Models vs Theories

I’m loosely borrowing the language of models and theories from the scientific world. If you present a theory, you will often be expected to give a somewhat comprehensive explanation and description of how something really is. If, on the other hand, you present a model, you will be expected to give a useful way of thinking about something or making calculations about it.

For example, if you’re teaching the gas laws, you might model molecules as solid bouncy spheres. Of course, you would not be claiming that molecules really are solid bouncy spheres, and in fact we know that they are very different from that. A more accurate description, however, which might involve atoms and sub-atomic particles etc., will not help you in this context. If you go further and describe particles as blobs of quantum goo, you’ll be even further from communicating an intuitive understanding of bulk gas properties.

Multiple models are often necessary in a single area. The most obvious example of this is wave-particle duality in quantum physics. In some circumstances, you need to be able to think of light – and the rest of matter – as being composed of particles, other times as waves. In would be nice if our brains had a single intuitive model that incorporated both of those naturally, but it seems we don’t.

A model is more humble than a theory. When you use a model, you are conscious of the fact that there will always be a gap between your understanding of reality and reality itself.

If these things are true for understanding those parts of reality that can be more readily measured and tested scientifically, it shouldn’t surprise us if we need to think about revealed, spiritual reality in a similar way. It turns out I’m not the first to apply this way of thinking to theology: for a fuller discussion, see the “Mystery and Models” section of J.I. Packer’s lecture on The logic of penal substitution.

The component theory

The model I’m about to describe stands in contrast to what we could call a “component” theory of human nature. That theory takes some of the language found in parts of the Bible where a person might be described as being made up of “body” and “soul” (e.g. Ecclesiastes 12:7), and considers this language of us having different “parts” as being more than a model, but a complete description of reality – soul and the body are the two constituents from which a whole person is constructed. Put the two together and you’ve got a real person. While one is subtracted (death), you no longer have a person.

This division in itself has not been controversial, with many noting that as well as “soul” and “body”, in the Bible there is also mention of “spirit”, leading to debates between the bipartite and tripartite camps.

Both camps get into trouble with the biblical data, because the Bible simply doesn’t use its own terminology consistently. Sometimes it even refers to the whole person as a “soul” – for example, Genesis 2:7 says that the man God created became a living “soul” (Hebrew “nephesh”), seemingly referring to the whole person, and 1 Peter 3:20 refers to the people on the ark as “souls” (Greek ψυχή which can be translated soul or life). As another example, when the Bible commands us to love God with all our heart, soul, mind and strength, we wouldn’t conclude there are actually 4 components that make up the person.

A component theory of body and soul quickly gets you into difficult theological and philosophical issues, especially regarding how the two interact. I think increasingly many Christians have seen how the bipartite (or tripartite) positions are problematic from a biblical perspective and have seen the need to emphasise the fundamental one-ness of human nature.

A dualistic, component theory also becomes pretty problematic in the light of many advances in science, especially neuroscience. As we understand more and more about what different parts of the brain do, we are going to increasingly discover the role of the brain in moral and ethical judgements, and in spiritual experiences. Those who lean on a component theory of body and soul are going to find the soul continually shrinking and becoming a victim of a “soul of the gaps” ideology, just as a God of the gaps approach to the physical sciences results in God disappearing.

How I think about the soul

If I remember correctly, the seed thought in the analogy that follows is from a book called “The Pig That Wants To Be Eaten”, by Julian Baggini. I no longer have my copy of the book, so I’m not sure whether I have developed, misrepresented or just wholesale plagiarised the ideas found there – but I certainly don’t claim originality. The thought here could also probably be expressed in terms of other ideas from philosophers, but I like this better.

The analogy: what is “a piece of music”?

That seems like a pretty hard question in itself. To make it more concrete, let’s pick a famous piece. I was going to choose Rachmaninov’s Fourth Piano Concerto, because the tune often goes round my head, but Bohemian Rhapsody is a bit shorter to type – feel free to substitute with anything of your own choosing, preferably something with a tune you can call to mind easily.

A specific piece of music like Bohemian Rhapsody could be defined as a certain sequence of sound waves – a far from perfect definition, but we have to start somewhere. But now we could ask: once the sound waves have died down, does that piece of music still exist?

I think most people would agree that even if no-one were playing Bohemian Rhapsody right now, it would still exist in our world – firstly because we have lots of recordings of it, on various physical media and sheet music. If someone somehow succeeded in destroying all of those, we could still say that it exists in many people’s memories. Between us we would probably do a pretty good job of reproducing it.

However, once the last recording is gone, and the last person who remembers it has died, I think it would be fair to say that it has finally been lost or destroyed.

So, in order to exist, a piece of music needs to have a physical form. But that physical form is not limited to just one medium. We can also note that there might be many different recitals or recordings of the same song which cannot be identical, and yet are all somehow, in some sense the “same” song.

So much for the analogy. The question we are really thinking about is this: what is a human being?

As humans we are fundamentally physically. My body is me, and I am my body. And the future hope of Christians involves physical bodies in a physical world – that is the resurrection we are promised and are waiting for.

Yet, we are aware that we are more than our bodies, and Biblical language reflects that.

And what about after death? The idea of a disembodied soul or a disembodied existence is a very strange one and very difficult to square with our fundamentally physical nature. Yet the Bible does talk of being “with God” immediately after death, long before the promised resurrection.

So is it possible for a human being, like a piece of music, to be “recorded” and “played back” somehow?

What if there was a perfect, infinite mind that was able to know every part of who am I, body, mind and spirit? If God, at the point I die, captures in his mind every detail about me, and not just the physical aspects of my final state, but the fully 4-dimensional reality of everything I ever did or thought, everything about who I really was, could you say that I still existed? What if God was able, with his infinitely powerful and precise imagination, to think about me, to lovingly recall me to his mind so perfectly and vividly that it became a genuine existence for me?

What if that’s what I mean when I say “my soul is going to be with God”?

There are a number of things I like about this model:

• It emphasises the goodness and importance of our physical nature.

• It fully escapes the “soul of the gaps” trap, and frees us from looking for ways that body and soul “interact”.

• It frees us from having to answer questions like “when does the soul enter the body of the unborn child?” The answer to that question that would have big ethical consequences, but it’s question which the Bible doesn’t actually address, let alone answer. I think it’s the wrong question, based on a wrong theory.

• It rightly makes the “intermediate state” a definitely inferior and strange form of existence, compared with the resurrection we are looking forward to.

• While emphasising the fundamental physicality of the body, it still makes a distinction between “who I really am” and “my body right now”. It allows for the idea that the body can somehow be a less than perfect representation of the real person – just as you could have an imperfect performance of Bohemian Rhapsody that somehow still “is” Bohemian Rhapsody. This is helpful for other things in life – for example, in thinking about illnesses or disabilities, including mental illnesses and the deterioration of the body in old age.

There are certainly weaknesses in this model, but I think that’s fine – it’s not supposed to be the only model. I don’t think it can claim to be “Biblical” – it’s what Packer would call a “secondary” model, rather than a primary one. I don’t even think it is “correct”, in the same way that “molecules are solid bouncy balls” is not “correct”.

It’s just one way of thinking about the subject that I don’t think contradicts what the Bible teaches, and can be helpful to us in some contexts – especially, in showing that there are other ways of thinking about what the soul is in the context of a growing understanding of the brain that makes substance dualism increasingly untenable. I found it helpful for thinking about a subject that is full of deep mysteries, my wife didn’t think it was completely heretical, so I thought it was worth sharing.