A modern, secular argument for the immortality of the soul

I had meant to write this post a few weeks ago as an Easter/Passover/etc. present for my religious friends, but the first half of this quarter’s been pretty crazy. Anyway, here it is, better late than never!

We normally associate arguments for the immortality of the soul with the likes of Plato [1], Aquinas [2], and other ancient thinkers. Their proofs almost always implicitly or explicitly relied on certain religious assumptions, such as belief in a god, or at least of a kind of eternal,intangible, spiritual element to human existence. It seems impossible to argue for an immortal soul without relying on such assumptions, but that is exactly what I will attempt to do here. My argument should be just as believable for a religious person as it is for the most atheistic of atheists.

What is a soul?

That’s right Mauricio, what is all this talk of souls? Isn’t that already a religious notion? Well, it normally is. Here I will be using a somewhat different definition, with no religious or spiritual content.

The human soul

What is the essence of what we normally call a ‘soul’? It is a certain principle or thing which senses, acts, remembers, and thinks (many people, following Descartes [3], think of it as only a thinking thing). Many people think of it as being a kind of spirit, others think of it as a brain or mind. But what form it takes is not essential to what it is. If every human had a little blue baseball cap that was the source of all our thoughts and actions, we would probably call that our ‘soul’. So, since the actual form of the soul is merely accidental to it; what really defines the soul is its ability to sense, remember, cause our actions, and think.

All of these abilities and all our memories are encoded in our brains. If you really want to you can believe that there is some kind of spirit hovering around you or whatever, but the fact is that everything we do, think, say, or feel is causally reducible to some brain process. Even physical things, such as our body parts, are unnecessary parts of these abilities. One might think that you need eyes to see, but the eyes are not part of the soul, only the ability to receive impressions from the senses. Nor are our vocal chords part of the soul, but the ability to communicate. Similarly with every other part of our bodies, even the brain. Yes, the brain is where all these abilities are physically stored, and we have no way to ‘copy’ all our memories and thoughts out of our brains in practice (yet); but it should be clear to everyone that the brain is not the abilities, but it’s merely a receptacle for them.

The best analogy for this is a computer. Imagine I have Windows, or any other piece of software installed in my computer. It is clear that the computer is not the software, but it contains it. The physical hardware is what makes the software useful to me, in a sense, but the software exists independently of the hardware. Having a movie stored in a DVD may be useless without a kind of computer to read it and show me the movie through a screen, but the movie itself exists independently of the existence of any hardware capable of showing it.

Similarly, we can think of the brain as the hardware to the soul’s software. That is, the soul is a kind of algorithm. A series of stored memories, rules to receive impressions from the senses, rules to react to these senses. It may seem to us that human nature is not as deterministic as your usual computer algorithm, but it is still reducible to the same kinds of rules and principles. When my hand gets burned, I feel the pain, and I pull it away. This is a very simple example, but one can imagine how it can be extended to all kinds of human experiences. When I see a loved one catch a cab to the airport, all kinds of principles and memories cause me to feel sad, to cry, to wave goodbye; and then store the impressions of the event forever in my memory. This is a much more complicated process than anything a modern computed does, but it is still essentially reducible to a set of memories, rules, and principles for action. It is true that we do not always react in the same way to the same stimuli, our emotions and mental states have an effect, and there is perhaps some degree of randomness to some of our actions. But all of these mental states can be encoded in the algorithm of our minds, and an algorithm can even account for randomness where there is no predetermined rule for action.

Thus I take it for granted that the soul is an algorithm defined by the sum of our memories, thoughts, habits, and other principles for action.

The immortality of the soul

An algorithm can be written down as a finite list. So for any sense impression, I can write down a finite series of rules of how to react to them. For example:

  1. If you feel pain on your right hand, move your hand away from the source of the pain.
  2. Look towards the source.
  3. Remember not to put your hand on the source of pain in the future.

