Seemingly deceitful

“The Devil’s Trident” et al.

Simply put an illusion is something that is not real. But we most of us want to believe in things that science and reason tell us, by verifiably replicable experiments and observations, are not real; are “illusionary.” They say we see with our eyes, but let us be clear here, our eyes simply act as conduits to our brains, it is our brains that decipher and decide. For those fortunate enough not to be blind, we do like to be titillated by objects of beauty, panoramic views, the flickering of a fire, the waves rolling in and, optical illusions. The latter are a subject of much interest, writing in 1976, Coren et al. (1976, p. 129) pointed out that in the 120 years since Johann Joseph Oppel published the first systematic work on visual geometric illusions, “nearly a thousand papers have appeared that deal with distortions evoked by simple two-dimensional patterns of lines.” In the past 20 years with the aid of computers (to analyse) and social media (to share) the interest in optical illusions has grown further still (Alter, 2013; Hogenboom, 2015; Schultz, 2013). In this short essay I will discuss a number of such illusions, the way/s in which they trick the brain (alongside the human visual system) and the psychology behind them. But first I will discuss the workings of the eye and how it, like the human brain, is very susceptible to chicanery and trickery—to being deceived.

In the beholder’s eye

We know that the human eye works like a camera. When we look at something, light reflected from that thing enters the eyes through the pupil. Bizarrely it comes in upside down and this light and colour info is focused through the optical bits and bobs within the eye (see Appendix A). As Whitaker et al. (1996, p. 2957) point out in relation to the typical functioning of the human eye:

Judgment of the relative position of objects is an important feature of the human visual system. We seem able to perform this task effortlessly across spatial scales. Thus, whilst we can view two objects and estimate their separation, we are also aware of the relative position of internal features of the objects themselves.

However, the human eye, as with the human mind can easily be tricked. Optical illusions occur because our brains automatically try to interpret and make sense of what we see, usually they get things right, that Apple iPad ‘is’ an Apple iPad but, magicians and sellers of snake oil (and psychologists and visual artists) have long known eyes can be tricked because the human brain is partial to seeing myth as fact and fact as fake. Optical illusions fool our brains into seeing things which are there when they are not actually there or are not seemingly there when, in fact, they actually are.

Perception—what we think, what we think we see—is the interpretation of the things that enter our minds including via our eyes. They say beauty is in the eye of the beholder. Beauty is subjective. Therefore, the same object will not be seen as the same thing by any two people. As pointed out by Hogenboom (2015) Aristotle wrote that, “our senses can be trusted but they can be easily fooled.” This was in the context of him looking (not into Nietzsche’s abyss, but) into a waterfall for too long. He observed that, if we watch something moving quickly for too long, and then look at an inanimate object next to it — like the rocks beside a waterfall — they will appear to move in the opposite direction; a phenomena now classified as the “motion aftereffect” or, “the waterfall illusion.” Neuroscientists have argued that this can be explained by the fact that it takes a lot of energy and effort for the eye to compute fast moving and continually ‘forward’ moving objects so that when it suddenly switches to seeing a stationary object if over emphasises the lack of movement and moves the object slowly ‘backward’ (Hogenboom, 2015).

There is a theory attached to all of this and it is called the Centroid Hypothesis. It states that judgments of distance between visual objects are influenced by the brain’s computation of the “centroids of the luminance profiles of the objects” (Whitaker et al., 1996). Concerning the Devil’s Trident (see Appendix B), the Müller-Lyer arrows (see Appendix C), the Penrose triangle (see Appendix D) and similar illusions, the pattern of neural excitation evoked by contextual flank overlaps with that caused by the stimulus terminator, thereby leading (due to the shift of the centroid of summed excitation) to its perceptual displacement. The relative displacement of all stimulus terminators leads to misjudgement of distances between them; that is, the illusion occurs as a side effect due to necessarily low spatial resolution of the neural mechanism of assessment of the relative location of the visual objects.

The Devil’s Trident 🔱

Devil's Trident -- an optical illusion
Figure 1: “The Devil’s Trident,” Masterton and Kennedy (1975, p.107).

The Devil’s Trident (a.k.a., “The Impossible Trident”) was first noted in the academic press by an American psychologist—Donald Schster—who is said to have been inspired by an advert he saw in a magazine (Schuster, 1964). Accounts of the “Devil’s Trident”—see Appendix B—stress that the middle prong, “appears to be in two places at the same time” and that it involves, “incompatible surface depth cues linked as though they were compatible” (Masterton & Kennedy, 1975, p.107).

