Psychology

Relative Size Illusions

Gianni Sarcone

Here are two relative size illusions I described back in 1997 and 2013.

The first, called Sarcone’s Crosses, challenges classic illusions like the Ebbinghaus illusion (Titchener Circles, 1898) and the Obonai square illusion (1954). It features a cross (the test shape) surrounded by squares of different sizes.

As shown in Fig. 1.a, 1.b, and 1.c, the three blue crosses are all the same size — yet the one on the left (Fig. 1.a) appears larger. Surprisingly, the illusion still works even when smaller squares completely cover the cross (Fig. 1.c).

So, the size of surrounding shapes doesn’t always dictate how we perceive the central one.

In the second illusion (Fig. 2.a and 2.b), due to assimilation, the red diagonal inside the larger ellipse seems longer — but the blue line is actually the longest.

Perception loves to play tricks on us.

sarcone's relative sizze illusions

You can explore more of my illusions and visual inventions on my official site: giannisarcone.com

A Hidden Time Machine

Gianni Sarcone

We all carry within us a time machine—hidden in plain sight, right in the middle of our face. It may sound unlikely, but the NOSE is the only sensory organ capable of transporting us into the past without our even realizing it.

Our sense of smell activates memories like no other. A single scent can unlock a precise moment from childhood or early adulthood: the fragrance of oranges at Christmastime, melting snow during your first school field trip in winter, the scent of your sweetheart’s sweater the day you met, your grandmother’s simmering tomato sauce during Sunday lunches, the waxed floor of your grandparents’ house, school glue in primary class, the sunscreen of beachside summers, old book ink in the town library, the leather of your first satchel, or the aroma of fresh coffee at dawn when everyone else was still asleep…

The nose is a powerful trigger for nostalgia because the olfactory bulb, where smells are processed, is directly connected to the limbic system—the brain’s emotional and memory center. This close link allows smells to summon vivid memories, often with startling clarity, and sometimes, with them, an unexpected flood of emotions.

Each smell opens a door to a suspended instant—fragile, vivid. It’s an inward journey to a hidden past, a place buried deep, that suddenly bursts forth like a firework of nostalgia.

Each of us holds a palette of scents capable of bringing us back—suddenly, vividly—to a time that’s gone. Mine carries rustic, earthy tones: my maternal grandparents were farmers, and I spent much of my early childhood with them in the mountains of Irpinia.

I remember the sticky perfume of freshly harvested tobacco leaves, the white film of yeast clinging to wine grapes, the wild asparagus gathered by riverbanks, the unmistakable sweet scent of the ceuze—what we called mulberries in dialect—and the zenzifero, a local mint that gave ricotta ravioli its delicate fragrance…

I doubt I’ll ever stumble across those long-lost smells again—or perhaps they’re just dormant, waiting. But if they do return, that would be the most beautiful time travel I could ever hope for.

And you? What scents carry you away to other times, other worlds?

smell memory, nose

Smelling the Color 9: When Numbers Take Shape and Color

Gianni Sarcone

In English, the expression to smell the color 9 describes something completely impossible…

And yet, some people have the unusual ability to mentally visualize colors or spatial patterns when thinking about units of time—or more broadly, numbers. This phenomenon, known as synesthesia (from the Greek syn, “together”, and aisthēsis, “sensation”), occurs when stimulation of one sense involuntarily triggers sensations in another. It’s not a figure of speech—these perceptions feel very real to those who experience them.

The first documented case in medical literature appeared in 1710. Dr. John Thomas Woolhouse (1650–1734), an ophthalmologist to King James II of England, reported a blind young man who claimed he could perceive colors induced by sounds.

Neuroscientist Vilayanur S. Ramachandran and his team at the University of California, San Diego, observed that the most common form of synesthesia links “graphemes“—letters or numbers—to specific colors. Since my work bridges art and mathematics, I’ll focus here on number-based synesthesia.

