Earth will fall.”

But just then police officers broke open the front door. Armed with machine guns, they stormed into the house, and quickly found Susan and George, who were both arrested.

Susan told the whole story to the police. No one would have believed her wild story, were it not for the fact that the robots were still lying on the tables on the basement.

Faced with the undeniable evidence against him, robot George finally confessed.

How did you ever find out enough to come to my house?” asked George.

We didn't know a thing about all this weird robot space stuff,” answered a police official. “While you were manufacturing those robots, a pungent smell was coming from your house. Plus your windows were all closed up. One of your neighbors got suspicious, and reported your house as one of those houses where they illegally manufacture drugs. At the time we stormed in on what we thought was a drug bust, we thought your house was just a regular old crystal meth lab.”

Monday, July 3, 2017

Exaggerations Abound When People Talk About a Scientific Consensus

One of the most powerful argumentative techniques in favor of some truth claim is to assert that there is some consensus of opinion among scientists that the claim is correct. But often such assertions are unwarranted. Quite a few of the times that people claim that there is a scientific consensus on something, there is no actual majority of scientists who assert such a thing. Below are six reasons for thinking that quite a few claims of scientific consensus are exaggerated, and are not matched by an actual majority opinion of scientists on the matter in question.

Factor #1: Claims of Consensus Are Often Made Before a Consensus Is Reached

Let's imagine that there's some theory that is starting to get traction in the scientific community. Imagine you are some advocate for the theory, trying to get even more people to accept it. What is your easiest route to such a goal? It is to claim that there is a scientific consensus in support of this theory you support. Many people will meekly fall into line and accept your theory, as soon as they hear a claim that most scientists have accepted the theory. The temptation to claim “most scientists believe this” is so great that people often make such claims even when no such consensus has been reached.

Factor #2: Most People Who Claim a Scientific Consensus Offer No Evidence

The great majority of statements claiming a scientific consensus on something offer no evidence to back up for such a claim. For every time that someone claims that most scientists agree on something, and tries to back up such a claim by referring to some opinion poll or study of scientific opinion, there must be ten or twenty times that someone claims that most scientists agree on something without offering any evidence to back up the claim.

Factor #3: There Typically Exist No Formal Processes for Identifying the Opinions of Scientists on Theories

Given the fact that people are often claiming that most scientists think such-and-such a thing, it is rather surprising to consider that there typically exists no systematic process for having scientists state their opinions on whether particular theories are true. In the world of science, there is nothing equivalent to the voting booth. For example, scientists are not sent annual questionnaires in which they are asked to rate the likely truth of different theories on a scale of 1 to 10, with 10 being certainty about a particular theory.

So when people claim that most scientists believe this or most scientists believe that, and try to back up their claims with some evidence, they may refer to opinion polls or a survey of the scientific literature. These are very imperfect measures of opinion, for reasons discussed below.

Factor #4: People Often Self-Censor Private Opinions Conflicting With Perceived Norms

In November of 2016 there was a startling result in the American presidential election. Donald Trump won a victory in the electoral college, despite losing the popular vote by millions. This was despite both late election polls showing him losing by a substantial margin, and also Election Day exit polls showing him losing in some of the key states he won. A reasonable idea to explain this is the idea of self-censorship. This is the idea that when people hold opinions that differ from perceived norms, they often never publicly state such opinions, and will only express them in something like a secret ballot. It may be that a significant percentage of voters planned to vote for Trump, but told pollsters otherwise, as they regarded their support of Trump as something that conflicted with perceived norms.

We have no idea how much self-censorship plays a role in scientific opinion. Many a scientist may disagree with theories that are supposedly supported by a majority of scientists. Such scientists may engage in self-censorship, figuring that it is not a good career move to speak in opposition to some theory that many other scientists are supporting. This makes it harder to determine just what the majority of scientific opinion really is. 

An example of self-censorship

Factor #5: It Is Very Hard to Unravel the Level of Support for a Theory Based on Scientific Papers

Since scientists have no formal process for voting on the truth of theories, some people have attempted to use studies of scientific papers to draw conclusions about a scientific consensus on some topic. Such attempts can be problematic.