Knowledge of optical illusions is not a recent thing. Like all good things, we can go back to Ancient Greece to find initial thinking on the subject: Aristotle and the waterfall (as mentioned above). Indeed, as Bach and Poloschek (2006 p. 21) say, Plato also alerted us to the discrepancy between perception and reality in his “Allegory of the Cave.” Philosophers remain intrigued to this day. As Donaldson (2017) argues that impossible figures prove problematic for sense-data accounts of perception that contend that, corresponding to every visual human experience, there are mental objects (sense-data) that we are aware of—and that sense-data have the properties that the objects that our experiences tell us they do. The problem is that sense-data would have to be impossible objects … surely, impossible objects can’t exist!” There are other explanations. For example, illustrations like the Müller-Lyer arrows (see Appendix C) confuses the brain (in some cultures, according to Alter (2013), not all) and it overcompensates, “making the line appear bigger — as it would have to be in real life to produce those kinds of proportions” (Hogenboom, 2015).

Concluding remarks

To sum up, we can assume that we will never be able to suddenly see true reality with crystal clear clarity and 20/20 vision, be it the waterfall’s rock, the shadow play in the cave or the Devil’s Trident. But this is the magic of reality. This is something we should embrace and revere, not fear. Just because we do not know what lies within black holes or what exists beyond the edge of the universe does not mean we need to create myths to fill in the gaps and then dogmatically and religiously follow them (see Dawkins, 2011). Personally, I like that art can trick us it actually says to me we are human. Also, I feel that visual illusions are actually logical and explainable by reason and science: our brains have evolved to need to constantly predict what is about to happen so, illusions demonstrate our brain being logical and telling us what we should ‘typically’ see not what we rarely physically see.


Alter, A. (2013). Are These Lines the Same Height? Popular Science. Retrieved,

Bach, M &, Poloschek, C. (2006). Optical Illusions. Visual Neuroscience, 6(2), 20-21.

Coren, S., Girgus, J., Erlichman, H., &, Hakstian, A. (1976). An empirical taxonomy of visual illusions. Perception & psychophysics, 20(2), 129–137.

Dawkins, R. (2011). The Magic of Reality: How We Know What’s Really True. London: Bantam Press.

Donaldson, J. (2017). “Impossible Trident” in F. Macpherson (ed.), The Illusions Index. Retrieved,

Hogenboom, M. (2015). How your eyes trick your mind. BBC. Retrieved,

Howey, T. (2016). “How the eye works” Retrieved,

Masterton, B. &, Kennedy, J. (1975). Building the Devil’s Tuning Fork. Perception, 4(1), 107–109.

Schuster, D. H. (1964). A new ambiguous figure: A threestick clevis. The American Journal of Psychology, 77(4), 673.

Schultz, C. (2013). Are Optical Illusions Cultural? Smithsonian. Retrieved,

Whitaker, D., McGraw, P. V., Pacey, I., & Barrett, B. T. (1996). Centroid analysis predicts visual localization of first-and second-order stimuli. Vision Research, 36(18), 2957–2970.

Wikipedia (2020a). “Impossible trident.” Retrieved,

Wikipedia (2020b). “Müller-Lyer illusion.” Retrieved,

Wikipedia (2020c). “Penrose Triangle”. Retrieved,

— § —

Appendix A

How the Eye Works
(Howey, 2016)

— § —

Appendix B

Devil's Trident -- an optical illusion
Note: The devil’s trident (or ‘tuning fork’) is a drawing of an impossible to physically construct object. As articulated by Wikipedia (2020a), “it appears to have three cylindrical prongs at one end which then mysteriously transform into two rectangular prongs at the other end” (see also: Masterton & Kennedy, 1975, p.107).

— § —

Appendix C

Note: The Müller-Lyer illusion typically comprises of three arrows and we think the stems of these arrows are different lengths but, as the diagram shows, they are in fact the same length; as far as we know it was first devised by the German sociologist Franz Müller-Lyer in the late 1800s (Wikipedia, 2020b).

