How Can Molecules Think?

I think with my brain. My brain is made of molecules. Therefore, molecules, when arranged in a certain way, can think.

But how can that be? After all, you are alive, and you feel what it is to be alive. You are experiencing conscious awareness. How can this awareness be nothing more than the result of molecules and elementary physical particles?

Your conscious awareness might seem to you to be something immaterial that is telling the molecules of your body what to do. And yet, as I wrote at Is There Life after Death, there is abundant evidence that the physical brain is indeed the thing that thinks. There is no soul inside running the show. The brain is in control.

Here I will discuss some ideas on how the brain might do that. I won’t give you the definitive answers. Nobody knows exactly how the brain works. We are a long way from understanding the brain’s inner workings. But we have ideas of how it could be happening. So, let’s look at some ideas of how it could all work.

Simple neuron activity

Let’s begin with simple neural function. It can be nothing more than a set of impulses that arrive from incoming nerves and connect to a set of neurons. These neurons gather the information and trigger a muscular reaction.

A simple example of this is when the doctor taps your knee, and your leg kicks forward. As the doctor taps your knee, a muscle gets stretched. Nerves sense that the muscle is stretching. Your body interprets this as a sign you could be falling, so it quickly reacts by tightening the muscle that is stretching.

Below is a simple diagram of how nerve processing can trigger simple movements. This can be as simple as a programmed reaction to a tap on the knee, or it can be much more complex and control multiple muscles. For instance, a group of neurons could be wired to produce simple walking movements whenever something is sensed. When walking is desired, the neurons could move a leg forward if it happens to be in a raised position; to move the leg down whenever it is forward; to move the leg backward whenever it is down; and to move the leg up whenever it is back. The result would be a leg that automatically goes through a walking movement, pushing the animal forward.

This walking motion can be made more complex by wiring multiple sensors and several legs to the same set of neurons. The neurons could then produce coordinated movements, such that one or more legs raise and move forward while other legs are on the ground pushing backwards, thus pushing the animal forward.

If the triggering sensors were simple light detectors, for instance, then the animal would move forward whenever it sees light.

If there is a light senor on each side of the body, with each sensor causing legs on the opposite side to move faster when that sensor saw bright light, the animal would move the side facing darkness faster than the side facing light. This would tend to turn the animal to face the light as it moved forward. Thus, simple wiring of the neurons could direct an animal to always face the sun and move forward.

Software controlled movements

Let’s look at something a little more complex. The diagram below adds in memory and a sensing of the physical state of the animal.

In its memory, this animal could store memories of past movements, and recall those movements the next time it needs to move. Thus, the animal can learn from experience. It does not need to have the exact leg movements precisely hardwired. Rather it can recall previous movements that were successful and repeat them. It can modify the movements with time as necessary.

How does it know which movements were successful? This is where knowledge of the physical state could come in. If in the past an animal had made movements that allowed it to quickly reach its prey, thus resulting in a satisfied mental state, those specific movements could be saved in its memory. The nerves would record that when this animal runs with certain movements under certain conditions, it is more likely to catch food. The neurons would remember to do that again.

Supervisory Control

Knowledge of the physical state can fine tune how the animal uses its senses. For instance, if a certain combination of signals from a complex eye is typical of a tasty meal, then the animal with memory can record that this is what food looks like. It can remember that when it saw something like this in the past, it moved forward, ate, and experienced a state of satisfaction. So, it can know to do that again.

Here is a block diagram of a more complex mind. Neurons can evaluate the information from the senses and issue commands. Other neurons can read these commands and determine how best to move the muscles to reach the desired goals.

The blocks above do not represent distinct parts of the brain. Rather, the activity described is shared throughout the brain. The blocks are just concepts to help us understand things that might be going on. It is certainly more complicated than this, and probably doesn’t happen just as shown. But processes like this must certainly be happening in animals.

And surely these animals do not all have souls. Insects, worms, and lizards move based on activity occurring in neurons. Surely, you must agree that insects do not have souls. Instead, they must be moving based on simple physical neuron activity. So, the movements of the ant’s legs are indeed driven by molecular thoughts similar to the process described above. Molecules can and do think in this sense.

Likewise, although you may think humans have souls, you must surely agree that much of what is described above is being done inside the physical brains of humans, rather than in a separate soul. Surely the soul is not deciding how to coordinate the various muscles when you are running. You just run. Unless you have reason to study the muscles involved, you have no idea what exact movements need to be made each step of the way. You just decide to run, and the brain takes over from there, and controls the legs. Your soul, if it exists, simply issues the supervisory command to run, and the brain takes over from there.

If we decide that some parts of thinking are done in the brain, and other parts done in the soul, how do we determine which actions are done by the soul? Does the soul control the breathing muscles? What about the legs muscles when running? Or your hands as you swing a bat? Or your foot as you hit the brake when an animal runs in front of the car? Or the sudden curse word when you hit your finger with a hammer? Or the angry words when another driver cuts you off? If the soul is distinct from the brain, there is no clear break as to where the soul stops, and the brain starts.

