To be a good medical doctor, you have to treat the human body as if its parts have purpose and function. There’s really no way around it. That’s probably why medical doctors — the ones who aren’t skilled at compartmentalizing, anyway — often have difficulty looking at the world through a neo-Darwinian framework. Regardless of what they were taught in school, they know, from repeated daily experience, that function is foundational to life. 

I thought about this fact when I read the works of two medical doctors: oncologist Stephen J. Iacoboni (who has been doing a series of posts here on the science of purpose) and the maverick evolutionary theorist Stuart Kauffman. As physicians as well as thinkers about the problem of evolution, both men know that purpose is missing in the Darwinian framework. 

Indeed, there are quite a few striking similarities in their thought: 

• Both see purpose as a key aspect of life.
• Both have noticed that living organisms, and even large molecules, are not reducible to the laws of physics.
• Both argue that the idea of “purpose” or “function” only makes sense when combined with the idea of a “self.”
• Both talk of building a new paradigm for biology, where purpose takes center-stage. 
• Both believe that this paradigm shift would be revolutionary, comparable to the paradigm shifts of Galileo, Copernicus, Newton, and Einstein. 

There is, however, one big difference. Kauffman is a materialist, and Iacoboni is a theist. So Kauffman must explain life and even purpose in terms of matter and ultimately blind processes, while Iacoboni can invoke the supernatural. 

Since the theories of the two doctors have so much in common, it may be useful to compare them and ask: Who is able to give a deeper account of the telos, the purposefulness, of life? The theist doctor, or the materialist doctor? 

Iacoboni’s Theory of Purpose

Iacoboni begins his argument by noting that the most obvious thing about nature is its purposefulness. It’s not hard to see: DNA forms proteins that make eyes that enable bees to see and find pollen and make honey to survive and build hives… and on and on, without end. Though no one could deny this, Iacoboni suggests that the element of purpose in nature tends to be neglected by scientists as a consequence of neo-Darwinism, since the Darwinian framework has no place for such things as desires, plans, or intention. 

Yet, Iacoboni notes, the Darwinian story itself frames life as a cosmic struggle for survival, “nature red in tooth and claw,” where the most ambitious are preserved and the complacent are consigned to the garbage heap of history. So why struggle in the first place, Iacoboni asks?  

A Darwinist would no doubt reply: because creatures that struggle to survive are selected for. 

This is true. However, it doesn’t explain how the struggle started. That is, it explains why only the organisms that strive to live and reproduce still exist, but it doesn’t explain how or why the ancestor of all the organisms began striving. 

In other words, you have to posit struggle before you can get Darwinian evolution. And if you posit struggle, what you are really positing is desire, intention, will — purpose. 

Therefore, purpose comes before evolution. 

The Most Basic Characteristic of Life

Since the struggle to survive is the most basic characteristic of life, the question “Why struggle?” amounts to “Why life?” And Darwinism has no answer to this question. It’s not just that Darwinian evolution can’t explain that one little gooey common ancestor in the warm little pond back at the origin of life. In failing to explain that first organism, it fails to explain the characteristic of living organisms that most needs explaining: Why do living things, unlike all other conglomerations of matter, seem to act according to purpose or desire? 

Darwin’s worldview yields no answer that mystery, but to Iacoboni, it’s simple: purpose exists. The existence of purpose in life shows that purpose lies at the core of reality. 

Of course, “purpose” is not a law of physics. So Iacoboni says, get over the laws of physics. The fact that living organisms are intrinsically goal-oriented shows that they are not reducible to matter and the laws of physics. The problem with the current paradigm, he says, is that the physical structure of a thing is supposed to be its deepest nature, which leaves the thing’s function rather inexplicable. A better paradigm would start with function, and explain structure as the natural fulfillment of the function.

Of course, if you’re going to talk about the “function of a thing,” you need to define what “things” are, too. You can’t say what the function of an eye is without considering an eye, obviously. This seems like a potential difficulty, because in a reductionist framework where everything is just atoms and molecules, it’s not clear what delineates one “thing” from another. (Why do those specific atoms and molecules get to be grouped together and called a “thing,” and not those?)

The problem is solved if function comes before form. Iacoboni says we need to go back to the old view of Aristotle and Aquinas, who said that an entity is defined by what it can do. A thing has “properties” which grant it specific “powers.” Anything with the same properties and powers is the same “kind” of thing. So, for example, fire has properties that give it the power of producing heat and the power of producing light, and that’s what makes it fire. 

Objections from a Scientific Standpoint

Iacoboni realizes that someone might object to this from a scientific standpoint. It all seems very mystical, not to mention medieval. When has science ever discovered the “property of wetness” in water or the “power of sight” in eyes that Iacoboni’s beloved ancient and medieval scholars were so fond of invoking? 

