Outer Limits of Reason (52 page)

The answers to Wigner's unreasonable effectiveness lead to much deeper questions. Rather than asking why the laws of physics follow mathematics, ask why there are any laws at all. Why these laws and not other laws? Why is it that what we learned by looking at different marbles is also true about many other physical phenomena? Why do the planets follow the shape of an ellipse, or any other repeating shape for that matter? Why not a square or a circle? These deep—and perhaps unanswerable—questions are the central topic of the next section.

8.3  The Origin of Reason

Imagine driving along a highway late at night and deciding to stop at a hotel to get some shut-eye. You choose one of the many indistinguishable large hotels on the side of the road and ask for a room. The hotel is mostly empty and the manager gives you a randomly chosen room. You sleepily enter your room and to your surprise you find the closet and all the drawers are full of clothes. There are shoes, slippers, and a robe. Shockingly all the clothes are exactly your size and taste. The slippers are worn out just the way you like them. The shoes are an exact fit, both in style and size. The robe is exactly the material and color you like. How could this be? From all the hotels and all the rooms in the hotel, why does this one have everything perfectly made for you? This sounds like the beginning of a suspenseful movie thriller.

Let's imagine some scenarios that could explain these strange coincidences. It could just be a fluke. It happens to be that the person who was in the room right before you was the exact same size as you and the maid did not properly clean out the room. You simply found that person's leftover stuff. Had you chosen any other room, had any other person been in the room before, or if there had been a slightly more competent chambermaid, you would have found either different clothes or a cleaner room. What are the odds? Nothing like this ever happened to you before. This is a rather an improbable fluke.

It could be that a bunch of crazy marketing executives have decided to make everyone's hotel experience more “homey.” After much nonsensical research they decided to leave “typical” clothes and stuff in every room. It just so happens that you are the exact size and your style is exactly the same as the “typical” person. One can easily check this nutty theory by looking into other rooms and seeing whether they also have the same stuff there. Alas, you cannot get into the other rooms to check. Yet another possibility is that the hotel managers have decided to make every room homey with different style and size clothes. Either by luck or on purpose your room fits you. Again, a peek into other rooms will show whether this is true or false.

If you wanted to get all conspiratorial, you can say that there is a vast network of alphabetical intelligence organizations like the CIA, KGB, and NSA that have been following you around with black helicopters and satellites. When they saw that you were going into a particular hotel, they turned on their omnipresent listening devices to find which room is yours. Or perhaps the pleasant person behind the counter of the hotel is “in on it.” Once they knew what room you were going to, they put in all the different clothes right before you entered. What these nefarious agencies want from you is still not exactly clear . . . but . . . I would get out of that room quickly.

Of course, this fun little excursion into moviedom is not real. But there is a question in science that is similar to this strange scenario and is very real. For reasons that are not very clear, the universe is shockingly well suited for rational human beings. The laws of physics seem to have been designed so that complicated beings with the ability to reason could exist. Why should this be?

The laws of physics could have been different and yet they are not. What would happen if they were slightly different?

• If gravity were stronger, then stars would collapse into black holes more quickly than they do. Stars are mostly made up of hydrogen and helium. In a process called
stellar nucleosynthesis,
heavier elements such as carbon and oxygen are formed. If gravity would collapse stars into black holes more quickly, there would be no time for these important elements to be formed. The universe would not have the complex building blocks necessary for life.

• If gravity were weaker, then stars and planets would not be held together and nucleosynthesis would not take place. Again, there would be no building blocks for life.

• If the Earth were a little closer to the sun, all the water needed for life would become a gas.

• In contrast, if our orbit were a little further away from the sun, the water on our planet would freeze and again life would be impossible.

• Physicists talk about a force that works against gravity and its strength is measured by the
cosmological constant
. It is necessary that this constant have a certain value or the universe as we know it could not exist. Astrophysicists have calculated the value that the cosmological constant must have for complex living beings to exist. They have found that if the value were slightly different, we would not be here to worry about it. The value is calculated to the 120th decimal place. It seems our universe is perfectly suited for us.

• If the average IQ of human beings were ten points lower, where would the human race be? Would we have been able to place someone on the moon? Would we be able to make and use the computers and other machines that are so much a part of our lives? If the average IQ were thirty points lower, would we be able to ask these questions about why the universe is the way it is?

This list can go on forever. The universe would be radically different if these constants of nature or the laws of physics were slightly different. Life, and in particular human life, would probably not be possible if there were slight changes in the universe. Scientists call this mystery that the laws of physics are so perfectly formed the
Goldilocks enigma
or the
fine-tuned universe
. Rather than the laws being “too this” or “too that,” the laws are “just right.” They are like a fine-tuned musical instrument perfectly set to make the cacophony of intelligent human existence possible. Why are the laws just right?

There are many overlapping questions that are usually lumped together. We cannot even begin to start addressing these difficulties until we disentangle the questions. The questions can be classified into three levels, one inside another, like a Russian (matryoshka) doll:

Question 1:
  Why is there any structure at all in the universe?

Question 2:
  Why is the structure that exists capable of sustaining life?

Question 3:
  Why did this life-sustaining structure generate a creature with enough intelligence to understand the structure?

Let's consider these questions in more detail.

Question 1:  Why is there any structure at all in the universe?