— § —

Appendix D

Impossibility in its purest form” is how the so-called Penrose Triangle is described. It is another of these object which can be drawn but cannot exist as a solid object -- just like this paper’s 'Devil’s Trident'
Note  “Impossibility in its purest form” is how the so-called Penrose Triangle is described. It is another of these object which can be drawn but cannot exist as a solid object (Wikipedia, 2020c) — just like this paper’s “Devil’s Trident” (see Appendix B, above).

Selfish {self.E}

The Century of the Self

The Century of the Self is a 2002 documentary made and produced by Adam Curtis. It considers the rise of psychoanalysis as a powerful mean of persuasion for both governments and multinational corporations. It consists of four parts:

01. — The Happiness Machine
02. — The Engineering of Consent
03. — The Policemen Inside our Heads
04. — People Sipping Wine

A while ago I wrote a post about how Instagram etc. is changing the way humans interact with the wilderness and sites of beauty and/or historic importance:



Wilderness Ruined

Today, I read a bit more about Instagram and how it seemingly deeply interferes with a great many of our psyches:

“Infinite scroll: life under Instagram”
by Dayna Tortorici (31 January, 2020)
The Guardian
“Why the New Instagram It Girl Spends All Her Time Alone”
by Dayna Tortorici (16 October, 2019)
The Atlantic
Tavi Gevinson’s Life on Instagram
by Lauren Starke (16 September, 2019)
New York Magazine

Here’s an interesting thing…

psyche means the human soul, mind, or spirit.
psychology means the scientific study of the mind.
Psyche [Ψυχη] however, is a name too. Only now did I know.

Psyche Abandoned, by Jacques Louis David (1795)
“Psyche Abandoned”
by Jacques-Louis David (1795)

^ look at her eyes, I mean, gaze into them and wonder the reason for why — my man’s eyes are a gorgeous green / my woman’s eyes are a beautiful brown — once you’ve done your wondering, I’ll tell you the reason for Psyche’s tear weary eyes. It is this: the flight of Cupid. Unfortunately, his sudden departure was something that she unintentionally caused. You see, despite having been forbidden as a mortal to look upon the god, Psyche could not resist discovering who her nighttime lover was and what he looked like (she knew well his sublime amorous moves and sweet wettening whispered words). So as Cupid slept, she gazed upon him by the light of an olive oil fueled lamp (Moby Dick wouldn’t be for another two millennia…). Mesmerised by his beauty, she accidentally spilled a drop or two of that warm frankincense incensed Kalamata oiive oil upon his naked torso. As a consequence, Cupid — for that was his name — woke and was compelled by God’s command to retreat back to the heavenly abode from whence he cometh.

Good thing is — I guess, yes — our dear Psyche became a god and lived happily ever after:

“Psyche Receiving Cupid’s First Kiss”
by François Gérard (1798)

I love

& I hate

Some may wonder how…

“How can it be both, Anna?”

Alas, I know not the why nor the how.

Anglophile? Me? You’re dreaming Darlin’



Stockholm syndrome

‘F’ me! ‘F’ me! ‘F’ me!
is this… is this…


Stockholm syndrome is a psychological response.

It occurs when hostages or abuse victims bond with their captors or abusers.

This psychological connection develops over the course of the days, weeks, months, or even years of captivity or abuse.



Love will tear us apart;
You’ve stolen my heart.
1) The second coming: Am I Dreaming?
2) Did I ruin you?
3) The second coming: Am I Dreaming?
4) Have you ruined me?
5) The second coming: Am I Dreaming?
6) A new beginning? The final ending?
Love will tear us apart;
You’ve stolen my heart.



Mary Ann Evans

[English | 1819–1880]

a.k.a., George Eliot

Mary Ann Evans was a philosopher, journalist and translator before she became a novelist. Her first book of stories was published in 1856. She led an unconventional life, co-editing the liberal journal Westminster Review for three years and living with the married man and philosopher George Henry Lewes. Her novels, in particular, Middlemarch, are acclaimed for their realism and psychological insights.

Only in the agony of parting do we look into the depths of love.

Mary Ann used the pen name George Eliot to write her novels because at that time in history female novelists were seen as only capable of being romantic authors. Thus, the argument goes, she wanted to be taken seriously as a writer, so felt that using a man’s name would afford her the credit.

What loneliness is more lonely than distrust?


— 1871, Edinburgh: William Blackwood & Sons.

Today it is widely considered to be the case that her novels are amongst the greatest works of English literature produced in the 19th c.