Well, actually, Iacoboni contends, water does have the property of wetness and eyes do have the power of sight. It all makes sense if you stop trying to reduce everything to its parts. Just because a property emerges from a collection of parts doesn’t mean that property is not real. 

In fact, borrowing from Zen thought, Iacoboni goes so far as to say that the parts aren’t real. They do not really exist, except as an empty abstraction — in reality, only the whole exists.

To understand what he means, consider a tree. The bark does not exist except as a part of the tree — there is no reality where it actually exists in isolation from that context. The full picture is the reality. Any division in the whole is artificial, arbitrary. But you need to make divisions to define the parts. Therefore, according to this argument, the parts do not have true existence, except as (ultimately imaginary) delineations within the whole.

Iacoboni goes on to say that the laws of physics themselves are mere abstractions. They are descriptions of the regularities we have found in nature. They are not nature itself. A world where everything is reducible to these laws does not exist. So we have to look beyond them, to the emergent properties of the whole, and the powers those properties create. 

So what is the ultimate cause of these emergent powers and properties, if the laws of physics don’t explain them? 

Iacoboni’s answer is that purpose explains them. Of course, if purpose is the final cause of all the emergent properties in the material world, it cannot itself be one of those emergent properties. Instead, matter emerges from purpose. Iacoboni believes purpose is just as real as matter is — or even more real, because purpose causes the physical world, not the other way around.

Kauffman’s Theory of Purpose

So much for Dr. Iacoboni. What about Dr. Kauffman? 

Kauffman argues¹ that life is not reducible to the laws of physics, since you can’t explain life a priori from the basic rules of physics. In fact, Kauffman says that the universe is non-ergodic above about 500 daltons (which simply means that configurations of matter above a certain size are too improbable to be expected to happen by chance in the history of the universe). “The universe really will not make all possible complex molecules such as proteins 200 amino acids long in vastly longer than the lifetime of the universe,” Kauffman says. “…Because the universe is not ergodic on time scales very much longer than the lifetime of the universe, it is true that most complex things will never get to exist.” In other words, the laws of physics don’t explain anything other than simple molecules. Some other explanation is needed.

Like Iacoboni, Kauffman notes that there is an intrinsic element of purpose to all living things. Where does this purpose come from, then? Kauffman believes in the Darwinian explanation — natural selection, preserving traits that benefit the survival odds of the organism. But Kauffman pushes further, trying to deal with the same philosophical questions Iacoboni brought up: What is an organism, then? How can a collection of molecules be said to “survive” or “not survive,” when it will be a collection of molecules either way? And why does it struggle to survive? 

Kantian Wholes

Kauffman argues that living things cannot be reduced to their parts, because they are something he calls Kantian wholes: entities in which the parts exist for and by means of the whole. In other words, if you take out a part, the whole cannot exist, and if you remove the whole, the parts will not exist. 

For example: a chicken eye cannot exist without a chicken. It was made by the developing chicken, and if the chicken dies, the eye will disintegrate. Likewise, the lineage of chickens cannot survive for long without eyes. It’s the same for simpler systems, such as collectively autocatalytic molecular sets — without the whole cycle, the molecules that comprise the cycle wouldn’t exist, and vice versa.

This results in an objective and non-circular way of delineating group of molecules and calling it a discrete entity, an “organism,” without invoking anything spooky like a spirit or a soul (or a plan). This Kantian whole, in Kauffman’s view, is the “self” that is influenced by natural selection. In turn, this opens the door for a non-circular definition of function: “The function of a part is that subset of its causal properties that sustains the Kantian whole.” Because Kantian wholes are discrete selves, they can strive to preserve those selves: the Darwinian struggle for existence begins. 

Thus, “purpose” for Kauffman is an emergent property of causally closed loops that are self-creating (autopoietic). This, and not the laws of physics, is the true explanation for life. Because living things have purpose, they are able to create themselves. This means that they can achieve possibilities that wouldn’t have been probable and couldn’t have been predicted based on chance and the laws of physics alone.

In fact, Kauffman goes so far as to argue that these possibilities can’t be predicted at all. You can’t predict the evolving functions of living systems, because “function” is inherently unbounded and limitless. For example: who’s to say how many uses a person might find for a screwdriver? When you begin listing the possible uses, you realize there is no real limit: “The person could use it to unscrew screws…or to hunt fish…or hunt cicadas… or draw the Mona Lisa in the sand …or draw Mona Lisa riding a bicycle… or Mona Lisa dressed as Batman …” You can’t pre-state the set of possible uses the screwdriver might afford you, because it is intrinsically undefinable.