The Bible says we will give account for every careless word we speak, so that seems to indicate the quick “damn!” that comes out when you stub your toe came from the soul. But is that reaction distinctly different from the muscle movements that moved your foot forward? Could it be that both are simply the result of neurons acting?

I contend that there is no soul. It is all brain. After all, the brain can control many movements in animals that have no human souls. Why cannot your brain be doing the same for you? And why can it not be doing even the more complex things that humans do?

Speech

Ah, but human speech is quite complex. How can that be driven by neurons?

We do know neurons can control elementary speech in animals such as dolphins. And gorillas such as Koko have used sign language in ways that have similarities to human speech. So yes, it is certainly conceivable that neurons can generate human speech.

Suppose you are sitting at the table eating dinner. Suddenly the words come out of your mouth, “Please pass the biscuits”. Where did those words come from? Even after you knew you wanted somebody to pass the biscuits, it took enormous computing power to create that sentence. Somehow you had to look at the available English words and the laws of English grammar and put together that sentence. But you are not aware of all the possible words you considered. You don’t remember looking up the definitions of “pass” or “biscuits”. You could have used other words. But somehow the words you needed just filtered themselves out, came to the forefront, formed themselves into a sentence, and you spoke.

Forming sentences is an incredibly complex activity. Computers that interact in conversational English rely heavily on prefabricated sentences, and yet they still require enormously complex programs to build anything resembling human dialog. Google’s LaMBDA chatbox, for instance, required a huge programming effort. It needs to analyze words that might be appropriate in any situation, and somehow fit them together to make responses. And yet even this is far short of the human capacity to create sentences. (And no, the LaMBDA chatbox is not conscious.)

So, when you asked for the biscuits, how did all that data get processed to make your sentence? When you screamed at the person who cut you off on the highway, or responded to a question from a stranger, how did that sentence get formed? Whether you believe in a soul or simply that the brain is in control, somehow there is a mystery of how this data all got processed. Somewhere outside of your direct control that sentence was formed for you. How was that done?

I contend that there were thousands of neurons in your brain all working together to figure out what to say. And they drove your speech.

The diagram below indicates how this might happen. You are aware of what the incoming data is sensing–those biscuits look delicious. And you are aware of your state: You are eating with others, and you are hungry for another biscuit. But you are also aware of many other things you may want to say, such as telling a joke, telling a story, or talking about the meal. Surely, there are many things you could have said next. But somehow the thought to ask for biscuits came to the foreground. How did that get there?

In the diagram above, I show that your mind selects the concepts that you wish to express. Multiple parallel processes were going on in that central processing, but one concept came to the forefront, to ask for biscuits. And immediately, as you decided to ask for biscuits, multiple parallel processes must have engaged to decide how best to word that request. Somehow something somewhere looked up the words you know in your native language, your knowledge of grammar, and the physical reality around you, and it picked out an appropriate sentence. That sentence arrived in your conscious mind, fully formed.

And then you spoke, but again there must have been enormous data processing to control your vocal cords, tongue and lips exactly as needed to express the chosen words. But you are aware of none of those decisions to drive your muscles. They just happened.

Ah, but you will tell me you were still in control. You had the opportunity to evaluate the sentence that was presented to you. And you could have decided it needed to be asked as a question or needed to mention the person’s name. But exactly what is that “you” that was doing that deciding? For, as we saw elsewhere, science indicates that the brainwaves associated with such decisions precede the knowledge that you are deciding. So perhaps the “you” that was deciding was the brainwaves that make up your mind, not some self-aware part of you that observed it all.

If you decide to address a person by name, then something somehow looked through all the database of faces and decided what name applies to the face of the person in front of the biscuits. Again, there was enormous data manipulation to determine that the person in front of the biscuits was Aunt Mary. Computers require complex programming to be able to duplicate that facial recognition. But somehow something figured out that it is Aunt Mary. You don’t know how that happened. It just happened. And “you” immediately approve of the revised request that comes to you and you speak, “Aunt Mary, would you please pass the biscuits?”

Self-Awareness

Notice that we just slipped something new into the discussion: “you”. Somehow there is something that I refer to as “you”–and you refer to as “me”– that is a self-aware entity. Where did that come from? I contend that the thinking process itself created that self-awareness. The neurons in your brain created that “you”.

How can a brain do that? Below is a model of how the brain might think, based on an analysis found here.

In this model, your senses and physical state are constantly feeding information to your internal processing. The internal processing sorts it all out, comparing all the inputs with previous inputs. For instance, it determines that the face over there is that of Aunt Mary, and the things in the plate in front of her are biscuits. And that you are hungry for biscuits.

Your mind then starts putting it all together. It evaluates your current state. You are hungry; you also want to tell a certain story; you also have things you want to do after dinner; and, oh yes, you also need to release gas. Simultaneously, processes in your brain are setting goals. You want to have more biscuits; you are just itching to tell that story; and you would feel a lot better if you asked to be excused to go to the bathroom. All these goals and all these state evaluations bubble into a state comparison function. The largest differences between your goals and your current state build into a charge structure that amplifies whatever is the biggest current need.

