After my speculations, aided by various authors, about whether trees are intelligent, or even fungi, Peter Godfrey-Smith has settled me down a little. While I was returning Merlin Sheldrake's Entangled Life to the library I saw his book Metazoa: Animal Minds and the Birth of Consciousness sitting awaiting re-shelving, begging me to borrow it.
Historically, theories of mind have varied widely. One view is that the mind (perhaps equivalent to or similar to the soul) is an add-on which co-habits the body but is separate from it, so when you die your mind/soul may continue on and perhaps enter another body, or travel up to God. Another theory is that the mind emerges from the brain and is produced by it, but is not the brain itself.
Godfrey-Smith rejects both of these - he is a monist and a materialist, and in his view the mind does not emerge from brain activity or get added to it, it is that activity. This is easy to say, but it raises a whole lot of questions which Godfrey-Smith works his way through methodically with a mixture of science and philosophy, but mostly science.
In his view, two things are central to the existence of a 'mind' - identity and agency. Identity means that the creature has a sense of itself as a particular being in contrast to other creatures and objects. Agency is related to coordinated action and intention - the creature must decide to act and be able to carry out this intention.
The difficulty is in knowing which creatures share these characteristics and which don't. He suggests, for instance, that sponges probably don't - it is not always clear where one sponge begins and another ends, and sponges can be divided and remain viable. Lobsters, on the other hand, seem to have both. He describes his observation of a rock lobster, a mass of legs and feelers, feeling around itself constantly, at one point grabbing its own leg in its pincer and then immediately releasing it. He also describes lobsters observing other creatures and interacting with them.
Then there is the example of octopuses. Octopuses have what could be thought of as nine brains - a large one in its head, and smaller ones in each arm, connected to one another by tangles of neurons. At times the arms appear to act independently of the body, at others the whole octopus pulls itself together as it were and acts as a unity. So is the octopus one creature, or is it nine? Does it have one mind, or nine minds?
To illuminate this question Godfrey-Smith spends a good deal of time in a digression on humans with split-brain conditions. The upper part of the human brain, the cerebral cortex which is believed to be the main site of cognition, is split into two halves or hemispheres. Each hemisphere controls one half of the body - the left hemisphere receives signals from the right eye and controls the right side of the body and vice versa. Different hemispheres also have different functions - the left controls speech, for instance, while the right controls spatial awareness. They are connected by a kind of heavy-gauge cable of neurons called the corpus callosum. This connection is sometimes deliberately severed as a treatment for severe epilepsy, preventing seizures from travelling from one hemisphere to the other.
People who have had this procedure have been the subjects of extensive research over the years to determine the precise nature of the two hemispheres. This research demonstrates that the hemispheres often think and act independently of one another. If you cover a person's right eye and show them something via the left (sending a signal to the right hemisphere) the person will be unable to say what the object is, because the left hemisphere, which controls language, is unable to see it, even though the right hand will be able to pick it up and use it appropriately. If the person is struggling to say the name, in some cases the right side of the brain will attempt to communicate the information to the left - for instance, but having the left hand trace written words on the right hand.
Obviously, most of us never experience this as our two hemispheres are able to communicate freely. But are we, in fact, two people - two minds - in one? And to go to the more elaborate case, are there in fact nine minds in an octopus? He doesn't attempt to answer this definitively but seems to suggest that it may be both. Depending on the situation the parts of the brain may operate independently of one another, but can switch instantaneously into functioning as a unity when required - for instance, to attack prey, flee a predator or get up to answer the phone. The switching happens without our conscious awareness.
The other factor involved in mind is the capacity for learning. Humans, of course, are great learners and we know that other mammals can learn too, but what of other creatures? He points to surprising findings from observation and experiments. Take for example the archer fish, a little freshwater fish that hunts by squirting water at insects to knock them into the water and then capturing them and eating them. Most archer fish shoot at insects that are sitting on leaves or branches or on the bank, but some learn to also shoot them out of the air. In a community of archer fish, if one discovers this trick others seem able to learn it just by watching - the first will experiment for a while until it hits reliably, then the others will do the trick right the first time without needing to practice.
Other creatures also display the ability to learn. For instance, bees can be trained to recognise the number of blotches on a piece of paper hung at the entrance of the hive and turn left or right depending on the number displayed. Yes, that's right, bees can count, at least up to three! Insects are also shown to exhibit behaviours and reactions which seem to be the same as those which in humans are associated with mood or emotion - it is quite possible that insects can be happy or sad, excited or fearful, and so on.
This is a book about animals, but he does deal briefly with the question of plants. In contrast to Peter Wohlleben (or indeed, Merlin Sheldrake on fungi) he thinks they probably don't have minds or 'think' in the way animals do. They lack two things that he sees as key to the existence of mind - nervous systems, and centralised processing. Although they do pass electrical and chemical signals around their bodies, and even exchange signals with others, they don't seem to have a clear sense of identity - where they start and other creatures end - or of agency. Disappointing perhaps, but hardly the last word on the subject given the brevity of his consideration.
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What I find interesting about this is that even in a work as scientifically based and rich in evidence as this one, there is a barrier we can't cross. We know what is going on in ourselves, at least to some extent (bearing in mind the massive scope of our unconscious minds) and the gift of language means we can know that other humans experience something very similar. Our knowledge is far from complete - we don't all share the same language, nor the same culture, and translations are imperfect. Someone once said that we all smile in the same language but actually we don't - even a smile can mean something different depending on your culture. But at least we can reach some sort of approximation of what others are thinking and feeling.
As soon as we cross species, we are in the dark. Our lack of a shared language means that we must inevitably speculate. In doing this, it is almost impossible to avoid anthropomorphism - treating other creatures as if they are like us. When we look for consciousness, for a mind, what we are doing by default is trying to see how much other creatures are like us.
Of course it's quite possible that when a dolphin, a bird or even an octopus or a bee appears to be thinking, it is doing something similar to what we would do. After all, we are ultimately all branches of the same evolutionary tree, with common genetic material and common cellular structures. Perhaps there is only one sort of mind, with variations. Perhaps it's going a bit too far to imagine an octopus taking in interest in a football tournament, although maybe he did - after all, his predictions were more accurate than those of many people regarded as experts on the game. But without going this far, perhaps all thought is still much the same, and we can expect to have at least some insight into the minds of other creatures.
Then again, perhaps it isn't. We might think we understand octopuses because they have round heads and appear to act a bit like us. But if we are honest, we don't really know that. If they had a language, perhaps it would be impossible for us to translate into human language. Indeed, perhaps they do have one, and it is so different from ours we don't even recognise it as one. And what of bees? Perhaps their tiny brains just perform a limited version of the sorts of operations our massive ones do, restricted by their small number of neurons. But what if unlike humans, bees actually are telepathic? Then they could link their minds across the hive and engage in reasoning so complex it would make Albert Einstein look like a dummy. What if the complex dances are actually their least complex form of communication, and their incessant buzzing is actually a language of unimaginable beauty? It seems unlikely, but in the end we will never be totally sure.
As for trees and fungi - well, there is a strong probability that Peter Godfrey-Smith is right and they don't have minds at all. But if they did, would we be able to tell? What would life and thought look like for a tree, or a fungus?
Than are dreamt of in your philosophy.
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