An example of an analysis of scientific papers that offers limited insight is this study, which has been widely although inaccurately summarized as reporting a 97% consensus about anthropogenic global warming. It is probably correct that a majority of scientists do believe that mankind is the main cause of global warming, although the study does not back up the claim of 97% consensus. For one thing, the study was based only on abstracts, those short summaries that appear at the top of a scientific paper. Secondly the study actually reported that 66% of the abstracts reported no opinion about man-made global warming. The 97% figure was from a second phase that sent a questionnaire to those who had already stated an opinion in their abstract about whether humans cause global warming. Of those people, only 14% responded; and of those 14%, 97% supported anthropogenic global warming either explicitly or in a weaker implicit sense. It is not correct to extrapolate from such a fraction of a fraction and make the same 97% claim about the scientific community in general, particularly given the dubious business of getting that 97% by lumping together explicit endorsements of anthropogenic global warming and merely implicit endorsements that may be more nuanced and ambiguous.

Page 15 of this Pew poll of scientists indicates that only 89% of them agreed that earth is warming mostly due to human activity, and that only 77% of them agreed that global warming is a very serious problem. This suggests a consensus about this topic much less than the 97% figure cited (I agree with the 89% on this topic).

It would also be extremely problematic for someone to draw conclusions about a scientific consensus based on an analysis of scientific papers on topics such as cosmic inflation or string theory. Let us consider a physicist who has become familiar with the arcane speculative mathematics of string theory or cosmic inflation theory. Such a physicist learns that he can make a comfortable living grinding out speculative papers offering yet another twist on these theories. But suppose this scientist publishes five papers on such a topic. Does it mean he actually believes the theory is likely to be true? We cannot tell. It could be that the physicist is simply interested in the mathematics, and finds that he can fulfill his yearly quota of scientific papers by writing on the topic. Such a thing does not tell us whether the scientist believes such theories to be true.

Factor #6: Opinion Polls Of Scientists Can be Misleading or Confusing Because of the Way They Are Phrased

Pros in the political field know that the way questions are worded can have gigantic effects on the results. For example, if a question asking about support for abortion is worded from a pro-choice perspective, it will get some answer suggesting a very high support for allowing abortion. The same question worded from a “protect the unborn child” perspective may show a vastly different level of support for allowing abortion.

The same principle holds true in regard to polls of scientists about scientific theories. For example, a Pew opinion poll asked a question of scientists that seemed designed to produce the highest level of response: a question asked whether they agree that “humans and other living things have evolved over time.” That got a 98% yes response. But “evolved over time” could mean small-scale stuff, what is known as microevolution. A scientist believing in small-scale evolution may answer “Yes” to such a question, even though he doesn't believe in the origin of species from more primitive species, or does not believe that such a thing is mainly caused by natural selection. 

Very absurdly, the Pew poll question gave respondents a choice between asserting that "Humans and other living things have evolved over time" and "Have existed in their present form since the beginning of time."  Such a choice forces anyone believing in a 13-billion-year-old universe to choose the first answer, since there is no option such as "Humans originated for unknown reasons about 100,000 years ago, long after the Big Bang." This is a classic pollster's goof: make it seem like almost everyone believes in choice A by offering a choice between choice A and some choice B that almost no one would accept. 

What if these questions were asked:

Is it true that humans have evolved from ape-like ancestors?
Is it true that humans have evolved from ape-like ancestors mainly because of Darwinian natural selection?

These are the questions Pew should be answering, but it doesn't. On page 28 of this full report, it does ask the respondent to choose between the choices shown below:


A poll of scientists (with dubious aspects discussed above and below)

It is interesting that despite constant indoctrination to the contrary, nearly two-thirds of the public reject the claim that humans have evolved over time due to natural processes such as natural selection. It is also interesting here that about 10% of scientists do not believe that evolution occurs mainly because of natural processes such as natural selection.  The survey was made only of American Association for the Advancement of Science members, a subset of scientists more likely to be "old guard" thinkers conforming to ideological orthodoxy.  A full survey of scientists might have yielded a number greater than 10% doubting the "party line" on this topic.

