I love chapter 4 of Michael Leyton’s Symmetry Causality Mind, titled Representation is Explanation.
The premise of this entire book is that we only have access to the present. Our experience of the past is constructed by our minds based on shapes in the present which we can use to causally infer the past. These shapes range from graffiti on the wall which we infer was the trace of the artist’s hand movement to arrangements of neuronal matter (memories) which we infer were caused by an episode in the past.
Note the distinction: we do not have access to the past, we only have access to a shape in the present (a memory) which we use to infer the past.
Our behavior co-opts this property of the universe. It’s useful for me to have a model of the past, so I habitually create shapes to represent my experience, recording memories in my mind, in writing, etc. so that in the future I can look at these shapes to infer the past. In Leyton’s words, “the writing of memory alters an object in order to determine the past that will be inferred from it.”
This process is beautifully illustrated in the movie Memento. The main character, due to a mental condition, can’t create long-term internal memories so he needs to create all of his memories externally by taking polaroids, writing constantly, and storing memories in other people, for example the clerk at his motel who tells him his room number (and has rented him several rooms).
Our model of our self is often as a contained entity which has persisted through time, apart from the world. But taking Leyton’s perspective, I see myself as a “pattern integrity”, newly existing at every instant of the present, which reads from memory within my body but also smeared across external space, to determine its co-evolution with the world.
This morning I was reading The Quantum Biologist’s post on peacocks and peacock spiders. I was struck by the existence of higher-level pattern integrities which use memory in the same way. As argued above, a human only has access to the present, so we set up systems (e.g. memory recording) by which a model of the past can be inferred, so that we are more adept at steering our path in the world. Likewise, the evolution of a species only has access to present. It has no direct access to what has worked or not worked in the world. So when it makes decisions, i.e. when mates are chosen, it uses features of the present to infer the past.
Evolutionary biologists argue that a peacock has huge feathers for the sake of having huge feathers. That is, the peacock’s huge feathers impress peahens because they show that they are successful enough to grow and carry around huge feathers, an otherwise useless feature.
In this way, the peacock’s feathers are a memory by which the peahen can infer the peacock’s past. This behavior is self-reinforcing. By mating with a peacock with impressive feathers, it is likely that the peahen’s chicks will also develop impressive feathers and have a better chance of finding a mate. The feathers serve as a memory for the entire lineage of peacocks.
This memory system is not just a crude “I made it” signal, but has evolved into its own elaborate language.
A footprint in the sand and a word written in the sand are both memories that allow us to infer the past. The difference is that the causal processes leading to the footprint are much more intrinsic to the world, depending on things like feet and gravity. The word, on the other hand, draws on a specific causal history that has been propagated and elaborated by a rich history of causal feedback loops, the evolution of the language.
The peahen’s aesthetic value system, which involves the patterns of “eyes” on the feathers and the way the feathers move, is likewise not intrinsic to the world. It is a specific language that the evolution of the species, when seen as a pattern integrity, has developed to store memory.