Mary Jane’s Last Dance

For an album of greatest hits Tom Petty wrote yet another greatest hit.

For his 1993 album Greatest Hits Tom Petty was asked to record two new songs. The album already included 16 of his best songs from the previous 17 years, but MCA wanted a few bonus songs (as was the style at the time, to include some bonus material on compilation albums). Petty was not interested in having to write new material so he dug around through some old song ideas. Producer Rick Rubin picked a fragment of a song that had a good riff and potential to be a good song.

Petty took the riff he created 5-ish years earlier, and wrote Mary Jane’s Last Dance. The song was a hit and peaked around #14 on the Billboard Hot 100. So, when pressured to write a new song for an album full of his greatest hits, Tom Petty wrote a song that itself became another one of his greatest hits.

Kim Basinger, dead woman

A driver of the song’s commercial success was the accompanying music video. The video (which has nothing to do with the lyrics) has Petty playing a morgue assistant who becomes infatuated with a beautiful dead woman (played by Kim Basinger). He takes her home, he tries to dance with her, he props her up at the dinner table, but eventually he release her body into the waves of the ocean.

Talent to Spare

It’s hard enough to write one hit song let alone a hit song to accompany your other hit songs. While Petty may have written the song under duress, it’s a testament to his talent that he still wrote one of his best songs. Regarding Mary Jane’s Last Dance, Petty later said “I complained about that [song] so much … I’m really glad I did it now.”

the Barkley Marathons

The Barkley Marathons is an ultramarathon that is “set up for you to fail.”

For runners who find the traditional marathon distance of 26.2 miles not challenging enough, there is the ultramarathon. An ultramarathon is any race beyond 26.2 miles. Some are a set distance while others are a set time with runners going as many miles as they can within that time.

While all ultras are grueling, some are particularly noteworthy. The Badwater 135 is a 135 mile race going from the lowest point in California to the base of the highest, from Death Valley to the trailhead of Mt. Whitney. The Marathon des Sables (The Marathon of the Sands) is 150 miles of running in the Moroccan portion of the Sahara Desert where runners have to carry their own food & water. Part of the entrance fee also covers the repatriation of your corpse should you die. While there is no real ranking of the most difficult ultras, one that makes every list is the Barkley Marathons.

Runners headed down “Rat Jaw”, from the 2017 Barkley.

The Barkley

Set in the rugged hills of Eastern Tennessee, the Barkley Marathons is an annual race where 35 to 40 runners look to run 100+ miles in less than 60 hours. The course is 5 laps around the woods of Frozen Head State Park, up and down the hills of mostly unmarked trails. There is no electronic tracking and participants are not allowed any GPS devices, leaving runners to wayfind by map & compass. To prove you’ve made each full lap you find books in the woods at designated places and tear out the page corresponding to your running bib number. Because of the many hills the total cumulative elevation gain is around 54,000 feet, or 2 Mount Everests in 3 days.

The Barkley Marathons is universally considered one of the hardest races in the world. Most people who start never finish. The temperature changes, the distance, the lack of sleep (the race runs day & night), and the terrain (the hills, the thorns, the uneven ground) all work against you. Founded in 1986 by Gary “Lazarus Lake” Cantrell, more than half of the races have ended with no-one completing the course. As of 2021 the full race has only been completed 18 times by 15 runners – around a 1.3% completion rate.

The idea for the race came from the 1977 escape of James Earl Ray from the Brushy Mountain State Penitentiary (which is located beside Frozen Head State Park). In 55 hours Ray only made it 8 miles from jail because of the terrain. Cantrell felt that in 55 hours he should have been able to make it 100 miles, and so began the Barkley Marathons.

The Barkley Marathons founder “Lazarus Lake”

How and why would you do this?

The registration process to enter the Barkley is a secret. There is no website. Entrants pay a $1.60 entry fee and write an essay on why they should be allowed to participate. First time participants are also required to bring their license plate with them which Cantrell strings together and hangs like a curtain at the starting area. For repeat participants Cantrell requests some article of new clothes that he is in need of (flannel shirts, socks, etc.). Each year one person is allowed to participate who Cantrell knows will almost certainly fail, the “human sacrifice.” This person is given bib number 1.