Why are there laws of nature? Why should there be any regularity in the way physical objects interact? The actions of the physical universe have a certain pattern and these patterns repeat themselves regardless of time and place. There is a certain consistency and regularity to the laws. They are applied in every way and at all times. We can perform an experiment here and on Mars and get the same results. We can perform an experiment on Sunday and Tuesday and see the same outcomes. Why should there be such a consistency and repetitiveness of the laws? Why does the universe seem so normal to us rather than as some type of psychedelic Salvador Dali–type painting? It is hard to even imagine the universe if it lacked such structure.

We can ask even deeper questions. Rather than wondering why there are laws that act on physical objects, ask why there are any physical objects at all. What if the entire universe was a vast vacuum without physical objects? And yet there are physical objects in our universe. Why should that be? We can, of course, go off the deep end and ask why there is a universe at all. There is really no reason why anything should exist. Philosophers state these types of questions with the catchy phrase, “Why is there something rather than nothing?”
⁴¹

Question 2:  Why is the structure that exists capable of sustaining life?

Given that there is a universe and there are physical objects in the universe that follow habitual laws of physics, why should there be any life in the universe? The laws of physics are set such that there is a possibility for a process we call life. In order for there to be life, the universe must have enough complicated material so that life can grow and develop. All the life forms that we know of are made out of carbon. In fact, organic chemistry, which is essentially the study of living things, is the chemistry of carbon. The vast majority of material in the universe is hydrogen and helium, which is too simple to create complicated structures. The universe must be able to convert the simple materials to complicated materials. Another requirement that the universe must have for life is time. There needs to be enough time for the complicated process of life to occur. The laws of the universe need to be very fine-tuned so that such complicated materials exist and long enough time for such a procedure to occur. We happen to live in a universe with exactly such laws. Why are the laws of physics so propitious for the development of life?

Scientists have determined that if certain physical laws were a little different, the complex materials and processes needed for any type of life could not exist. We can conceivably argue about the definitions of life (see below) and how different these laws of physics can be, but nevertheless there seems to be an amazing confluence of strangely exact laws that make life in this universe a possibility. Why should this be? We can ask a deeper question: Just because the constants and the laws of physics are just right for life, why should life still happen? Just because a pair of dice can land on snake-eyes does not mean they, in fact, will land on snake-eyes. Why
does
life exist in a universe where life
can
exist?

In contrast to the first group of questions, where it was hard to imagine the universe (or lack of one) in such a chaotic state, it is easy to imagine the world without any life. As far as we know, there does not seem to be any life outside of our little blue planet. That means, for the time being, the rest of our vast universe is as dead as a doorknob. One can easily imagine some lawyers-turned-politicians declaring global thermonuclear war with the consequence of all life on Earth—not just human life—being destroyed. This will be a lifeless universe.

Question 3:  Why did this life-sustaining structure generate a creature with enough intelligence to understand the structure?
⁴²

Given that there is a well-working universe and that there is life in this universe, why should some of that life have intelligence?
⁴³
The human brain is probably the most complicated object in the universe, and as such, is capable of some of the most amazing feats in the universe. The mind is also the only object in the known universe that wonders at the universe. Not only does it try to control the forces of nature that are around it, but it also tries to understand those forces. It is not just that we are intelligent and that we can play chess and understand some of the jokes on
The Simpsons
. Rather, we can go on and try to figure out why the universe is set up the way it is. Is it merely a coincidence that the universe spawned a creature capable of partially understanding the universe? At the present time we do not have total understanding of the universe around us. We also might never achieve total understanding of the universe, but we nevertheless understand part of it. Homo sapiens are also the only known creatures in the universe aware of their own existence. Why should this be?

When we take certain medicines or have too much tequila, our intelligence goes down. Our ability to understand or follow reason is impeded. This shows that our reasoning ability is very much a physical process, and as a physical process it is subject to the vicissitudes of the laws of nature. Why is it that our mind is so attuned to learning about nature? (Or is it? The vast majority of us would rather watch
The Simpsons
than study the laws of nature.) Slight changes in our environment make us less reasonable creatures. (What about changes that could make us into
more
reasonable creatures and
better
scientists? Would we know more about the universe then?)

Just because the universe is well suited for intelligence does not mean that the universe has to have intelligence. After all, before humans existed there was life on Earth without intelligence. Similarly, if we continue to mistreat each other and our planet, intelligent life will be destroyed and only cockroaches will remain. The universe and its perfectly formed laws will still be around even though there will be no one to study the laws or be in awe of them. There is nothing to ensure the continued existence of this fragile species.

It is not only that the laws of physics are well suited for reasonable creatures, but in a sense we learned reason from the laws of physics. As we saw in the last section, humans learned mathematics from the physical universe. Five apples added to three apples gives us eight apples, which teaches us that 5 + 3 = 8. Again, in the last section we saw the intimate relationship between the common notion of an ellipse and planetary motions. Why should there be such regularity in the universe so that ellipses that we draw on a piece of paper should also show up in the heavens? It might make sense that we understand the quantum world by looking at the tools of abstract algebra. But why should the quantum world, in fact, work with abstract algebra that we learned in other places? The physical universe also follows logical rules. For example, if you know that
A
or
B
is true and then you learn that
B
is, in fact, false, then you know that
A
is true.
⁴⁴
The very fact that we can observe such regularities with the laws of nature makes reason possible. Why do the laws of science have this perfect form? In essence, we are asking why there is any reason at all.