Obviously, these kinds of ‘sub-algorithms’ can get much longer and more complicated than that. Maybe a full characterization of a human’s algorithm would take much more storage space than the best supercomputers we have now (though I doubt this), but it should still be possible to break down the whole algorithm into a finite series of simple steps.

Now, in my example I wrote down the steps in the form of sentences, but this was not necessary. I could have written them as symbols, or anything really. Computers programs are usually written in binary due to certain physical constraints, namely that it’s very easy to encode a machine in binary, you can just put a bunch of lights, and if a light is on, it represents a 1, if it is off it is a 0. But one could represent an algorithm in any number system, and encode it in that number system in many different ways. For example, I could write a program that does the same thing in several different computer languages, and these would all be encoded differently on a computer, but the essence of the algorithm would be the same.

A piece of Napoleon's soul (probably).

Now let’s get back to souls. The essence of the soul is the algorithm itself, and this algorithm can be written in many different ways. But the algorithm exists independently of any representation of it. Think for example of the number ?. We normally represent it by the sequence of decimals 3.14159… But it can also be written in binary as 11.0010010000111111… Or in any number system really. I can also write it as a sentence, and say ? is the ratio between the circumference and diameter of a perfect circle. But nobody would deny that ? exists independently of these representations, not only as a constant of this universe, but even independently of the universe. Mathematical constants are like eternal features of the nature of reality, and they exist independently of any human who can count 1,2,3,…; independently of any computer that has them stored in its hardware; independent of everything.

The same is true of souls. Since they can be written down as a number (even if it is an unimaginably large number), then they must exist as that number, and moreover they must have existed since always, and they must always exist. The number that would become what I call my mind today must have existed since before I was born, and will continue to exist after today and until after I die. Of course, the algorithm that is now stored in my brain is constantly changing, but similarly when I install a new program on my computer it doesn’t stop being my computer. My soul is the algorithm which I am now, and that number has always existed and will always exist. Moreover, every algorithm which I’ve ever been and every algorithm I will be in the future has also always existed. So not only am I eternal as I am today, but every form which my soul has taken, every form it will take, and every form it could conceivably take, also exist and are eternal.

The Boltzmann brain

This is of course a different kind of existing from the usual sense. When I say I exist I usually mean my physical self, not this strange, abstract algorithm. And after I die, how useful is it to me that the algorithm which I was will continue to exist? Of course, it is completely useless. I cannot take solace in a kind of continued existence after death from this eternal algorithm. But I will offer one final thought, if only for entertainment.

Have you ever heard of a Boltzmann brain? A Boltzmann brain is a hypothetical concept which we owe to physicist Ludwig Boltzmann. The idea is that there are plenty of strange things that arise from the chaotic nature of the universe. Many of them even seem to have a certain kind of order, such as the Solar System. There is also a certain phenomenon called a quantum fluctuation, which is the creation of a particle and anti-particle out of a vacuum, i.e. matter out of nothing, but a Boltzmann brain need not arise through this process. Boltzmann’s idea is that due to the chaotic nature of the Universe, at any point in space-time, there is a non-zero chance that a whole bunch of matter will randomly coincide to create a self-subsistent, self-aware being.

And since your soul is eternal, this being could be you.

Author: Mauricio Maluff Masi

My name is Mauricio Maluff Masi. I come from Asunción, Paraguay. I’m a Philosophy PhD Candidate at Northwestern University. If you wish to contact me, e-mail me at mmaluff (at) gmail (dot) com. You can also find me on twitter at @mmaluff.

17 thoughts on “A modern, secular argument for the immortality of the soul”

  1. When you say the mind can be thought of as an algorithm, would it not be an algorithm that could change with external input? Indeed, you might well call it an evolutionary algorithm. So, if as you claim, you can write the algorithm down as a number, will this value not change?

    1. Yes, of course. I recognize that in the article towards the end. So in fact you could say there is a different (but related) algorithm for every ‘instant’ of your life, and each of these algorithms are also eternal. Moreover, there is also an algorithm for every possibility of who you could have been. For example, there may be an algorithm for a ‘me’ in which I never left home, or a ‘me’ that is still majoring in physics. So long as they’re internally self-consistent, there may be infinite versions of ‘me’ that exist in the sense an algorithm exists.

