Michael Levin and Daniel Dennett have an interesting article up at Aeon, on the right way to talk about purpose and cognition in biology, particularly in simple organisms and lower level mechanisms. The core thesis is that an organism, at any level, all the way down to a single cell, is an agent, with its own agenda and goals.
They are careful to stipulate that they’re not saying these simple systems are conscious. Biologists often talk about these organisms and mechanisms as though they have purposes and agendas. For example, a biologist might say that a plant “wants” its seeds to be consumed by animals so they’ll eventually be passed in locations far and wide.
But most biologists, if pressed, will say that they’re only talking metaphorically. In a way, this is similar to the usage physicists and chemists use when they talk about what an electron “wants” to do, or which atoms want to bind with each and which have an aversion to each other.
Levin and Dennett argue that biologists should stop worrying about the metaphor caveat. That it’s actually holding back higher level theories about these systems. Systems can have goals and purposes without understanding. In a phrase Dennett has been using for the last few years, they can have competence without comprehension. There may be something to this stance.
Biologists, at least the ones in the US, have been leery of this approach, partly I think to avoid confusion between the scientific view of evolution, which is unguided, and the version often imagined by the public, that it’s guided, at least in part, by a deity. All the battles with creationists and intelligent design advocates over the decades haven’t helped. But those battles seem to have dwindled in recent years. Maybe we’re at a point where evolved purposes can be discussed without theological confusion.
Of course, I can see a lot of biopsychists, those who see all life as being conscious, objecting to Levin and Dennett’s caveat that these goal seeking systems aren’t conscious. For that matter, I can see panpsychists objecting that it’s wrong to draw a boundary at biology, since physicists and chemists do often use the purpose language for what they study.
But as the article mentions, the laws of physics give us a good idea of what an electron will do in any particular situation. They aren’t nearly as useful when considering what a mouse will do. Yes, it’s all physics and computation, but the functionality of a living system adds far more complexity, and arguably requires modeling at higher levels of organization.
Levin and Dennett discuss an important measure of the intelligence of a system, how broad its scope of concern is. A simple system, such as a worm, often just responds to immediate stimuli it receives from the environment. A more sophisticated system takes in information and responds to a wider spatial area. An even more sophisticated system considers information over increasingly larger time scales. Humans, of course, have a very wide scope on this scale, spatiotemporally wider than anything else we currently know of. (This resonates with the hierarchy I sometimes discuss.)
One area the article doesn’t touch on is artificial intelligence systems. In some ways, they’re going to mess up the spatiotemporal scale, because it’s generally easier for technological systems to take in information from a wide variety of sources than it is to make use of information in the immediate environment. It’s the old conundrum that what’s easy for humans (or other animals) is often hard for machines, and vice versa. Of course, with these types of system, no one is shy about discussing their purposes, since the engineers are typically there to tell us about those purposes.
What do you think? Should we just get over the aversion to discussing purpose in cells and other lower level biological mechanisms? What about in proteins? Or even non-living systems? Or are we just reifying metaphors and confusing ourselves? Should we maintain a distinction between teleology, the existence of purposes and goals, and teleonomy, the appearance of such goals?