David's theory of evolution: Stephen Talbott's view; agency (Evolution)

by David Turell , Friday, November 13, 2020, 12:44 (1469 days ago) @ David Turell

Another author struggles with agency:

https://aeon.co/essays/the-biological-research-putting-purpose-back-into-life?utm_sourc...

Animal immune systems depend on white blood cells called macrophages that devour and engulf invaders. ... under a microscope you can watch a blob-like macrophage chase a bacterium across the slide, switching course this way and that as its prey tries to escape through an obstacle course of red blood cells, before it finally catches the rogue microbe and gobbles it up.

But hang on: isn’t this an absurdly anthropomorphic way of describing a biological process? Single cells don’t have minds of their own – so surely they don’t have goals, determination, gusto? When we attribute aims and purposes to these primitive organisms, aren’t we just succumbing to an illusion?

***

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.

Yet, on the contrary, we now have growing reasons to suspect that agency is a genuine natural phenomenon. Biology could stop being so coy about it if only we had a proper theory of how it arises. Unfortunately, no such thing currently exists, but there’s increasing optimism that a theory of agency can be found – and, moreover, that it’s not necessarily unique to living organisms. A grasp of just what it is that enables an entity to act as an autonomous agent, altering its behaviour and environment to achieve certain ends, should help reconcile biology to the troublesome notions of purpose and function.

***

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.
***

A popular narrative now casts all living entities as ‘machines’ built by genes, as Richard Dawkins called them. For Mayr, biology was unique among the sciences precisely because its objects of study possessed a program that encoded apparent purpose, design and agency into what they do. On this view, agency doesn’t actually manifest in the moment of action, but is a phantom evoked by our genetic and evolutionary history.

But this framing doesn’t explain agency; it simply tries to explain it away. Individual genes have no agency, so agency can’t arise in any obvious way from just gathering a sufficient number of them together. Pinning agency to the genome doesn’t tell us what agency is or what makes it manifest.

***

No one should suppose that macrophages are acting in the rich cognitive environment available to a wolf, but sometimes it’s hard to decide where the distinctions lie. Confusion can arise from the common assumption that complex agential behaviour requires a concomitantly complex mind.

***

To get to the nub of agency, we need to leave biology behind. Instead, we can look at agency through the prism of the physics of information, and reflect on the role that information processing plays in bringing about change.

***

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.

***

The crucial point of all this is that agency – like consciousness, and indeed life itself – isn’t just something you can perceive by squinting at the fine details. Nor is it some second-order effect, with particles behaving ‘as if’ they’re agents, perhaps even conscious agents, when enough of them get together. Agents are genuine causes in their own right, and don’t deserve to be relegated to scare quotes. Those who object can do so only because we’ve so far failed to find adequate theories to explain how agency comes about. But maybe that’s just because we’ve failed to seek them in the right places – until now.

Comment: Same old problem: top down or bottom up.