Here we also have a case where there is a large chance of significant self-censorship, as the prevailing academic culture declares deviation from Darwinian orthodoxy as a taboo. The actual percentage of scientists rejecting the Darwinian explanation may be much higher than the 10% indicated in this survey, and could easily be as high as 15% or 20%. The people who responded to the Pew survey were people who responded after being  mailed a letter with the AAAS masthead, signed by the head of the AAAS.  That must have maximized the peer-pressure "fall in line with the majority" effect. A secret ballot without such a "Big Brother is watching" effect might have produced a very different result. 

But the poll still doesn't tell whether there is any consensus about natural selection as an explanation for evolution. The poll asks about “natural processes such as natural selection,” but does not tell us what percentage of scientists are satisfied with the "prevailing party line" claim that natural selection and random mutations can explain the mountainous amounts of biological complexity we observe. Is that percentage 70%? 60%? Or less than 50%? We don't know. Although we sometimes hear claims that almost all scientists believe the idea that Darwinian natural selection explains the origin of species and biological complexity, we don't have polls backing up such a claim. We don't know whether this supposed overwhelming majority is even a 50% majority.

What about fields such as neuroscience? Is it really true that an overwhelming majority of neuroscientists believe that the mind is purely a product of the brain? We don't know, because there is no institutional scientific process for voting on such a thing.

Conclusion

From the discussion above, two general conclusions may be drawn:
  1. When it is claimed that there is a scientific consensus on something, the consensus is often much weaker than is claimed, with a substantial minority rejecting the majority opinion.
  2. Although some claims of a scientific consensus are warranted, it is often claimed that most scientists agree on some topic, when there is actually no clear evidence that such a majority of opinion exists.
Consider also this confusing fact: you may be inclined to believe something if you hear "there is an overwhelming scientific consensus in favor of this," but you may well suspend judgment about such a thing if you hear that "a substantial minority of scientists disagree with the claim."  But both phrases can be used to describe a situation where 90 percent of scientists accept some doctrine, and 10 percent of scientists disagree with that doctrine.

So what are you going to do, when the waters are so muddied in regard to what scientists think? The answer is simple: decide based on facts, logic and evidence, rather than following an “I'll think like most of them think” strategy. Since the insular tribes of academia are often ideological enclaves very much subject to dubious thought customs, inappropriate hero worship, bandwagon effects, sociological influences and groupthink, it's not a good idea to simply follow an “I'll go with the crowd” principle. “Follow the facts” and "follow the logic" are better principles than “follow the crowd.”

Thursday, June 29, 2017

Why Did They Call These Tiny-Brain Hominids “Almost Human”?

A recent book on paleontology is the book Almost Human: The Astonishing Tale of Homo naledi and the Discovery That Changed Our Human Story. The book is by two paleontologists named Lee Berger and John Hawks. They and their colleagues found some fossils of a species called Homo naledi.

So how does that fit into some scheme of human origins? On page 42 of the book, the authors have a diagram entitled, “A Depiction of the Family Tree of Hominin Species.” It's a quite wobbly-looking diagram, not something that should cause anyone to think that our scientists have human origins figured out very well. This is because the diagram is one of those “tree of ancestry” types of diagrams, but four of the nodes in the diagram are question marks.

The diagram makes these claims:

  • From Unknown Ancestor 1 there descended Paranthropus boisei, Paranthropus robustus, Austrolopithecus africanus, Austrolopithecus afarensis, and Unknown Ancestor 2.
  • From Unknown Ancestor 2 there descended Homo rudolfensis, Australopithecus sediba, Homo habilis, and Unknown Ancestor 3.
  • From Unknown Ancestor 3 there descended Homo erectus, Homo floresiensis, Homo naledi, and Unknown Ancestor 4.
  • From Unknown Ancestor 4 there descended modern humans, Neanderthals, and archaic African humans. 
     