  2. Well, then it seems like the you’re holding a Platonist position on the philosophy of mathematics – you are claiming numbers are eternal. I don’t see how this has any significance for the brain.

    I have 7 book on my desk. Is this arrangement eternal because you claim ‘7’ is eternal? How does this differ from converting the arrangement of a brain into a number?

    1. I see what you’re saying, but I’m not at all a Platonist with regards to mathematics. I don’t give numbers any kind of ethereal existence outside of the world of experience. Numbers don’t ‘exist’ in a different plane or anything like that, they exist more as abstract organizing principles of reality. Sure, the arrangement of your books doesn’t exist outside your desk, but surely you agree that the number 7 does.

      Now consider the number which we may call the ‘organizing principle’ of your brain. The number clearly exists independently of the existence of your brain. Similarly, if I delete Windows out of my computer, it doesn’t cease to exist. But if I delete Windows out of every computer in the world, does it still exist? Well, perhaps not in the sense that we normally think of it. But if I make a random number generator spit out a really large sequence, and that sequence turns out to be Windows, I can install the sequence in my computer and it would work just as well. So it isn’t eliminated from existence in the same way a piece of paper is eliminated when I burn it, because Windows isn’t really a physical, tangible thing, but more of an abstract algorithm. My argument here uses a similar conception of the soul.

      Of course, I’m being at least a little facetious when making this argument, but I think what I’m saying is not inconceivable.

      1. Numbers and colors, among other things, are simple labels used to represent in short form the state of understanding in our brains for a given set of facts. Red for you might not be the same set of facts as red for me, but for both of us red seems to ‘exist’ – The way the mammalian brain works is amazing and understanding systems level programming is not an easy feat. When something like the number 7 or the color red are brought into the discussion we need to see these as labels, not concepts or objects or states. We could just as easily have called red things blippers… red just happens to be the label assigned to that particular set of facts as detected by our senses.

        1. That’s right. Philosophers normally call things like the color red and the number 7 qua experienced by us ‘qualia’. But I think you would agree with me that both the color red and the number 7 exist independently of our experience of them, even if they ‘exist’ in very different ways. Namely, red exists objectively as a bunch of wavelengths of light around 700nm, 7 exists objectively as a characteristic of a collection of things.

          Thanks to both of you for your comments by the way, this is a very fun discussion.

          1. I don’t particularly subscribe to the explanation that philosophers ascribe to such labels. Philosophers, to a man, don’t seem all to eager to admit that conscious intelligence is a by-product of multiple processes happening within our brains. While we may agree on the non-existence of red or 7, we do so for different reasons. All philosophy that I am aware of looks at life as though our brains function as a single entity and I’m not down with that. I am the representative of a hive mind. I am we, and we are I, there is no distinction between any of us working inside my skull to the outside world except where such test are able to detect the lag in communication from one part of us to the other. We, together, make me. You are as me, as inside you are many rather than a single entity. Decisions are made by command and control, not a singular control of all senses and muscles. Red is the label that ‘we’ give to that set of facts. It is clear that the set of facts exist outside of my senses… but the color red is experienced only by me in the way that I/we use that label. Your experience of those facts may indeed be different than ours, so we may speak between you and I of the color red and never mean the same things. It is not the color red that exists outside us, but the set of facts which we label as red which exist outside of and independent of us. In this way I disagree with philosophers as I think they see the problem in a bad way.

          2. You shouldn’t be so quick in putting all philosophers in a box like that. Here’s a clip of a philosopher (Searle) arguing exactly what you said, that intelligence is just a process happening in our brains: http://www.closertotruth.com/video-profile/Can-a-Person-be-a-Soul-John-Searle-/295

            I’m also a student of philosophy, and I would completely agree with you.

            “All philosophy that I am aware of looks at life as though our brains function as a single entity and I’m not down with that.”