This, incidentally, means that you can never have true artificial intelligence from a computer algorithm, in Kauffman’s view. A computer algorithm must pre-state how the system will react to possible situations. That’s what an algorithm is: if this, then that. So if you can’t predefine the possible situations that might be encountered, an algorithm can’t deal with them. What you need is true creativity, which minds have, and computers cannot have. 

This is where Kauffman hits a wrinkle. If the mind isn’t like a computer program, what exactly is it? He says that life seems to make choices and create itself with intentionality and purpose. Where exactly does this “intent” come from, if there is no prewritten algorithm telling the organism how to respond to various situations? 

Probably it’s quantum physics, Kauffman decides. He writes: “This suggests that mind is quantum and perhaps that quantum actualization underlies the consciousness that allows us to see complex affordances.” Unfortunately, Kauffman is not a quantum physicist, and does not spell out the theory any further in his essay. 

The Choice

So there you have it. Which of these two explanations is the better?

Iacoboni’s explanation has the obvious disadvantage that he has to invoke the unexplainable. Science cannot directly observe “purpose”; it merely has to accept the evidence of things made by purpose. 

Kauffman, by contrast, is trying to explain everything in terms of the physical world, leaving nothing outside of the realm of science, nothing inexplicable. 

The disadvantage of his explanation is simply that he can’t do that. 

The trouble is, his explanation for life starts with self-creating systems, which is where a true explanation for life would end. For evolution to happen, Kauffman says you need a self-creating Kantian whole. Yet there is no reason why even the simplest possible self-creating system would just happen to be there, ready to go. The average molecular weight of a single DNA base pair is 660 daltons. But (according to Kauffman) any individual structure above around 500 daltons is unlikely in the history of the universe. So it’s not clear, in Kauffman’s system, why the first Kantian whole is anything other than a miracle. 

In other words, Kauffman’s account of life may be non-circular as a definition, but it is circular as an explanation. The concept of “Kantian wholes” merely explains how one could talk about “function” and “purpose” in a coherent way. It doesn’t explain how that function and purpose get there. It does not explain life, or the complexity of life.

The fact that Kauffman winds up vaguely suggesting that “mind is quantum” seems to show that he has nowhere else to go. You get the feeling that “quantum” here is equivalent to “magic” — the important difference being that materialists are not allowed to have “magic” things, but they are allowed to have “quantum” things. 

In the end, Kauffman’s explanation fails in the same place that Darwin’s explanation failed — in answering the question “Why life?” 

But of course, that’s the question. 

Iacoboni’s explanation, crucially, does not fail here: mind is the reason for life, and mind cannot be explained in material terms simply because it is immaterial. In fact, it precedes matter. 

This may in a sense be called unscientific, or not wholly scientific, because it admits of a realm beyond the reach of science. Be that as it may, it is the logical conclusion of what we have observed from science. As Iacoboni says: The laws of nature themselves, constant and fine-tuned as they are, point to something prior to the laws of nature. And of course, anything before the laws of nature lies outside the laws of nature, and anything outside the laws of nature is not natural. It is by definition supernatural. Therefore, as Iacoboni puts it, science “depends on what precedes science.” The natural world depends on what precedes the natural world.

How Could It Be Otherwise? 

If everything is caused by some cause other than itself, then the explicable must be caused by the inexplicable. Because there can’t be an infinite regression of explanations, everything must eventually lead back to something beyond human explanation. The observable universe is not a closed system, then. That’s too bad. But whoever promised us that it was? In the end, we have to believe in the world as it must be, not the world as we want it to be. 

Reasoning must be either linear or circular. If linear, it must lead somewhere other than itself — somewhere beyond reason, that is. A circle goes on forever, because it goes nowhere. But a chain of reason cannot go on forever. The succession of “whys” must eventually reach a destination. So if you follow reason to its logical end, you always find yourself with something inexplicable, a causeless cause, a foundation of reality with no reason beyond itself. 

It’s like a path leading to the ocean. You can linger on the path, and try to believe that the path is the whole world. But if you follow it all the way, you will have to step off. 

Of course, not everyone wants to step off. Not everyone wants to consider (much less encounter) the supernatural. If you can’t handle it, you will try to close the loop, and settle for the “cramped eternity” (as G. K. Chesterton put it) of circular reasoning instead of the terrifying possibility of the true infinite. 

You might end up talking about how life creates itself, and how it is able to create itself because it is self-creating. 

Or something like that.

Reason, if you follow it all the way, leaves you with only two options: face God, or be stuck in a futile loop forever. Stephen Iacoboni demonstrates one choice, and Stuart Kauffman, the other. 

Notes

1. Stuart Kauffman and Andrea Roli, “Beyond the Newtonian Paradigm: A Statistical Mechanics of Emergence.” in Evolution “On Purpose”: Teleonomy in Living Systems (MIT Press, 2023).