So according to the diagram, there is not just one missing link, but four missing links. When you look at the diagram, it seems to have  quite a bit of arbitrary guesswork. If you do a Google image search for “Hominin family tree,” you will see other diagrams, some of which give a different story. The ancestry tree in an article at Britannica.com has even more question marks, having a total of 7 question marks, indicating seven missing links.

Credit: Britannica.com


The diagram in the Almost Human book puts Homo floresiensis in the left top of the “tree of ancestry,” claiming Homo floresiensis was close to being an offshoot of Homo erectus. A recent study rejects this positioning, claiming that Homo floresiensis has a completely different ancestry, and was an offshoot not of Homo erectus but Homo habilis. Given such a confusing hominid fossil record, with a large variety of different skulls found at different places around the world, it is no wonder that paleontologists often disagree with each other in drawing a tree of human ancestry.

Part of the uncertainty is because our paleontologists do not have what they would like to have. This is one of the dirty little secrets of modern evolutionary biology. Our evolutionary biologists do not have the DNA evidence they need to solidify the claims they make about human origins. The problem is that regular organic material rots in less than a few thousand years, and you can't get much DNA from a very old fossil bone. It has been estimated that the half-life of DNA is only about 500 years. So we don't have any adequate DNA evidence from Homo erectus or Homo habilis, which are claimed to be ancestors or evolutionary cousins of the human species. The oldest DNA from a claimed human ancestor is a scrap of DNA dating back 400,000 years. But this is only about 16,000 base pairs, and the human genome is 3.2 billion base pairs. Such a tiny scrap doesn't give you a hundredth of what you would need to genetically verify that such an organism was an ancestor of humans.

Imagine a trial in which the prosecution claimed that blood photographed at a crime scene is the blood of the person being tried. But imagine the blood was washed away by a thunderstorm before its DNA was checked, so no DNA match was made. That's the kind of position our evolutionary biologist is in. He really needs some complete Homo erectus DNA or Homo habilis DNA to back up his claims that these are human ancestors or human evolutionary cousins. But no such DNA exists, merely a rare scrap here and there.

We do have the complete DNA of modern humans and modern chimpanzees, and some argue that the similarity between these two implies that both had a common evolutionary ancestor. It is claimed that the protein-coding part of the human genome is 96% similar to the protein-coding part of the chimpanzee genome. But this refers to merely the building materials of proteins (amino acids), and is not based on a comparison of the full proteins, each of which has a 3D shape. No one knows for sure how proteins get their 3D shapes. This is the long-standing protein folding problem discussed here. When you look at the full proteins including their shapes, not just the amino acid building blocks specified in DNA, it turns out that chimpanzees and humans are not so similar. The scientific paper here is entitled “Eighty percent of proteins are different between humans and chimpanzees.”

Does the fact that hominid fossils can be arranged into a “tree of ancestry” diagram prove that they have an evolutionary relationship? Not really. Given any large random data set, and a person determined to show some “tree of ancestry,” it is usually possible for a “tree of ancestry” to be created. For example, if I go into the Yankee Stadium parking lot, and diligently start looking for cars that look like descendants of each other, I would be able to cherry-pick some cars and arrange them into a “tree of ancestry” showing what might look like a plausible evolutionary progression from one car model to another. But such a diagram (looking rather like the one below) would probably not be historically correct. 


But what about the fossils that Berger and Hawks found, the Homo naledi fossils? Are they, in fact, fossils of some species that was “almost human,” as the book title states? Not by a long shot. On page 193 of their book, the scientists finally give us an estimate of the brain size for the Homo naledi organisms corresponding to the fossils they found. It was about 560 cubic centimeters for a male, and about 450 cubic centimeters for a female. The average size of a male human brain is about 1350 cubic centimeters.

So far from being “almost human,” Homo naledi had a brain only about 41% of the size of the modern human brain. Which means that Homo naledi was apparently well short of being even half-human. So given that our paleontologists have written a book with the title Almost Human: The Astonishing Tale of Homo naledi and the Discovery That Changed Our Human Story, we must ask: why did they choose to call their book “Almost Human”? Is it because such a title would sell more copies than an accurate title such as “Not Even Half Human”?