            Before the 19th century perhaps, most philosophers nowadays would actually agree with you on this.

            “You are as me, as inside you are many rather than a single entity. […] Red is the label that ‘we’ give to that set of facts.”

            This is almost exactly what Heidegger argued in his opera prima, “Being and Time.” Some of the most influential philosophers of the past century, especially existentialist philosophers, would make the same argument as you.

            “In this way I disagree with philosophers as I think they see the problem in a bad way.”

            Yes, philosophers of old did see this in a bad way, following Aristotle. But more modern philosophers, starting with Kant in the 18th century would see the problem exactly as you do.

            I think it is a problem that most people see philosophers as unscientific, since many of the older ones seem unscientific to modern readers. This problem is exacerbated by introductory philosophy courses assigning mostly pre-18th century texts. But modern philosophers have a very scientific view of the world, and are very much in touch with scientific advances in all fields. I realize you’re not intentionally misinformed, but as a student of philosophy it hurts me to no end to see that kind of prejudice in people who are not very well acquainted with the field.

          3. I was careful to note that “All philosophy that I am aware of ” is how I viewed it. I am certain that I do not know all modern philosophy. That said I am still at odds with philosophy and neuroscience. At seemingly every venture from one into the other’s territory there is nothing but disagreement and the few bits they do agree on are simply wrong. Well, in my view they are wrong. It is possible that I do not fully understand either of them… just ask my wife, she’ll tell you. The trouble is that the hive mind that I spoke of is not accounted for in either philosophy or neuroscience, yet to me it makes far more sense. I think that perhaps there are others who think and feel as I do about this, but I have yet to meet them or read their works. To me, we are meat machines and operate as though we are not much different than a network of computing systems collaborating on things which affect all of the systems. My stomach sends signals which tells a part of my brain that I’m in need of sustenance, and other parts of my brain begin worrying about what might taste good while yet other parts are worrying about what places I might find viably good food stuff at this time of day. I’ll read a bit more and would be most glad to hear you have links to relevant information about philosophy that treats the mind as a hive experience.

          4. I realize you weren’t attempting to discredit all philosophy, sorry if I responded a bit harshly. Philosophy of mind is not at all my specialty, but I hope I can recommend some good reading on it!

            The one that I know most explicitly gives a similar picture of the ‘self’ (which he thinks is a silly concept in the first place) is Heidegger in “Being and Time”. Because he considers the concepts of soul and selves to have no real meaning, he uses the term ‘Da-sein’, which translates as ‘being-there’. Da-sein, he claims, is initially and for the most part defined by the ‘they’, which does not mean ‘the others’ in the sense we normally think of it, but more the people we would consider ourselves a part of. Thus even our language and almost all of our thoughts are merely things we inherit from other people. He does think, however, that we can have some authentic ‘thoughts’ (though he wouldn’t use that word), but only after we accept that most of what we say and do is defined by ‘they’. Unfortunately Heidegger doesn’t even bother to talk about bodies, since he was only able to write about a third of the book, and found himself incapable of finishing it. You could definitely think of his theory of Da-sein as a kind of ‘hivemind’ theory of the self. Unfortunately his writing is extremely technical, and I would not recommend reading it for pleasure unless you’re really into this stuff.

            A more modern philosopher with ideas similar to yours is Daniel Dennett. He also thought that most philosophy was very out of touch with the advances of neurology, so he tried to develop a philosophy of mind that made scientific sense. He rejects almost all philosophical jargon, and takes special offense with the word ‘qualia’. I haven’t read much of his work, but the most famous one is “Consciousness Explained”, and I suspect you’d agree with much of it. Like everything philosophical, however, do take it with a grain of salt and be critical of it, Dennett’s perspective is by no means universally accepted.