Why would someone do this? As with running a regular 26.2 mile marathon, or any sort of endurance challenge, participants want to know what they are capable of. For most people winning isn’t the goal (or even an option). You’re in competition with yourself more so than with the other runners. People want to see, when really put to the test, what can they accomplish? What are they made of? The Barkley Marathons sits at the edge of impossibility, giving participants the rare chance to learn about themselves and see what they’re made of.

“If you’re going to face a real challenge it has to be a real challenge. You can’t accomplish anything without the possibility of failure.”

GARY “LAZARUS LAKE” CANTRELL, Barkley Marathons founder

The excellent documentary The Barkley Marathons: The Race That Eats Its Young chronicles the 2012 race.

Zebra Domestication

Zebras have too many characteristics that make them poor candidates for domestication.

Zebras are in the genus Equus, the same genus as horses and donkeys. There are three species of zebras, which roam wild in grasslands, woodlands, and mountainous areas of southern Africa. Given that their Equus cousins (horses & donkeys) have been domesticated, it is logical to think that zebras could also be similarly domesticated. However, zebras have some characteristics that make them poor candidates for domestication.

Domestication

Domestication of a wild species has to be worth the effort (is the juice worth the squeeze?). If the costs are too great then there’s little point in doing it.

Some of the keys to domestication are:
Diet – Is their food inexpensive? are they picky eaters?
Growth rate – Will they grow big quickly?
Reproduction – Will they reproduce in captivity?
Social hierarchy – Do they naturally form a chain of command? Will they take orders from a human?
Fight or flight response – When spooked what do they do?
Temperament – How nice are they in general?

As it turns out, zebras are not the most happy-go-lucky animals.

Horses and donkeys came from Eurasia which had relatively few apex predators and so these animals tend to be fairly docile. Zebras however were/are surrounded by lions and other very dangerous predators. As such zebras adapted to survive by any means necessary. This survival instinct means that sometimes a zebra will flee from a threat, but it also means that they’re ready to fight. They can kick so hard they’re able to break a lion’s jaw. Zebras are not flashy looking donkeys – they bite, they kick, and they tend to see humans as a threat. All of this adds up to why zebras have not been domesticated. They aren’t people-friendly, they don’t want to be managed, and they don’t want to do your work.

Attempts have been made

This is not to say people haven’t tried. As white settlers of Africa encountered zebras they frequently wondered why the local people had’t already domesticate them. It certainly would have made matters easier for the colonizers since zebras were already resistant to tsetse flies, they wouldn’t have to import horses, etc. The Dutch Boers tried but quickly learned that zebras didn’t want to be domesticated.

Sometimes you see a few zebras that have been tamed, but a few tame zebras isn’t the same as domesticating the species. Baron Lionel Walter de Rothschild of Victorian England had a carriage drawn by four tamed zebras that he would ride through London. He wanted to show that zebras could be tamed, but given that we never saw many other carriages pulled by zebras, he may have proved the opposite.

In general, zebras do not respond well to attempts at domestication — they don’t have the temperament and at this point there is no need.

Added info: While the domestication of zebras has never worked, the crossbreeding of them has. Some zebra hybrids include: Zorse (horse + zebra) and Zonkey (donkey + zebra).

Irish “Pub In A Box”

As part of a Guinness marketing effort in the early 1990s, thousands of Irish pubs around the world have been built using standardized design templates.

Recognized around the world, the Irish pub is one of the most well-known Irish cultural exports – and where there’s an Irish pub there’s usually Guinness. In the 1980s Guinness began to track the causal relationship between new Irish pubs and regional increases in Guinness beer sales. As new pubs opened, Guinness sales went up. If Guinness could help create more Irish pubs then they could also increase their own revenue.

Ahead of the 1990 World Cup in Italy, Guinness sales representatives traveled around Italy meeting with potential Italian business partners with the goal of opening Irish pubs. Their pitch was built around revenue generation and how Irish pubs have a more profitable beverage-to-food ratio than most other bars. From January to June of 1990 Italy opened 58 Irish pubs, welcoming Irish soccer fans and drinkers of all kinds. However, the critical factor to revenue generation was that these pubs needed to appear authentic – enter the “pub in a box”. 

Pub in a Box

Successful Irish pubs outside of Ireland have the look & feel of the real thing. As part of their expansion effort Guinness assembled a team to analyze, quantify, & document the seemingly ineffable essence of the Irish pub. The Irish Pub Concept helped determine the critical success factors to operating an Irish pub. Chief among these factors is visual authenticity.