Sunday, June 25, 2017

Physicists Should Have Invested in Super Heroes Rather Than Supersymmetry

A recent article in the New York Times discusses the failure of attempts to find evidence for the physics theory called supersymmetry.

These are difficult times for the theorists,” Gian Giudice, the head of CERN’s theory department, said. “Our hopes seem to have been shattered. We have not found what we wanted.” What the world’s physicists have wanted for almost 30 years is any sign of phenomena called supersymmetry, which has hovered just out of reach like a golden apple, a promise of a hidden mathematical beauty at the core of reality.

The Standard Model of physics has fewer than 30 independent parameters. But according to one scientific web site, supersymmetry has more than 100 independent parameters. According to another page at the same web site, more than 10,000 scientific papers “reference” the theory of supersymmetry.

With all that work by physicists, you would think that there must be some evidence for supersymmetry. But efforts to find evidence for the theory have been a complete failure. The Large Hadron Collider has completely failed to support the theory.

Why have physicists spent so much time on such a theory? It was to try to explain a case in which nature seemed to be extraordinarily fine-tuned. The wikipedia article on supersymmetry states the following:

In the Standard Model, the electroweak scale receives enormous Planck-scale quantum corrections. The observed hierarchy between the electroweak scale and the Planck scale must be achieved with extraordinary fine tuning. In a supersymmetric theory, on the other hand, Planck-scale quantum corrections cancel between partners and superpartners (owing to a minus sign associated with fermionic loops). The hierarchy between the electroweak scale and the Planck scale is achieved in a natural manner, without miraculous fine-tuning.

The “miraculous fine-tuning” being talked about here (what is known as the hierarchy problem) is a kind of matching of two unrelated numbers so that they end up canceling each other out – rather like what you might have if you had to pay on Friday a $5000 payment to save your house from foreclosure, and you coincidentally won $5000 in the lottery on Friday morning.

But this hierarchy problem is actually much more of a coincidence. Because according to this scientific web site, “one has to hypothesize that the several correction terms cancel out to a part in 1034 (a hundred billionths of a billionth of a billionth of a billionth), if one is to make the Higgs mass smaller than a lead brick.” So maybe our analogy should be that you own 6 houses that are each behind $5000 on the mortgage, with Friday being the last day for you to save them; and you coincidentally on Friday morning buy 6 different lottery tickets that each win $5000. That's the kind of fine-tuning that seems to be involved in the case of the hierarchy problem.

Supersymmetry (also known as SUSY) is an attempt to explain away this “miraculous fine-tuning.” But supersymmetry has always been a ridiculously ornate contrivance. For example, it imagines that almost every known type of particle has a corresponding “superpartner.” It would be quite the fantastic coincidence if nature was set up in such a way. So supersymmetry is basically a kind of gigantic case of “robbing Peter to pay Paul.” It tries to get rid of one fine-tuned coincidence (the hierarchy problem) by introducing a whole bunch of other fine-tuned coincidences, involving all these cases in which a known type of particle happens to have a matching “superpartner” particle.

It's kind of the same approach taken by a similar theory, the theory of cosmic inflation or exponential expansion. That theory tries to get rid of a case of extreme fine-tuning in the universe's first second, but it does it by making assertions that require their own fine-tuning in numerous ways. So it's just robbing Peter to pay Paul. There is no real net reduction in the amount of fine-tuning required.

For years scientists were hoping that the Large Hadron Collider would produce some evidence for supersymmetry. But no evidence has been produced. The chance of supersymmetry being confirmed in our lifetimes now seems almost zero. That's no surprise. Supersymmetry is a case of trying to explain away an example of cosmic fine-tuning, and there has never been a confirmed success in any effort to explain away any case of cosmic fine-tuning. The cosmic inflation theory (the theory of exponential expansion in the universe's first second) has been sociologically successful, a case of a thought virus that spread widely. But it has not been scientifically successful, because no evidence has been produced for it (and there are many problems with the theory).

