When Reality Is a Shared Hallucination: Seeing, Believing, and the Art in Between
Is reality real? And how does this ambiguity affect our perception of art?
“Reality,” neuroscientist Anil Seth suggests, “is a controlled hallucination — and when we agree about our hallucinations, that’s what we call reality.”
— TED Talk, Your brain hallucinates your conscious reality, 2017
Each person lives within a private construction of the world, stabilized only through consensus. Perception becomes a fragile contract between the senses and society — a negotiation that allows communication, not a guarantee of truth.
Reality, in this view, is not something discovered, but continually co-authored by billions of perceptual systems trying to make sense of light, shape, and sound.
If this sounds startlingly modern, it also echoes ancient philosophy. Long before fMRI scans or predictive-coding models, Plato imagined the cave — a dark chamber where prisoners, chained since birth, mistake shadows on a wall for reality itself. What they call truth is merely the play of light cast by unseen objects. Only the philosopher who breaks free and turns toward the fire—and eventually, the sun—discovers that the world of appearances is but a dim imitation of the real.
Today’s neuroscientists describe something remarkably similar: the “neural theater” in which the brain projects its internal model of the world. What we see are not the things themselves, but patterns of light reconstructed, interpreted, and filtered through expectation. Where Plato located illusion in the cave’s darkness, modern science finds it in the cortex — yet the metaphor endures. We, too, live among shadows, convinced of their solidity because our senses agree upon them.
The Fragility of Vision
Even at its most biological level, vision is selective. Humans perceive only a thin band of the electromagnetic spectrum — roughly 380 to 740 nanometers in wavelength. Everything beyond it — infrared, ultraviolet, X-ray, gamma, radio — exists, yet remains invisible to human eyes.
Other species inhabit richer spectra:
- Birds and bees detect ultraviolet.
- Pit vipers sense infrared.
- Mantis shrimps perceive up to sixteen color channels compared to the human three.
Each organism lives within its own translation of the same physical world. If humans could perceive all wavelengths, both the world — and art — would appear utterly different. What we now call “real” might suddenly shimmer with unseen gradations.
“Our visual systems take what is essentially an impoverished two-dimensional pattern of light falling on the retina and reconstruct it into an experience of depth, texture, and meaning.”
— Margaret Livingstone, Vision and Art: The Biology of Seeing (2002)
Vision, then, is not a window but a filter — an exquisite simplification that allows survival within overwhelming complexity.
Theories We See
Cognitive scientist Donald Hoffman, in The Case Against Reality: Why Evolution Hid the Truth from Our Eyes (2019), extends this idea radically. He argues that perception evolved not for accuracy but for utility. The brain constructs a simplified “interface”, hiding objective reality behind icons useful for survival:
How can our senses be useful — how can they keep us alive— if they don't tell us the truth about objective reality? A metaphor can help our intuitions.
Suppose you're writing an email, and the icon for its file is blue, rectangular, and in the center of your desktop. Does this mean that the file itself is blue, rectangular, and in the center of your computer? Of course not. The color of the icon is not the color of the file. Files have no color. The shape and position of the icon are not the true shape and position of the file. In fact, the language of shape, position, and color cannot describe computer files.
The purpose of a desktop interface is not to show you the "truth" of the computer-where "truth," in this metaphor, refers to circuits, voltages, and layers of software. Rather, the purpose of an interface is to hide the "truth" and to show simple graphics that help you perform useful tasks such as crafting emails and editing photos. If you had to toggle voltages to craft an email, your friends would never hear from you.
That is what evolution has done. It has endowed us with senses that hide the truth and display the simple icons we need to survive long enough to raise offspring.
— Donald Hoffman, in The Case Against Reality: Why Evolution Hid the Truth from Our Eyes (2019)
This recalls Descartes’ doubt: if the senses deceive, what can be known with certainty? Only the act of thinking itself — cogito, ergo sum. Yet modern neuroscience suggests that even thought depends on perception. The very act of being may rely on the brain’s capacity to hallucinate coherently.
Reality does not precede perception — it emerges through it.
Filters, Biases, and the Color of Expectation
Perception is also cultural.
Across languages and epochs, societies have carved the color spectrum differently. Ancient Greek texts rarely mention blue; Homer’s “wine-dark sea” describes the sky in metallic hues. As linguist Guy Deutscher notes, early languages lacked a discrete term for blue. The Greeks saw the color — they simply did not name it as we do.
Contemporary linguistics confirms this relativity: what one culture separates as “blue” and “green,” another merges into a single hue. Color becomes both physics and linguistic agreement — a social artifact layered upon biology.
“The expectations come before the information is even received… constraining the way the brain’s lower areas process information.”
— Bianca Bosker, Get the Picture, (2024)
Expectation precedes perception; the mind predicts before it observes.
Seeing is a negotiation between what the world offers and what the brain anticipates.
Philosopher Nelson Goodman called these shared perceptual codes “ways of worldmaking.” We never perceive the world as it is, only as our symbolic systems allow. Each culture’s “reality” is an aesthetic consensus — a collectively edited illusion.
From Human Eyes to Machine Vision
Cameras and neural networks now extend this negotiation. They perceive wavelengths we cannot, analysing millions of hues and contrasts. Yet their perception remains tethered to the datasets provided by humans — the same biases of framing and culture.
Machine vision inherits human blindness in new forms. Its gaze is mathematically precise but semantically inherited. Algorithms can register wavelengths invisible to us, but they cannot escape the symbolic frameworks we designed.
Artificial vision, then, magnifies the human condition: the tension between seeing and interpreting, between data and meaning.
Art and the Reality of Seeing
Art operates precisely within this ambiguity.
It is both a manipulation of perception and a meditation on its limits.
Painters from the Impressionists to the Optical Art movement have exploited how the brain constructs reality — Monet’s shifting light, Albers’ nested squares, Turrell’s luminous chambers. All reveal that vision is unstable, contingent on context and expectation.
“Art is the biology of seeing made visible.”
— Margaret Livingstone
If reality is a consensus of hallucinations, art is a deliberate disturbance of that consensus — a lucid experiment at the edge of the visible.
The Hallucination That Knows Itself
If perception is a fiction sustained by biology, then art is that fiction made self-aware.
A Turrell chamber or an Eliasson installation doesn’t depict the world; it recreates the act of seeing, making the viewer both participant and witness to their own hallucination.
Conclusion: The Lucid Hallucination
So, is reality real?
Only insofar as minds agree upon their hallucinations. Reality is a negotiation among billions of perceptual systems, each translating a fragment of the spectrum — electromagnetic and conceptual.
How does this ambiguity affect art?
It reveals art as both reflection and experiment within those hallucinations.
Art becomes the deliberate construction of new perceptual conventions — a playground for testing the edges of the visible and the imaginable.
If we could see ultraviolet and infrared, every gallery would bloom with unseen layers. Yet even within our narrow corridor of vision, artists have found infinite worlds.
Art does not free us from illusion; it teaches us to see lucidly within it.
Between the hallucination of the world and the agreement of the many, Art reminds us that perception is never passive — it is creation. It is the hallucination we have chosen to share.