            As for your “body as meat machine” analogy, this is actually a fairly old view dating back to Descartes, and was considered the mainstream view for centuries (although Descartes thought of the ‘soul’ as being something separate from the body). Descartes’ “Meditations on First Philosophy” is a really easy, extremely beautiful read. I don’t really agree with most of the arguments he makes, but it is certainly much higher quality *writing* than most philosophers I’ve ever read. He talks a lot about god in the meditations, which was a bit shocking to me as an atheist the first time I read it, but if you can read it with an open mind and ignore the god parts it is a great read. I hated it the first time I read it, the second time it became my favorite essay ever.

            Anyway, I hope that was helpful, feel free to tell me what you think about these works, I would love to discuss them with you or recommend more reading. Philosophy may be my career of choice, but it is also my favorite hobby. And once again, thank you for commenting!

          5. Thanks for the reading suggestions.I’ll have to do some reading. I will admit that I’ve not found any videos etc. of Dennett to be compelling but I will look again with closer attention.

            My comment about being a meat machine was not meant in the manner that Descartes described it where the body is a machine controlled/occupied by the host spirit. If you can remember the character Data on Star Trek, a machine that struggled with understanding and trying to be human, this is exactly what each of us apes is doing. A process that would be made infinitely easier if there were in fact objective morality. I don’t remember Descartes pondering life as nothing more than a machine which is trying to understand life.I think that we are as Data is portrayed; machines trying to understand what it is to be human. A task, which on reflection, would seem impossible since even humans do not know what it means to be human, From there we can move on to what it means to be. Philosophy has left me wanting on both questions. There is no intrinsic or essential meaning to existence. Every attempt at explaining the meaning for existence fails when you ask if such is necessary for life. If the explanation does not hold and define that which is essential for life then it is not an explanation but merely an attempt to answer a question whose form is impossible to guess, let alone ask.

            Cogito ergo sum – now what? A question more devastating than the plague, yet one that cannot go un-asked. At the heart of the matter is the fact that there is no purpose or meaning to existence which existence cannot happen without. I mean that none of the explanations for existence are required for me to exist and so they are divorced from each other in profound ways. Perhaps this is the moment to que Dante. If this is a dream, wake me up. If this is a simulation, upgrade my software. I don’t want to contemplate existence, I want to know it. With that somewhat sad existential plea I am left with the thought that in fact maybe I do know it and this is it. The bald and ugly fact that this is what I seek. Perhaps it is fortunate that we live mere decades. Immortality would be unbearable.I can certainly see “why” people want to believe in an afterlife but I cannot believe any evidence for such.

            Philosophically, if this is it, if this is all there is to consciousness, how then should I spend my time? I’ll let you tell me what labels apply to me as I find none of them appealing for varying reasons. At times there is no joy in life and at other times it’s both fantastic and incomprehensible to watch a gnat dance around a spilled drop of fruit juice. To witness the choreography of the natural world is unending amazement. To find meaning in it is impossible. Meaning, as I see it, can only come from how I decide in this moment to interact with reality. The world, seen through such understanding as I have, does not fit Harris’ understanding of free will. We are, that is not our fault. That we continue to exist is.

          6. Sorry I’ve taken so long to respond, I’ve had a busy week. I think I understand your philosophy a bit more, sorry if I misinterpreted it earlier.

            Let me see if I can give you some quotes from philosophers that have said similar things:

            The first is from Heidegger, which I won’t directly quote because it doesn’t make any sense like that, but its in page 7 of “Being and Time”. He says that we as humans, which he calls Da-sein, have among our abilities the possibility of an inquiry about our being. We’re constantly trying to understand what it is to be human. Whether we can or not, was the question that guided the book, but unfortunately he was never able to finish it because he didn’t think he could write an answer. I think this is very similar to your position.

            Here’s one from Sartre, from “Being and Nothingness”: “Life has no meaning a priori … It is up to you to give it a meaning, and value is nothing but the meaning that you choose.” I think this is also close to what you’re saying. From the same book: “values derive their meaning from an original projection of myself which stands as my choice of myself in the world. […] I make my decision concerning them—without justification and without excuse” (72). That is, we decide what has meaning and what has not, what is valuable and what has not. There is no reasoning or excuse behind it, what we choose to make meaningful is what is meaningful.