Rather than investing so much time and effort on supersymmetry, physicists would have got a lot better return if they had invested instead in super heroes. There are several ways physicists could have done that. The first way would have been to invest in physics technologies that might have given us high-tech gadgets that would allow someone to have the equivalent of a comic super-power. Physicists might have invented some fancy gadget that would give some of the powers of Batman's utility belt. Or they might have invested in some bullet-stopping force field that might have worked kind of like Wonder Woman's bracelets. Or physicists might have invested in some super-strong material that would give someone some of the powers of Spider Man or Iron Man.

Or, physicists could simply have invested in super heroes without doing any research. They could have taken all that money wasted on supersymmetry papers, and invested the money by either buying super hero comic books, or investing in companies such as Marvel that published comic books. Comic books have long been collector's items, and a comic book which sold for 12 cents back in the 1960's may sell for hundreds of dollars today. Disney paid 4 billion dollars for Marvel Entertainment. If physicists had invested in super hero comic books or the companies that published them, the physicists could have made gigantic returns for themselves or for the colleges or universities where they work. 

supersymmetry

I must confess that I myself am guilty of failing to see how much money could be made from comic books and from another collector's item: baseball cards. When I lived in a dull Maryland suburb in the early 1960's, I had lots of comic books and many baseball cards. In the suburb I lived, elementary school students were preoccupied with baseball cards. The kids would gamble the cards in various ways, which made a fun pastime. One game worked like this: you would take your stack of cards, and face your friend who also had a stack of cards. After each of you shuffled your stack, both of you would deal them into a common stack. First you would deal a card, then your friend. If your friend dealt a card with one top color bar, and you then dealt a card on top of that stack with the same color bar, you would win the entire stack that had been dealt.

In my suburb it seemed every family with boys had a cardboard box of baseball cards. But when I was eleven I moved to a very different environment: the more sophisticated locale of Washington D.C. Of course, I packed my comic books and baseball cards, and I hoped the kids there would be as interested in these as the kids in my Maryland suburb. But it seemed that none of the Washington children had the slightest interest in baseball cards. And they didn't seem too interested in comic books. I kind of thought to myself: I guess the city kids are too sophisticated for these things – maybe they're just silly suburb things. So not very long after moving to Washington D.C, I threw away all my baseball cards and comic books. What a mistake! I could have made thousands if I had kept them.

Whether children at a particular school gamble with baseball cards is a sociological consideration, a vogue of a particular locale. When groundless theories such as supersymmetry become all the rage among little academic tribes, it seems to be also a sociological consideration, a case of some vogue that went viral when it shouldn't have.

Wednesday, June 21, 2017

Shermer's Faulty Case Against an Afterlife

Scientific American columnist Michael Shermer has a new column entitled “Why the 'You' in an Afterlife Wouldn't Really Be You.” Arguing against both spiritual concepts of an afterlife and technological concepts of a “digital afterlife,” Shermer attempts to give three arguments against the possibility of an afterlife.

His first argument is without merit, as it depends on an unproven assumption. Shermer argues:

First, there is the assumption that our identity is located in our memories, which are presumed to be permanently recorded in the brain: if they could be copied and pasted into a computer or duplicated and implanted into a resurrected body or soul, we would be restored. But that is not how memory works. Memory is not like a DVR that can play back the past on a screen in your mind. Memory is a continually edited and fluid process that utterly depends on the neurons in your brain being functional.

This argument is not valid against any of these three ideas of an afterlife: (1) the idea that you have some immaterial soul that will survive death in a kind of natural way, without any divine intervention required; (2) the Christian idea that the dead will be physically resurrected by some divine agent; (3) the idea that minds may be uploaded into computers in the future, providing people with a digital afterlife. The first of these ideas does not depend on the idea that memories are permanently recorded in the brain. A person believing in a soul may believe that memories are stored largely in some soul, and may deny the claim that memory depends on neurons (a claim scientists haven't proven). The argument also does not debunk the idea of a physical resurrection of the dead. In such a case the neurons of individuals would presumably be recreated. The argument also does not debunk the idea of uploading minds into a computer. If our memories now depend on neurons (and there are reasons for doubting that), that is merely a current dependence, that could in theory be overcome if some new type of computer could be created that could store the equivalent of human neural states.

