A couple of weeks ago, my son told me how his friends at school started a discussion group, where participants tried to figure out all sorts of stuff. One of the topics was, what is a soul? Does it really persist after death? Are there ghosts and spirits? How does all of that work? We discussed it for a while and I explained that I think a soul seems to describe who you are, your essence. That it is related to your personality, your character, what makes you you. Your friends and colleagues expect you to respond to events in a familiar, fairly predictable way. If you don’t, it tends to shock them, as you are doing something out of character.

Regarding whether souls persist after death, I honestly don’t know how that works. What I have personally witnessed is that when a person has died, their body still retains its resemblance. However, something has changed. The lifeless body has lost some essence and does not really seem to be the same person any more.

What I find more interesting is whether your soul already exists before you are born, before you even get conceived? The genetic material that will be used for your building blocks obviously already exists partially within your parents. And once the cell is fertilised, it is alive, magically starts multiplying and carries within it a vast amount of information. An interesting question is whether this information purely consists of the genetic instructions in the DNA from both your parents and the mitochondrial DNA from your mother? There are also thousands of enzymes and other chemical building blocks performing a myriad of incredibly complicated sequences of tasks. Do these carry any information? If any of these don’t perform their job, the whole system can end in disaster and therefore has all sorts of error checking and recovery mechanisms, to try and keep everything running smoothly. But, do you only inherit this type of physical information? Why are many people scared of heights or have all sorts of other phobias, which they very well may have from birth? Are these genetic? Can you inherit memories, that warn you of lessons learned by your ancestors? What is transferred to you, while you are in your mother’s womb? Maybe even after birth? An example is that you apparently inherit your immune system from your mother’s milk.

While pondering all of this, I watched several interviews with Michael Levin, who is a biologist researching how cells communicate. How do stem cells orient themselves with respect to one another and then decide that this bunch of cells need to start building a kidney, while a different bunch start growing a bone and others form a lung? One of the big questions that they tried to solve was, how do cells figure out what will be the left and right side of the body – do they use some sort of magnetism? They have to somehow decide which side will be the left, to grow the heart in the right place. How do they know, that this is a good spot to start growing a leg? As the embryo grows bigger in size, these decisions become more and more complicated, as there are millimetres or centimetres between the positions of the various organs, spanning millions or billions of cells. Experiments showed that the cells are communicating with an electric voltage language, making some pretty complicated decisions. If one interferes with these processes and create new unforeseen situations, the cells will try and convince one another on what the best decision is, until some sort of consensus is reached on the way forward.

When living cells are removed from an adult and placed in a foreign environment, the cell can behave in some completely new behaviour, unrelated to its previous function. It seems to have a form of intelligence, allowing it to try solve problems it encounters. Michael Levin and his team seem to be making progress on slowly decrypting the voltage language that cells use to communicate. This may offer all sorts of new therapies, where cells can be electrically manipulated to change their behaviour and potentially regrow limbs or change the behaviour of cancerous cells, without traditional medicine or surgery. If this information is of interest to you, I highly suggest you search for Michael Levin on YouTube.

But back to the soul. With indications of a survival instinct and signs of some rudimentary form of intelligence, do individual cells have a soul? Or how many cells do you have to add, to suddenly bring a soul into existence? How many organs do you have to add to your body before you become you? Do animals have a soul? Does a swarm of bees have a soul? It seems to have a form of intelligence that is able to find solutions to complicated problems that no bee brain on its own is able to solve. Do plants have a soul? Do cities or companies have a soul? Does an economy have a soul? We are desperately trying to understand the rules that it follows and often helplessly await its behaviour. Do computers have a soul? A computer containing installed programs with complicated stored data seems to have its own personality, how it responds to input. Humans frequently express that their machine is moody or having a bad day, based on its unexpected or unusual behaviour. You will immediately notice that the environment is different, when you log in on someone else’s machine or use someone else’s smartphone. What does this personality consist of? Is it the hardware? Is it the software? Is it your particular hierarchy and arrangement of folders, the names you chose for your files? That you are able to find the information you are looking for among the maze? When you receive a new laptop, how much of the information on your old laptop has to be transferred before the new one gains the essence and familiarity of the old one? Or maybe the magic happens once all the same software has been installed and you can finally start falling back on your muscle memory? When you change to your familiar old desktop wallpaper? The configurations of the operating system tweaked for the keyboard shortcuts that you are accustomed to? Is this when it becomes your familiar friend again?

You may ask what the point of this whole discussion is? Who cares? Where are the commercial applications? Well, there is big money riding on these concepts. Some of the richest billionaires arguing when we will reach the singularity. When AI agents are considered to be as intelligent as humans. How would we know when AI suddenly becomes sentient and self aware? Large language models like ChatGPT, Copilot, Gemini, Grok, Claude are becoming more and more convincing, the way they are able to reason with us, understand our problems, even seem to be able to understand our frustrations, our panic when we may have lost all of our data. As AI agents are evolving and improving, they certainly do a good job simulating their understanding of human emotions. How do we know whether the AI agent starts having its own emotions? Does it ever become real? What does real mean? How do we measure that? Do we experience real emotions? Or are we also just simulations, running on the software in our brains?

While sitting in traffic on my way to work, I was considering all these questions. As a scientist/engineer/analyst we constantly practise finding models that can represent complex systems. We need such models to simulate a complex system, to try and predict its behaviour under various conditions. The question therefore naturally arises, whether one is able to model a soul? In its simplest form, a soul seems to be the someone’s expected, familiar behaviour under various conditions. The behaviour that makes you recognisable, your essence.

Many years ago, I was exposed to a functional modelling standard called IDEF0, which was developed in the 1980s by the U.S. Air Force for modelling complex systems reliably. It was later replaced by modern business process mapping techniques like BPMN, which are able to capture decisions like IF statements and are considered easier to read and understand. However, it struck me that the IDEF0 framework may be useful to try and capture the essence of an entity or system, which cannot really be captured by a set of IF statements. That would be too robotic.

IDEF0 defines a an activity or function that is performed by a mechanism or resource, with data flowing into the activity from the left, data flowing out of the activity on the right and a set of controls influencing the activity from the top.

A whole set of activities can be strung up, with the output data from one activity becoming the input or control of the next activity. The result can become a very complicated system, where activities can be broken up into sub-activities, with potential feedback loops of output flowing back into the input of some prior activity.

This framework can be used to model all sorts of systems. For a computational system, the hardware consisting of transistors, CPU, GPU, motherboard execute the software activities. Data flows in from storage like RAM, the hard drive, or maybe the attached network and affects the activity being performed. This, in turn, produces outflow data, which affects the next activity or returns back to storage. Meanwhile, activities are controlled by software configurations. Similarly, for a biological system, we can see the physical body, consisting of cells and organs as the mechanisms that perform the expected, familiar activities. Input data consists of external stimuli from the system’s senses and memories retrieved from the brain. The output are the signals that influence the next activity or return to the brain as emotions or as new memories. Emotions, values and beliefs are the stored configurations that control the activity being performed. In a way, this system becomes what we would call the personality of the being, its essence, its character, its soul. A set of characteristic behavioural activities, driven by emotions, memories, values and beliefs, inputs from the external world and repercussions from previous actions.

It is interesting whether a model like this may be useful to try and capture the essence of psychiatric conditions like depression, anxiety, narcissism, schizophrenia, bipolar disorder?