Founded in 1990, the Irish Pub Company of Dublin was one of the first companies to offer “authentic” Irish pubs for export. Instead of doing all of the work yourself they’ll take your dimensions and design, manufacture, and ship all of the necessary materials to you. Do you want the rural Irish pub style or the Victorian? Maybe you want the general “Celtic” style. They offer a variety of prepackaged pub types that come complete with all the knickknacks for the walls. To date they have designed & shipped over 2,000 pubs to more than 50 countries.

Fadó in Chicago, designed by the Irish Pub Company in their “Celtic” style.
Mandy’s Apothecary in Moscow, designed by the Irish Pub Company in their “Shop” style.

The Irish Pub Co. isn’t alone. Ól Irish Pubs and GGD Global also offer to design & ship you a “pub in a box”. This Disney-ized packaging of Irish culture is not without criticism. For one it raises questions of authenticity. It’s true these are pubs that have been designed & manufactured in Ireland. However, it’s difficult to claim authenticity when your pub has a fake Irish country store as part of the decor. Instead of organically collecting meaningful mementos for your bar, these superficial design packages ship all the rusty farm equipment, dusty old bottles, and framed photos of strangers you need to give the illusion of authenticity. Why take years cultivating a unique local flavor when you can just throw up a portrait of Michael Collins or the Molly Maguires?

An additional criticism is of Guinness for helping to bring these “pub in a box” bars into existence. Established Irish bars were expected to keep serving Guinness beer while the Guinness company was busy creating additional local competition. Beginning in the early ‘90s some bars boycotted and stopped serving Guinness. McGillin’s Olde Ale House of Philadelphia still does not serve Guinness as a result of the “pub in a box” fallout with Guinness.

The Wild Rover in Barcelona features framed photos of random Irish people, used purely as decoration.

Better than nothing

To many customers the ambiance that these cookie-cutter bars generate is all that matters – the question of authenticity never crosses their minds. The theatrical set dressing used by these bars creates a fun environment. Even for those who recognize the dubious credibility of these establishments, some feel to have a “pub in a box” Irish bar is better than having none at all.

As America has helped transform St. Patrick’s Day into an all-out extravaganza, Irish pubs (authentic or otherwise) are increasingly patronized not only by the diaspora but by people of all backgrounds. The pub offers people of all stripes an environment that is hard to find anywhere else. The long tradition of the pub serving as a gathering place for the local community can still be carried out by these “pub in a box” bars … just don’t scrutinize the bric-à-brac too closely.

Added info: If you’re interested in standardized / templated restaurant experiences, you may also be interested in learning about how the Thai government’s culinary diplomacy has successfully spread Thai restaurants around the world.

The Rod of Asclepius vs the Caduceus

Often confused, the one without wings is the medical symbol.

the Rod of Asclepius

The Greek god Asclepius was the son of Apollo and became the god of healing/medicine. There are a host of legends about his medical powers – from his ability to heal the sick to his learning how to resurrect the dead. The most recognizable element of the Asclepius story though is his serpent-entwined staff.

The Rod of Asclepius is a wooden staff with a single snake coiled around it. Like Asclepius himself, there isn’t one consistent story explaining the snake. In one version a snake taught Asclepius the secrets of medicine, in another he watched one snake use herbs to revive another snake, etc. Over time the Greek association of medicine with snakes became intertwined (not unlike the Rod of Asclepius). Temples to Asclepius served as centers of healing, and given his association with snakes, non-venomous snakes were welcome. Snakes would crawl over patients’ beds and had free-reign of the buildings – Indiana Jones’ worst nightmare.

Over the millennia the Rod of Asclepius became an international symbol of healing & medicine. You can find it in the logo of the World Health Organization, a whole host of national medical associations, and on the side of ambulances everywhere … unless someone has accidentally used the caduceus instead.

The Caduceus

From the son of Apollo to the brother of Apollo, Hermes was the Greek messenger god who moved between worlds. After generously giving Apollo his tortoise shell lyre, Apollo returned the favor by gifting Hermes his wand / staff. This wand is known as the caduceus which has two snakes entwined around the wand with a set of wings at the top.