In his second argument, Shermer attempts to stretch out one of the arguments made against mind uploading, and turn that into an argument against believing in any type of afterlife. Mind uploading is the idea that in the future it will be possible for people to transfer their consciousness into a computer. The idea is that we will be able to scan the human brain, and somehow figure out some neural pattern or synaptic pattern that uniquely identifies an individual. Then, it is argued, it will be possible to recreate this pattern in some super-computer. It is claimed that this could be a method of getting a digital afterlife. Some futurists claim that if someone were to have his brain scanned and then have his neural patterns transferred to a computer, that person could discard his body, and continue to live on indefinitely within a computer.

Here is how Shermer presents his second argument:

Second, there is the supposition that copying your brain's connectome—the diagram of its neural connections—uploading it into a computer (as some scientists suggest) or resurrecting your physical self in an afterlife (as many religions envision) will result in you waking up as if from a long sleep either in a lab or in heaven. But a copy of your memories, your mind or even your soul is not you. It is a copy of you, no different than a twin, and no twin looks at his or her sibling and thinks, “There I am.” Neither duplication nor resurrection can instantiate you in another plane of existence.

Minus the clumsy twin reference, this argument has considerable force against the idea of a digital afterlife through mind uploading. If I were to scan your brain and recreate your neural pattern inside a computer, that seems to be making a copy of your consciousness rather than a transfer of your consciousness, for two different reasons. The first reason is that a transfer has been made to a totally different medium (from a biological platform to an electronic platform). The second is that the mind upload seems to leave open the possibility of your biological body continuing after your mind upload has completed, and that would seem to be the creation of a copy of your consciousness rather than a transfer.

But the copying argument has much less force (and perhaps no force) when used against the idea of a physical resurrection of the dead. In that hypothetical possibility, there is no transfer to a different medium. A physically resurrected body would be the same (or mostly the same) as the body that existed before someone died. Also, a physical resurrection would presumably only occur for people who had already died. So there would be no issue that both a source and a target (or copy) could exist at the same time.

The copying argument has no force at all against the idea of a soul that continues to exist after a person's body dies. In such a case, presumably there would be no copy at all made of anything. A person who believes that the soul survives death does not tend to believe that the soul suddenly appears at the moment of death, suddenly having a copy of consciousness and memory that was stored in the brain. Such a person will instead tend to believe that the soul was a crucial component of the human mind all along (or perhaps was equivalent to the mind), and that such a soul simply continues to exist when a person dies.

Imagine a person who has worn a heavy lead coat all his life, and has worn a dark glass fishbowl over his head all his life. Under the soul concept, we may regard death as being rather like a person shedding that heavy lead coat and dark-glass fishbowl, with the heavy lead coat and dark-glass fishbowl being the restrictions of movement and perception associated with a human bodily existence. Under such a concept, there is no copying at all, but more like a kind of jettisoning, rather like a soaring rocket jettisoning a no-longer-needed fuel tank, with the body being what is jettisoned. Such a concept of the survival of the soul is completely free from difficulties involving copying, because no copying at all is assumed.

Shermer's third argument has no force against any concept of an afterlife other than a digital afterlife. Using the odd term “POVself,” he argues as follows:

If you died, there is no known mechanism by which your POVself would be transported from your brain into a computer (or a resurrected body). A POV depends entirely on the continuity of self from one moment to the next, even if that continuity is broken by sleep or anesthesia. Death is a permanent break in continuity, and your personal POV cannot be moved from your brain into some other medium, here or in the hereafter.

