It is very difficult to define consciousness. Sam Harris (quoting the philosopher Thomas Nagel) says that a creature is conscious if there is “something that it is like” to be this creature. It doesn’t seem that rocks have the complexity we associate with being aware, but we might be wrong. SeaTurtle01
Consciousness comes from having a brain. lisamarie3
Readers reply
However, if a rock were ever to choose to speak to me, as a scientist I would be receptive to the experience and excited to learn of its perspective. James Sonne
In the end, consciousness of rocks may be as much about semantics as about any scientific investigation. Does a rock have a subjective experience based on its unique place and its surroundings? That depends on how your consciousness chooses to interpret the words. I, for one, hold that neither consciousness nor free will exist and subscribe to an ultra-deterministic view of the reality we experience together as our particles are inextricably tied together from the origin of this universe, duly entangled for infinity.
Consciousness is measured by behavioural measures, neuro-imaging techniques or psychological measures, such as questionnaires. Note that all of these are themselves defined by “experience”, making experience synonymous with consciousness. As far as anybody knows, neuronal activity is required for experience. When rocks grow neurons, perhaps they will be conscious. Pablo Miller, Crozet, VA
Rocks have consciousness, it’s just that not all people have the capacity to engage with it. Richard Haynes
This question, posed on 2 April, was obviously asked a day late. Ted Green, Melbourne
As a geologist, no, rocks are not conscious. They are not aware of their being, nor do they make conscious decisions. But also as a geologist, who has spent a long time working on granites here in my home of Cornwall, there is something special about them. The granites define a certain type of landscape and therefore character of place. They come with their myths and legends and are said to whistle different ways in certain weathers. Generations of artists and writers have been inspired by the granites – look no further than Ithell Colquhoun’s The Living Stones. Could rocks be conscious? Maybe … Beth, Cornwall
I am the editor of the special topic area on the neuroanatomy of consciousness and the will, for MDPI’s NeuroSci journal.
The answer is they are, and here’s the proof:
The nature of those different experiences may be a starting point for understanding consciousness not as emergent aspects of our brains, but as fundamental elements of reality.
This is not a legitimate question since all things are conscious. In the eco-arts and science of green switch natureness, since forever and before, nature is its wordless attraction (love) to begin life and dance it into being. Attraction is conscious of what it is attracted to, otherwise it would not know what to bond or attach to, moment by moment and grow to be our spacetime universe this instant where all things are attached and happen all at once. This means that all things are alive and are conscious since we are. It’s our stories that subdivide things. Mike Cohen
One could argue that rocks are conscious. That even though they don’t have a brain or nerves they are somehow aware. To do this we can compare rocks to a couple of things. Plants don’t have a brain like animals, yet it has come to light recently that their root system is akin to a brain. Also, like rocks, many plants move slowly enough as to seem inanimate to us. However, in certain locations like Death Valley there are rocks that at least seem to move. Another thing we can compare rocks to are slime moulds. Slime moulds can solve mazes and learn despite being single-celled and without a brain.
Of course they are. Proof: the phrase “as dumb as a box of rocks”. Logically, it takes a certain level of intelligence to be dumb! Gobsheisse
Barney Rubble
We don’t know what consciousness is, or what causes it, or have any way of measuring it and therefore have no principled way of determining if any entity other is conscious or not. There are certain things that seem to correlate with consciousness – having a brain, reacting to stimuli, perceived similarity to ourselves, etc – but these don’t really help us because all arguments based on these apparent correlates are essentially circular.
Send new questions to nq@theguardian.com.
More readers’ answers here
I’ve just asked a rock. It showed no sign of either understanding the question or attempting a reply. So, no, I don’t think rocks are sentient. salamandertome
Short answer is to change word “conscious” to “aware”. Only objects that are alive, and have a metabolism, can be aware. Machines can register a surround and remember it, but they are not aware. They simulate consciousness but don’t possess it. Jack Klein
Although some alive things react to a stimulus, not all are able to make a choice as to how they react. My version of sentience would be having the capacity to make a choice in how they react or think. We have no evidence that rocks make choices. Squirls
If a scientist performs the double-slit experiment where photons are fired at background with or without an observer, photons seem to be able to tell whether they’re being observed. If everything is conscious even down to the subatomic level then it would make sense that rocks are conscious. Brock Lynch
It’s a no-brainer. Prof David C Sanders, Mortain-Bocage
Could rocks be conscious? Why are some things conscious and some not? Nigel J G Baptiste, Worcs
The philosophical debate surrounding consciousness has been ongoing for millennia, and in all likelihood will continue indefinitely. Views on the importance of a proposed immaterial mind and the material nature of the brain have been repeated and used to justify more practical philosophical arguments. Much of this debate depends on a person’s cultural background or scepticism more so than any scientific evidence. Plato argued that the soul is a separate, non-physical entity that is the seat of our thoughts; Descartes claimed that the pineal gland of the brain was the location of a mysterious junction between the nonphysical soul and the physical body. Our modern interpretation of scientific data describes consciousness as an epiphenomenon of brain processing. Sensory information is input into our biological system, the brain processes that information, and we output motive functions to react to the sensory information. Based on various classical neurological experiments that indicate a delay in our conscious decision-making and experience of the environment, consciousness is considered to be present in this middle processing step.
