If the world we observe is just our brain’s interpretation of the electrochemical signals it receives from our eyes, what is the world actually like?
Sutton Coldfield, West Midlands, UK
The short answer is that we don’t really know.
What we see is the brain’s interpretation of electrochemical signals produced when light hits the retina. There is no reason to assume that our perception is the definitive one.
Asking what reality looks like independently of any observer may therefore be a little like asking what a symphony sounds like to something that cannot hear. There are pressure waves in the air, but “the sound” is the experience produced when an auditory system interacts with those waves. What something looks like is quite literally in the eye of the beholder: bats construct a world largely through echolocation, while birds and bees see wavelengths that are invisible to us.
Even touch is an experience. A table feels solid, but, in one sense, atoms are almost empty space. What stops your hand passing through the table is a combination of electromagnetic forces and quantum effects, including the Pauli exclusion principle. The physical forces are real; feeling something solid is how we experience them.
The qualities of the universe may arise only when the physical world interacts with something able to experience it
So, perhaps asking what the universe actually “looks like” is the wrong question. It may not intrinsically look, sound or feel like anything. These qualities may arise only when the physical world interacts with something capable of experiencing it.
This leads to the deeper problem of consciousness. Everything we know about reality ultimately comes to us through conscious experience. We can never step outside consciousness to compare our perception with an objective version of reality, if one exists.
Taken to its extreme, this leads to solipsism: the idea that the only thing we can know with absolute certainty is that experience exists. We have very good reasons to believe that an external world and other minds exist, but ultimately both are inferred from experience.
That doesn’t mean the universe disappears when nobody is looking. But it leaves a profound question. Does consciousness simply emerge from the physical processes taking place in our brains, or is it somehow a fundamental feature of reality?
Coonabarabran, New South Wales, Australia
Many people already accept that there are two worlds – the simulation in our brain and the real one. The simulation is based on our sensory inputs. Everyone will have a unique experience of the world due to several factors, including our mental and emotional state.
But what is the real world actually like, free from our human bias? I suspect that the real world takes on a particular reality only when imposed by an observer. This is a world of force fields and transient states, things that we may overlook in our simulated world. In the real world, nothing has a fixed boundary.
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