Such reasoning based on continuity might have some force against the concept of a digital afterlife by means of mind uploading, but probably not very much force as Shermer has stated it. For he's used the phrase “there is no known mechanism,” which is hardly going to discourage futurists who will claim that such a mechanism will be invented in the future. The reasoning here also has no force against either the possibility of a physical resurrection of the dead or the idea of a soul surviving death. A Christian believing that the dead will be physically resurrected will believe that this is done through divine agency, so it is futile to argue that such a thing cannot occur because there is “no known mechanism” by which it would occur. The person believing in a soul that survives death need not believe that any transfer, copying or moving occurs to allow a person to survive death. Such a person will tend to believe that the essence of a person – what makes you you – has already resided in your soul all along, not in your brain; and such a person is not required to believe that anything is transferred from the brain to the soul when a person is died. Under the idea of a soul, there is no break in continuity when a person survives death.

Neuroscientists have always followed the principle: explain every conceivable mental activity as being something caused by the brain. But what we must remember is that Nature never told us that all our memories are stored in brains, or that our thoughts are generated by brains. It was neuroscientists who told us that, not Nature. For example, we have no understanding of how 50-year-old memories can be stored in brains, given all the rapid molecular turnover that occurs in brains. Below is a quote from a recent scientific press release, citing a comment by a neuroscientist.

Neuroscience has also been struggling to find where the brain stores its memories. “They may be ‘hiding’ in high-dimensional cavities,” Markram speculates.

Such a quote (which has a “grasping at straws” sound to it) gives a very strong impression that neuroscientists have no real basis for being confident claiming that long-term memories are stored in the brain. The type of evidence neuroscientists cite for their claims is often weak evidence that doesn't hold up to critical scrutiny, such as dubious brain scanning studies which typically take minor 1% differences in brain activity, and try to make them look like compelling signs of what the brain is doing, when they are no such thing.

The idea behind a soul or spirit can be summarized as follows. You have a soul or spirit that is not at all a brain thing. You also have a brain, which serves largely for the purpose of localizing or constricting your mental activity, making sure that it stays chained to your body. The main purposes of the brain are things like control of autonomic functions, response to tactile stimuli, coordination of muscle movement, the coordination of speech, and the handling of sensory and auditory stimuli. There may also be some brain function relating to storing kind of what we may call “muscle memories,” which we use for performing particular physical tasks. These are all things related to living and surviving as a corporeal being. But things such as abstract thinking, conceptual memory and long term memory may be functions of a human soul. So when you die you may lose those things that you needed to continue walking about as a fleshly being, but may still have (as part of your soul) those things that were never necessary for such an existence (no cave-man needed to form abstract ideas, think philosophical thoughts, or remember his experiences as an 8-year-old).

This idea may seem old-fashioned to some, but a strong argument can be made that it is compelled by fairly recent evidence, and that in such a sense it is not at all old-fashioned. It is only in recent years that we have discovered what a very high degree of molecular turnover occurs in the brain, which makes it so hard to maintain that 50-year old memories are stored in the brain, as discussed here. It is only in the past 50 years that we had research such as John Lorber's, showing astonishingly high mental functioning in patients who had large fractions of their brains (or most of their brains) destroyed by disease. It is only in the past 130 years that experimental laboratory evidence has been repeatedly produced for phenomena such as ESP, which cannot be accounted for as a brain effect. It is only in recent decades that we have had reports of near-death experiences, in which many observers have reported floating out of their bodies, often verifying details of their medical resuscitation attempts that they should have been unable to observe  while they were unconscious. Such observations are quite compatible with the idea of a soul that survives death, and may force such a conclusion on us.

Shermer seems rather to be thinking of the idea of the soul as something kind of like a USB flash drive to back up the brain. But those who have postulated a soul have more often supposed it as a crucial component of human mental functioning, not some optional accessory. Under the concept of a soul that accounts for a large fraction or most of human mental functioning, there is no requirement for any sudden copying from the brain to occur for someone to survive death; and there is also continuity, as death merely means discarding what you don't need to survive beyond death. As none of Shermer's three arguments damages such a concept, Shermer has not succeeded in closing the door to an afterlife.

We know not what lies at the end of the misty bridge