Even within ourselves as individuals, we can experience the same concepts in innumerable different manners. Take the case of a musical piece and the many ways it exists within our reality. One can hear one of Bach’s fugues, for instance, and process it as music which can elicit emotions;. one can analyse the music theory and experience the mastery of thought involved; we can also convert the sound waves into a visual representation. Similarly, Michelangelo’s David can be experienced visually for its representation of a human figure, or through X-ray crystallography to understand the atomic interactions of its substrate, or it can conjure moral narratives. Clearly, we exist not as a monolithic consciousness, because we experience the world in so many different ways.
While almost all of us are willing to extend that subjective experience to other people, the philosophical concept of solipsism argues that the only consciousness is our own brain, while other philosophies and religions claim that there is only one consciousness that we all share. Whether we can extend our subjective experience of consciousness in our brain to other structures – such as the delocalised neurons of insects, the intercellular organisation of plants or the crystalline structure of rocks – is something more difficult to answer definitively. Humans are wont to create categories with strict boundaries and make rules that govern our thinking based on those categorisations. Unfortunately, the natural world does not exist within categories and instead exists along a gradient with no clear demarcations.
Rocks could not be conscious. Some people will claim that this is because they lack some mysterious neurobiological or quantum property, or even a non-physical mind substance, that only conscious beings possess. But the explanation is simpler: unlike people and animals, rocks have no way to see, feel, think, or do, so they have nothing to be conscious of. David Silverman
I am an associate professor of philosophy at Durham University and leading proponent of panpsychism. We have been trying for several decades now to explain how consciousness could emerge from physical processes in the brain, and have got precisely nowhere. As a result, academic philosophers have of late been exploring an alternative approach to consciousness which turns this on its head: panpsychism. Instead of explaining consciousness in terms of matter, we account for the emergence of matter by postulating very simple forms of consciousness at the base of reality. This doesn’t entail that rocks are conscious, but it does mean that consciousness exists beyond the realm of biology. Philip Goff
For a truly scientific investigation of consciousness, I would argue that we must provide the space for other hypotheses among the many concepts yet unknown to science.
Researchers have devised rigorous experiments to identify statistical anomalies in human perception in the hopes of identifying unknown methods of non-material interactions that may point to a fundamental form of consciousness. These forms of consciousness may involve electromagnetic waves that interact at a distance, while some physicists may argue that the statistical models used to understand quantum physics allow for non-deterministic aspects of our reality. As an analogy, if neuroscience were to take the same approach as cosmologists, does there exist a fundamental “consciousness particle” like the “dark matter” and “dark energy”? Like the exchange of gluons within the nuclei of atoms that contribute to the mass that holds the universe together, is there a particle interaction that creates a subjective experience at the level of subatomic particles? An electron existing in the orbital of free hydrogen has a different experience of reality from an electron present in a covalent bond between two hydrogen nuclei. Is each electron in the universe experiencing something unique in its own corner of spacetime? Can this be said to be both “subjective” and “experiential”, and thus giving that electron a highly rudimentary form of consciousness? If so, is our consciousness the result of an additive function of the atomic structures and interactions that make up our bodies?
It is a basically unsolvable problem because it is a metaphysical one. We have no way of telling the difference between something that is conscious and something that isn’t. If we developed an embodied AI that in every way could act in a humanlike way, how could we ever tell the difference between something mimicking consciousness through a complex simulation of human behaviour but with no inner experience and something that behaved in the same way but did possess a subjective experience of the world? We can’t, not even in principle.
Ditto with rocks. The most we can say is that we have no reason to assume they are and therefore it seems more economic to assume they’re not. However, like a lot of assumptions that seem based on rock-hard common sense, that’s probably just something I tell myself to avoid going mad in a fit of Lovecraftian cosmic horror. I tell myself the people reading this are conscious for very much the same reason. QuesoManchego
I just asked my grandson. I didn’t get a response. seedysolipsist
According to Spinoza, if you ask a rock why it’s rolling down a hill, it’ll tell you it’s because it wants to. Wormlover
