How do we define life? If you asked this question to a biologist, he or she would point you towards the seven commandments of life science (‘thou shalt metabolise’; ‘thou shalt adapt’; ‘thou shalt reproduce’ etc.) Life, they would say, is a label we give to anything displaying these seven features. This stone tablet has been able to bestow the status of ‘living’ unto all the fish and trees and mushrooms and amoebae that biologists have so far wanted to study. However is this statutory definition enough?
I don’t think it is. It seeks to sort any given collection of molecules into one of two camps: ‘living’ or ‘not living’. It’s a tautological distinction that takes no prisoners. Importantly, rather than attempting to form a truly encompassing definition, all it does is list seven characteristics that are common to everything that had already been colloquially defined as life! It is no more of a definition than an affirmation. It in no way reflects the complex nature of, well... Nature.
An individual mammal and the cells inside it are both considered to be living in their own right. Contrast this with a swarm of bees which isn’t generally thought of as an organism in of itself, but rather a collection of organisms. Our intuition seems to only accept something as living if it’s encapsulated in its entirety by skin, scales or a membrane. Yet in many ways a swarm or hive will act as a single coherent organism when reacting to a stimulus. A hive is even organised into subsystems (workers, soldiers, a queen etc.) which all interact with each other in a way that’s fundamentally similar to the way cells interact in a mammal.
We live in hives too, but we call them cities.
Cities are often described through metaphors such as ‘thriving’ or ‘alive’, but are these more than metaphors? A city metabolises coal to power and heat itself, it has a body clock and transport network, it’s organised into cells (us) which function to keep it homeostatic, it can grow and die, it adapts to environmental changes over time...
Despite all this it we as humans remain very objectionable to the idea that a city might be an actual living organism. But then again, if a red blood cell could philosophise would it too reject the notion that its host was in some sense just as much an individual as it was? Would it not ascribe the seemingly intelligent behaviour of the human it lives in to the computational work performed by individual neurons that it supplies oxygen to rather than the human itself? The human would certainly ascribe intelligence to itself! Or its brain, where it considers the ‘seat of its consciousness’ to be.
In what ways, then, is a computer different to a brain? While I’m not going to get into a discussion of consciousness, I will raise the question: do computers think? Well, they don’t think like a human, but that’s not to say they don’t in some sense think. In any case, the answer certainly isn’t either a yes or a no, but complex and multi-faceted one.
And I think this is true not just of thought but of life itself. The questions raised here are ones that cannot be addressed (or even asked!) by the limiting definiton that biology has given us. In this sense it is blind to many possibilities of life that we could learn from. Life cannot be defined in such a way that makes it a binary digit (either living or not living). Nor should it be a scale of 1-10. If anything, it’s a many-dimensional vector. The seven pillars should not serve as committee in charge of (lifelong?) membership to the Living Club. Rather, they should be thought of as a set of features that emerge out of the complex behaviours characteristic to life and governed by evolution. Life, if anything is a single individual composed of sub-individuals, sub-systems, subsub-individuals, self-similar on many scales, all interacting, all ecompassing. It is a networked fractal array of cogs and axels but most of all: hugely, vastly, complex.
