British science writer Philip Ball offers us a guide to a very interesting project: an attempt to “naturalize” the idea of agency, that is, make the desire to do things—the mouse’s desire to escape the cat— explainable from a fully materialist perspective.

That’s much harder than it seems. Rocks don’t desire anything. So we can’t just start from the bottom. It’s also not enough to say that the mouse wants to avoid getting killed. That’s true but it doesn’t really explain anything.

For example, a person looks both ways before crossing the street to avoid getting run over. But, by itself, that doesn’t explain why she tries to avoid getting run over. One must factor in her memory, background knowledge, will to live, and such, to explain her behavior. A tire rolling downhill would not alter its course even though it might get run over because it does not have any mental attributes.

There is no science explanation, at present, for why life forms, human, animal, plant, or bacterium, strive to go on living but rocks do nothing to avoid becoming sand.

Philip Ball, author of How To Grow A Human, offers some thoughts on the problem:

One of biology’s most enduring dilemmas is how it dances around the issue at the core of such a description: agency, the ability of living entities to alter their environment (and themselves) with purpose to suit an agenda. Typically, discussions of goals and purposes in biology get respectably neutered with scare quotes: cells and bacteria aren’t really ‘trying’ to do anything, just as organisms don’t evolve ‘in order to’ achieve anything (such as running faster to improve their chances of survival). In the end, it’s all meant to boil down to genes and molecules, chemistry and physics – events unfolding with no aim or design, but that trick our narrative-obsessed minds into perceiving these things.

Philip Ball, “Life with purpose” at Aeon (November 13, 2020)

Ball is not satisfied with that but he wants a theory of agency that arises “bottom up,” presumably from electrons and quarks. Still, he does not wish to adopt the panpsychist approach and say that consciousness is an underlying feature of the universe. He wants mind from mud, thoughts from watts.

How is that going?

A bottom-up theory of agency could help us interpret what we see in life, from cells to societies – as well as in some of our ‘smart’ machines and technologies. We’re starting to wonder whether artificial intelligence systems might themselves develop agency. But how would we know, if we can’t say what agency entails? Only if we can ‘derive complex behaviours from simple first principles’, says the physicist Susanne Still of the University of Hawai‘i at Mānoa, can we claim to understand what it takes to be an agent. So far, she admits that the problem remains unsolved.

Philip Ball, “Life with purpose” at Aeon (November 13, 2020)

We are offered a sketch of what a solution might look like.

Confusion can arise from the common assumption that complex agential behaviour requires a concomitantly complex mind. In the ordinarily sedate waters of plant biology, for example, a storm is currently raging over whether or not plants have sentience and consciousness. Some things that plants do – such as apparently selecting a direction of growth based on past experience – can look like purposeful and even ‘mindful’ action, especially as they can involve electrical signals reminiscent of those produced by neurons.

Philip Ball, “Life with purpose” at Aeon (November 13, 2020)

Very well but if plants behave like animals, we have hardly established the idea that intelligence is bottom up and that there is thus no intelligence behind the universe. The question, in the case of plants, is how they engage in what seem like cognitive functions without any of the machinery animals use.

Ball prefers to leave biology for a moment and look at physics, specifically the physics of Erwin Schrödinger (1887–1961):

Schrödinger believed that the apparent agency of life was sustained entirely by encoded instructions that specify its responses to the environment. And it’s certainly true that the mechanical readout of instructions shaped by evolution and stored in some molecular form – which Schrödinger called an ‘aperiodic crystal’, and which Crick and Watson identified as DNA – explains a great deal about how living things work. But that view leaves no room for the contingent, contextual and versatile operation of real agency, whereby the agent has a goal but no prescribed route to attaining it.

Philip Ball, “Life with purpose” at Aeon (November 13, 2020)

Even so, he is optimistic about current research:

This link between organisation, information and agency is finally starting to appear, as scientists now explore the fertile intersection of information theory, thermodynamics and life. In 2012, Susanne Still, working with Gavin Crooks of the Lawrence Berkeley National Laboratory in California and others, showed why it’s vital for a goal-directed entity such as a cell, an animal or even a tiny demon to have a memory. With a memory, any agent can store a representation of the environment that it can then draw upon to make predictions about the future, enabling it to anticipate, prepare and make the best possible use of its energy – that is, to operate efficiently.

Philip Ball, “Life with purpose” at Aeon

Well yes, but where does the memory come from? Why does it arise in life forms but not in rocks?

‘Most real systems, especially biological ones, have “perception filters”,’ says Still, ‘which means they can’t access the underlying true state of reality, but only can measure some aspects thereof. They are forced to operate on partial knowledge and need to make inferences.’

Philip Ball, “Life with purpose” at Aeon (November 13, 2020)

Indeed. But the question we are trying to answer is not why life forms rely on partial knowledge but rather why they have any knowledge at all. Rocks don’t do anything like that.

There are still wrinkles in this picture. In general, the environment isn’t a static thing, but something that the agent itself affects. So it’s not enough to simply learn about the environment as it is, because, says Still, ‘the agent changes the process to be learned about’. That creates a much trickier scenario. The agent might then be faced with the choice of adapting to circumstances or acting to alter those circumstances: sometimes it might be better to go around an obstacle, and sometimes to try to tunnel through it.

Philip Ball, “Life with purpose” at Aeon

Sure. But what’s the what that enables a life form to frame that choice when thousands of boulders just sit there utterly devoid of such a mind in the background?

And finally,

Here, then, is a possible story we can tell about how genuine biological agency arises, without recourse to mysticism. Evolution creates and reinforces goals – energy-efficiency, say – but doesn’t specify the way to attain them. Rather, an organism selected for efficiency will evolve a memory to store and represent aspects of its environment that are salient to that end. That’s what creates the raw material for agency.

Meanwhile, an organism selected to avoid predation or to forage efficiently will evolve an ability to generate alternative courses of action in response to essentially identical stimuli: to create options and flexibility. At first, the choice among them might be random. But organisms with memories that permit ‘contemplation’ of alternative actions, based on their internal representations of the environment, could make more effective choices. Brains aren’t essential for that (though they can help). There, in a nutshell, is agency.

Philip Ball, “Life with purpose” at Aeon (November 13, 2020)

No. There, in a nutshell, isn’t agency. That is, it doesn’t make sense to say that an organism is “selected for” agency or efficiency, with no agent selecting it. If the life form’s choices don’t remain random but suddenly become the object of the life form’s “contemplation,” how do we account for that fact? What exactly happened to make the life form able to contemplate?

It turns out that the “bottom up” thinkers are still working on that problem. No surprise. There are two big obstacles here. First, information is very difficult to co-ordinate with matter and energy. Information is measured in bits and bytes, not in kilograms and joules. There has never been any compatibility between the two systems.

Second, when it comes to life forms like humans, the issue of purpose or goal-directedness is almost certainly part of the Hard Problem of consciousness. Which means that the bottom up theorists will likely be working on their theory for a long time, something like forever.

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