Middlemarch contains all of life: the rich and the poor, the conventional and the radical, literature and science, politics and romance, but above all it gives us a vision of what lies within the human heart, the roar on the other side of silence. In the story, Dorothea is bright, beautiful and rebellious. Lydgate is the ambitious new doctor in town. Both of them long to make a positive difference in the world. But their stories do not proceed as expected and both they, and the other inhabitants of Middlemarch, must struggle to reconcile themselves to their fates and find their places in the world.

Adam Bede

— 1859, Edinburgh: John Blackwood.

In this novel, the protagonist is Adam Bede, a wood worker, who is in love with the beautiful Hetty Sorrel, but unknown to him, he has a rival, in the local squire’s son Arthur Donnithorne. Hetty is soon attracted by Arthur’s seductive charm and they begin to meet in secret. The relationship is to have tragic consequences that reach far beyond the couple themselves…

The Mill on the Floss

— 1860, Edinburgh: William Blackwood & Sons.

In this novel, we meet Maggie Tulliver, a young lady who worships her brother Tom and is desperate to win the approval of her parents, but her passionate, wayward nature and her fierce intelligence bring her into constant conflict with her family. As she reaches adulthood, the clash between their expectations and her desires is painfully played out as she finds herself torn between her relationships with three very different men: her proud and stubborn brother; hunchbacked Tom Wakem, the son of her family’s worst enemy; and the charismatic but dangerous Stephen Guest. … choice-overload, right?


— 1863, London: Smith, Elder & Co.
This is said to be one of Eliot’s most ambitious and imaginative novels. It is set in Renaissance Florence during the turbulent years following the expulsion of the powerful Medici family during which the zealous religious reformer Savonarola rose to control the city. At its heart is Romola, the devoted daughter of a blind scholar, married to the clever but ultimately treacherous Tito whose duplicity in both love and politics threatens to destroy everything she values, and she must break away to find her own path in life.

Felix Holt, the Radical

— 1866, Edinburgh: William Blackwood & Sons.

The novel centres around a lady called Esther. When the young nobleman Harold Transome returns to England from the colonies with a self-made fortune, he scandalises the town of Treby Magna with his decision to stand for Parliament as a Radical. But after the idealistic Felix Holt also returns to the town, the difference between Harold’s opportunistic values and Holt’s profound beliefs becomes apparent. Forthright, brusque and driven by a firm desire to educate the working-class, Felix is at first viewed with suspicion but, as Esther discovers, his blunt words conceal both passion and deep integrity. Soon the romantic and over-refined Esther finds herself overwhelmed by a heart-wrenching decision: whether to choose Transome or Holt… ch- ch- choices — again 😦

It is never too late to be what you might have been.

The Guardian view on George Eliot: a novelist for now
— Editorial
“It is 200 years since the birth of George Eliot, and her artistic virtues – humanity, honesty, seriousness – are more necessary than ever…”

Also, I wanna introduce to A.S. Byatt who has written a lot about George Eliot, is a well regarded literary critique (heart) and is a novelist in her own right and is, according to one essayist, “a gifted observer, able to discern the exact but minor details that bring whole worlds into being.”

It says ‘Romance’ and in some ways it is, but in others it is not…

Possession is not just a novel; it’s a collection of poetry, letters, journals and diaries, each with their own distinct voice. A tour de force of prose-wring skill, beyond the usual demands of fiction, written by a literary ventriloquist. The novel begins in the Reading Room in the London Library. Part-time research assistant Roland Michell, finds letters hidden inside a book. They were written by celebrated Victorian poet Randolph Henry Ash to Cristobel LaMotte, a lesser-known writer, suggesting an adulterous affair…

📙 The Magic of Reality

O. J. ( as in, “Oh, Jay!” )

This book really and truly fascinated me:

The examples and illustrations are mind opening and mind blowing, respectively.

p. 96

Richard Dawkins (see full profile here) is an English evolutionary biologist, author and professor at Oxford University. His seminal work The Selfish Gene (1976), popularised the gene-centred view of evolution and introduced the term meme. Here are a few extracts from The Magic of Reality that I feel it is okay to share as editable .pdf files:

pp. 12-13 from ‘The Magic of Reality’ (Dawkins, 2011)

pp. 32-52 from ‘The Magic of Reality’ (Dawkins, 2011)

pp. 118-139 from ‘The Magic of Reality’ (Dawkins, 2011)

pp. 246-265 from ‘The Magic of Reality’ (Dawkins, 2011)