People who experience synesthesia in its pure form are relatively few. However, many report strikingly similar associations between numbers and colors or spatial layouts, suggesting these perceptions aren’t just products of imagination or attention-seeking. For example, number–form synesthesia may result from cross-activation between brain regions in the parietal lobe that handle numerical and spatial processing. In contrast, number–color synesthesia likely stems from an overabundance of connections between adjacent areas that interfere with each other when triggered (see fig. 1 below).

brain synesthesia

Figures 2 and 3 illustrate common synesthetic patterns—either as color associations (fig. 2) or spatial arrangements (fig. 3, based on observations by Sir Francis Galton). Statistically, people often associate the digits 0 or 1—and sometimes 8 or 9—with black or white. Yellow, red, and blue are typically linked to smaller digits like 2, 3, or 4, while brown, purple, and gray tend to be tied to larger ones like 6, 7, or 8. Curiously, it’s not the idea of the number but the visual form of the digit that seems to trigger the sensation. For instance, when the number 5 is shown as the Roman numeral V, many synesthetes report no color at all.

color number synesthesia

And you—do you see numbers in color or arranged in space? Feel free to share your synesthetic experiences with me.

Misdirection → Illusion → Aha! Moment…

Gianni Sarcone

How misdirection, illusion, and wonder shape my creative process.

The path from misdirection to revelation is at the heart of how illusion and wonder spark insight. Misdirection steers our attention—often subtly—away from what truly matters. It disrupts our expectations, creating a gap between what we see and what is. Within that gap lies the illusion: a crafted discrepancy, a visual or cognitive sleight-of-hand that unsettles our perception.

But the magic doesn’t end there. When the illusion is cracked—when the mind shifts, recalibrates, and sees—the famous Aha! moment erupts. That flash of understanding isn’t just delightful; it’s deeply educational. It rewires how we interpret the world.

This sequence—misdirection, illusion, revelation—mirrors the creative process itself. It shows how confusion, when carefully designed, can be a gateway to clarity. In the right hands, illusion is not deception—it’s a tool to awaken curiosity, stretch perception, and provoke insight. Wonder, in this sense, becomes a powerful cognitive catalyst.

That’s why my art and, I believe, my writing, revolve around this sense of wonder—arguably the most direct and playful route to that pleasurable, often conflicting moment of insight: the sudden discovery of something previously unknown.

The Word: From Incantation to Influence

Gianni Sarcone

In the beginning, whether real or invented, certain words—many from a distant past—formed a bridge between humans and the great Mystery. One such word that survived the ages, still cloaked in a strange aura of power, is Abracadabra. Even today, magicians use it to conjure effect, echoing its ancient weight.

Originally, Abracadabra wasn’t just theatrical. It was an apotropaic charm—spoken or inscribed to ward off harm. The earliest record, from the 2nd century CE in a medical treatise by Serenus Sammonicus, describes it as a remedy for fever. Written in a tapering triangle, the word visually dissolved with each line, symbolizing the illness retreating. Its origins are uncertain. Some link it to Aramaic or Hebrew—“I create as I speak” (אברא כדברא). Others see it as a coded sequence from the Greek alphabet (ΑΒΓΔ), or a variant of another potent name: Abraxas.

An incantation born of another—what a journey through a world woven in magic.

Abraxas (Greek: ἀβραξάς), central to the Gnostic teachings of Basilides, named a powerful being ruling over 365 heavens. Engraved on amulets, Abraxas was thought to hold innate power. These stones, often cited in magical texts, show a belief system where sound and symbol merged—where the right word could invoke protection, healing, or cosmic order. Its earlier spelling, Abrasax, likely morphed through transliteration. With seven letters, the name was also tied to the seven classical planets, deepening its cosmic charge. Whatever its true roots, one idea persists: properly arranged, words carry force.

Across time, this belief shifted but never vanished. Ancient incantations gave way to new forms of verbal power.

Antiphon of Athens (5th century BCE) stripped speech of ritual but kept its essence. Considered a forerunner of psychotherapy, he used dialogue to ease emotional suffering. His method wasn’t mystical—it was precise, rooted in rhetoric and clarity. Where once words summoned the divine, now they served insight and balance.

Language, even without the trappings of magic, remains transformative. In the 20th century, thinkers like Paul Watzlawick showed how communication doesn’t just reflect our world—it shapes it. A change in phrasing can shift perception. A word can open or close a mind.

From Abraxas to Abracadabra, from spell to speech, the thread continues: words influence, connect, heal. What began as incantation lives on as conversation—still crafting reality, still carrying power.