            None of these people talk about bodies, but I think practically all modern philosophers agree with you on the ‘meat machine’ thing. Everything you do or feel or think or say is a consequence of some process in your brain.

          7. Thanks for the reply. In as much as they do not mention bodies, it can be said that their thought is agnostic of the platform on which is runs. I would think they would be as comfortable with a mind in a robot as they are with a mind in a meat robot. We have a tendency to feel or think that because society and collective thoughts are as they are for far longer than we have been individually that they have always been this way and were ordained for us rather than the simpler and more probable idea that this is what remains after we have tried all the really REALLY bad ideas. The kind that got us killed. Now we have collective thoughts and perceptions that represent the ideas that didn’t get us killed. There is no a priori meaning nor objective morality. There is but existence and non-existence. The body is not so much the thing, just as Hawkings. Sure, it’s nice and required for life, but a robot body would work too.

            I feel quite content in the thought that I agree with some philosophers now. Thanks for the reply.

          8. Not sure if you watch other blogs much, but Massimo Pigliucci called out Lawrence Krauss today for being one of many physicists that are critical of philosophy and philosophers.

            It is only in recent years that I have been interested in philosophy and that was an aside to trying to comprehend artificial intelligence. In fact the answer to the question “what is intelligence” has been my goal. I believe that I have a good answer but it is necessary that any such understanding should gel with previous philosophies and ideas or explain why it does not. Naturally neuroscience, compsci, physics, and many other disciplines are involved with such an effort. I’m not a professionally trained scientist, that should be clear.

            Many of the recent discoveries of neuroscience support my ideas, even if I say so myself. The discovery of a method for storing memories and a structure to the interconnections of neurons in the brain being two of these. It’s a surprisingly long road between what is the minimum definition of intelligence and how do we know what we think we know. On that road there is much of philosophy that seems anything but practical or useful so I have been searching for what is useful. I know that sounds suspiciously like picking facts to fit my hypothesis, but that is not what I’m doing. It’s more like asking the question “Why did Kant understand the transistor?” How could a Field-Programmable-Gate-Array have helped Nietzsche? Somewhere in the middle of such questions is, I hypothesize, the answer to how you stuff philosophy into a computer chip, or how do you get a computer program to be philosophical?

            That necessarily leads to personal evaluation of philosophy, ethics, what I do believe and why, what I can know and cannot, why there are inconsistencies in what I see as ethical and how the world works, why we think intelligent beings are capable and intelligent when they do what happened in Rwanda etc. My view of what intelligence is has changed a 1000 times in only a few years. There is cause to believe that intelligence in a vacuum is, at best, a waste. Without changing input or environment it cannot function. Before anyone panics, the human brain has enough noise in the sensory systems that even a brain in a jar should still dream etc. because that noise would function as changing data/input/environment.

            Anyway, that should explain a little bit of how I got to the meat robot point of view. It also explains, if you think about it, how I came to understand my brain as not a single entity but the convulsions of a hive mind where the constituent processes have a wont to cooperate. In fact, it is the cooperation of the several processes that lead me to understand consciousness as a necessary step to coordinate them, an emergent method to better feed all the cells of the body. We benefit from that because it is such a successful strategy. The trouble is that as the coordinators we are so far removed from the minutia of managing the processes of cells that we no longer can see the connections between a muscle cramp and being grumpy because we need more food.

            whoa… enough rambling

  3. That was very well explained. Given the quantum stuff you mentioned, which allows for a multiverse of possible infinite proportions, maybe your finite algorithm finds a place within one of the infinite other brains out there. In fact, it would kinda have to. The problem would be that, even though this other person would think just like you and may even have your exact memories, it wouldn’t be you. Your algorithm wouldn’t continue to evolve and change as you live your life, this person would live his life. (even though he is effectively a clone on you.)

    1. Thank you! I don’t necessarily agree with the Multiverse hypothesis, primarily because it’s unverifiable by experiment. But if it were true, yes, I believe your interpretation would be correct.

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