Whatever idea wins at any given moment comes to attention. With that thought at attention, it is able to issue commands to your body to do what it deems necessary. Does the thought at attention say you need to ask for biscuits? You ask for biscuits. Simultaneously similar processes determine what words to use and how to move your muscles to create those words.

But simultaneously other things are bubbling in through the charge structure, trying to bring to your attention the need to eat another bite of food from your plate, for instance, or the need to wipe your mouth, or the need to look at somebody that is talking. All those thoughts can come to consciousness as they build up sufficient collaborating neurons to put that thought in the foreground.

That stream of ideas that come to attention and control your body is important to know. If, for instance, you are telling a story, then it is important that the whole of your mind understands that you are in the process of telling this story which you find important. There simply cannot be any continuity to who you are unless somehow the stream of your thoughts at attention are recorded and fed back to the rest of your mind. The internal processing that is reading your physical state and your senses needs to know what is actively at your attention and driving your current movements.

So, you mind includes an important feedback mechanism. The brain creates a self-awareness. It looks at the stream of thoughts coming to attention and constantly saves that off as a memory of what you are currently doing and have been doing.

Experiments show that our brains are firing to drive the decisions before this self-awareness is aware that we are deciding this (as I discuss here). So, the self-awareness is not in charge. It is simply the brain making a story of a person in charge that is running the show.

Your brain needs this story. Complex language requires that we are aware of the words we have recently said and the intentions of the brain when it said those words. Other complex activities like stalking prey need similar awareness. And so, the brain makes up the story of a self-aware person in charge that is driving these decisions. As this simulated self-aware being is fed back to the rest of the brain, the brain drives future decisions based on what was previously decided.

This self-awareness needs to be limited in scope. For your brain could not possibly record the state of every single neuron, and it certainly could not record the state that every neuron was in at every moment last week.

But a complete knowledge of the entire brain is not needed. All we need is a summary of those ideas that came to the forefront and drove our speech and bodily movements. So, our body saves off a condensed summary of what we have been paying attention to.

That self-memory is constantly being rewritten. We need to know in detail what happened in the last 5 seconds. But we don’t need to save that memory forever. As time goes on, we can rewrite that memory of the last 5 seconds as part of the story of what happened in the last 5 minutes, the last 5 hours, the last 5 days, the last 5 months, the last 5 years, and the last 5 decades. Each time the story gets summarized and condensed, the details can change. Unimportant things can be dropped. The memory of what happened 5 years ago won’t exactly correspond with what happened. But it is good enough to get us through life. Our minds build a story of who we are and what we have been doing, a story that runs right up to an interval just a split second ago.

That stream of memory seems to me to be synonymous with consciousness. It is the recorded story of who we are. The story gets written such that it says the consciousness is in charge, but that is not really the case. The physical components of the brain are in charge.

So yes, it may seem to you that there is something immaterial in charge that can evaluate all the possible responses presented to it and choose which action to perform. But the self you are observing could be nothing more than the summary that is being written by your brain.

Your brain may find it necessary to record that you debated several different ways to ask for the biscuits, but all it is doing is recording the various options that were presented through your charge structure to your attention. You are not recording how those ideas got into the charge structure and bubbled up to the top.

Life goes on. Your brain constantly gets inputs and looks at its memories. It allows multiple parallel processes to compete for attention, with the stream that wins out getting saved off as the conscious decider. But this consciousness is not really in charge.

And yet being alive seems so real. How is it that consciousness seems so real to us? This is sometimes referred to as the hard problem of consciousness. There are no easy answers. It all seems so real, but science indicates our consciousness is indeed created by our physical brains.

You may think a soul explains this all better. But appealing to a soul is little more than an appeal to magic. How, for instance, can souls store memories? Surely, if a memory is stored, the state of the soul must be different after the memory was stored from the state it was in before it stored that memory. But how could souls with no material components change and store this fact? Computers and brains do it by a change in state of the constituent matter. How would souls do it? There would be nothing there to store that memory. So, even if we didn’t have all the evidence showing it is the brain that thinks, we would still find that appealing to a soul does little to solve the hard problem of consciousness.

In summary, we have looked at models of how physical brains could form our thoughts and create an image of a self-aware consciousness that is driving the show. All of this could be done by physical parts of our brains, not by an immaterial soul.

Does this eliminate personal responsibility? No, you are still you, regardless of whether that self is an immaterial soul, or the sum of molecular functions. That “you”, the mind that is in control, still needs to be held accountable for what it decides. The mind that decides wrong things may need to be punished, thus discouraging that mind and other minds from doing future wrong things. We still need to treat the mind as responsible for what it decides.

I hope this discussion has helped you think about what may be going on in your brain. And I hope it helps you understand that you really can be a physical self with no soul, a self that has only this life to live. And I hope you decide to fully live this life, for this is the only life you will ever have.