B.U.T. – Bridging Unlikely Thoughts

Gianni Sarcone

Ah, the infamous “BUT“! The semiologist in me would have a field day with this little word. It’s like the ultimate plot twist in a sentence—an entire world of contradiction wrapped in just three letters. It’s the “Dr. Jekyll and Mr. Hyde” of conjunctions: on one hand, it tries to introduce a new idea, and on the other, it erases everything said before, as if it were all just a warm-up.
As a historian, I’d argue it’s the “philosopher’s stone” of language. A single “BUT” has the power to change history—like when someone says, “I’m not sexist, BUT women just aren’t good at math.” And then—BAM!—history is rewritten in a very particular shade of awkward.
The comedy gold lies in the absurdity of it all. It’s a linguistic loophole, designed to create just enough space for a “disclaimer” while conveniently ignoring any of its consequences. Call it the punctuation equivalent of “I have a friend who…” or “No offense, but…”—it sets you up for everything that follows, no matter how absurd!

The Many Flavors of Absence

Gianni Sarcone

A guy walks into a bar and asks for a coffee without cream. The bartender replies, “Sorry, we’re out of cream—how about a coffee without milk instead?” 

It’s a simple joke, but it highlights something curious: absence has weight. Psychologically, a coffee without cream doesn’t feel quite the same as a coffee without milk. 

Now, let’s take it a step further. Is the absence of a loved one the same as the absence of a random stranger? Of course not. Absence isn’t just a void—it carries the shape of what’s missing. 

The ancient Greeks had a word for this: steresis (στερήσις), the idea that everything is defined by both what is present and what is absent. Zen philosophy explores a similar concept with mu (無), suggesting that sometimes, absence is a kind of presence in itself. 

So next time you order a coffee without cream, pause for a second—what is it you really don’t want to be in there?

The Architecture of Light

Gianni Sarcone

Colors, though fundamentally phenomena of light, are not merely superficial aspects of perception. They play a structural role in organizing visual elements. For example, applying contrasting colors to a series of repetitive graphic patterns—while varying their distribution—can dramatically alter how they are perceived. This demonstrates how color is not just an embellishment but an active force in shaping visual reality.


As Goethe put it, “Colors are the deeds and sufferings of light.” More than a sensory experience, they influence our perception of space, depth, and meaning, revealing the intricate dialogue between vision and cognition.

🔍 Explore more about the illusion of colors.

Reflections of the Self

Gianni Sarcone

The mirror stage, conceptualized by Lacan, occurs in humans between six and eighteen months of age. It is the moment when a child perceives a unified image of their body and recognizes themselves in the mirror—a process rooted in the imaginary dimension—often accompanied by a sense of jubilation. This stage marks the emergence of narcissistic identification with the self.

But what about animals? Do they recognize themselves as a tangible entity in a mirror, or does their reflection remain an enigma to them? Research suggests that self-recognition in a mirror is rare in the animal kingdom. While species such as great apes, dolphins, elephants, and some birds—like magpies—can pass the mirror test, most animals either ignore their reflection or react as if encountering another individual. This highlights fundamental differences in self-awareness across species.

Do Animals Recognize Themselves in a Mirror?

Puzzling Colors: Red Between the Lines

Gianni Sarcone

Colors are not as fixed as they seem. The red you see might not be the same red someone else perceives. Your brain constantly interprets colors based on their surroundings, which can lead to surprising illusions.

Take this experiment inspired by the Munker-White effect: all the gray bars in the striped patterns are actually the same shade. Yet, next to blue lines, they appear bluish; beside mixed colors, they seem to shift tones. This is known as color assimilation—where a color takes on the influence of its neighbors.

The same illusion explains simultaneous brightness contrast. In the wine-pouring examples below, the liquid seems to change color in the glass. But actually, the red remains unchanged.

Here’s a simple animated variant of my project: Hard to believe, but the flow of wine stays the same shade of red all the way—from the bottle’s neck, through the pour, and even inside the glass. It’s only your perception that changes!

Even more striking—when cyan lines replace black ones, the liquid pouring from the bottle is actually gray from start to finish, yet it appears to turn into red wine in the glass. In reality, the red is just an illusion—your brain fills in the missing color where none exists.

🔴 See it for yourself! Fine art prints of my color experiments are available here:
👉 https://www.redbubble.com/shop/ap/166097393

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