The image of a double snake wand is not unique to the Greeks. The caduceus has origins in ancient Mesopotamia going back to at least 3,000 BCE. Hermes isn’t even the only Greek messenger god to carry one – the goddess Iris also carries a caduceus. Like the Rod of Asclepius, there isn’t just one Greek explanation for the origin or meaning of the wand. One story says that Hermes saw two snakes fighting and he used his wand to break up the fight (and they became entwined around the wand). From this the caduceus has come to represent peace but it also represents trade as Hermes was the god of (among other things) commerce, cunning, and thieves. One thing it does not represent is medicine.

The Confusion

One reason for the confusion between these two symbols is they (more or less) look similar. Further, there is nothing about the Rod of Asclepius that looks particularly medical so it’s easy to forget which is which.

One of the biggest sources of confusion in the United States is the Army Medical Department (AMEDD). For some branch insignias the AMEDD uses the Rod of Asclepius but for others it uses the Caduceus (despite the caduceus having nothing to do with medicine). The Army mistakenly used the caduceus in 1851 and the mistake spread to other branches. At this point they are well aware they’re using the wrong symbol but won’t change.

Today it’s not uncommon to find the caduceus mistakenly on the labels of products that want to look more authoritatively medical, purely as a marketing tactic. Maybe using the symbol for commerce as a manipulative way to generate sales isn’t entirely a mistake.

Added info: perhaps at some point in the future the confusion will be sorted out but, if Starfleet Medical is any indication, the problem will persist until at least the 22nd century.

the Shamrock Shake & Uncle O’Grimacey

The McDonalds Shamrock Shake helped pay for the first Ronald McDonald house.

In 1970 McDonalds introduced their lemon/lime flavored green Saint Patrick’s Day Shake. It eventually changed flavors and names to become the mint flavored, and alliteratively titled, Shamrock Shake. Like the autumnal artificial scarcity of pumpkin spice, the Shamrock Shake is only available around Saint Patrick’s Day in the February through March timeframe (except in Philadelphia where it has two seasons).

McDonald’s founder Ray Kroc, Mayor Frank Rizzo, members of the Eagles organization, Fred Hill & his daughter all attended the opening of the first Ronald McDonald House, October 15, 1974.

Philadelphia’s two seasons of Shamrock Shakes goes back to the role it played in creating the first ever Ronald McDonald House. In 1969 Kim Hill, daughter of Philadelphia Eagle Fred Hill, was diagnosed with leukemia. By 1973 the Hills and members of the Eagles organization started the Eagles Fly for Leukemia charity which helped pay for the new oncology wing at the Children’s Hospital of Philadelphia (CHOP).

After seeing parents camped out in the hallways and waiting rooms while their children received treatments, the charity went a step further in 1974 and purchased an old seven-bedroom house at 4032 Spruce Street not far from the hospital. The house would be a place for visiting families to stay free of charge while their children received treatment – a “home away from home”. To help pay for this the Eagles partnered with the local McDonalds restaurants asking them to donate money from their next promotional food item, which just happened to be the Shamrock Shake. The Eagles asked them to donate 25 cents per shake but McDonalds executives asked if they could have the naming rights to the house if they donated all of the proceeds. Eagles general manager Jimmy Murray said “… for that money, they could name it the Hamburglar House.” From this, the first ever Ronald McDonald House was established in Philadelphia in 1974. Today there are more than 375 Ronald McDonald House programs around the world which, at what would have been more than 2.5 million overnight stays in hotels, save families around $930 million each year.

Uncle O’Grimacey

As positive as the Shamrock Shake’s impact has been, there have been some missteps. To help promote the Shamrock Shake, McDonalds introduced the new mascot character Uncle O’Grimacey in 1975. The Irish uncle of the purple mascot Grimace, Uncle O’Grimacey (complete in his kelly green hat, shamrock-patterned vest, and shillelagh) would travel from Ireland each year bringing Shamrock Shakes to McDonaldland. Uncle O’Grimacey was quietly phased out of McDonalds marketing after a few years due in part to an alleged incident in Philadelphia in 1978 where the person portraying him made statements in support of the IRA and that British soldiers were better dead than alive.

Casual racism isn’t just relegated to the semi-distant past however. In 2017 McDonalds ran an ad promoting the Shamrock Shake. Unfortunately they had a man wearing a tartan Tam o’ shanter playing the shake like a set of bagpipes (which would be Scottish) while standing in-front of Stonehenge (which is in England). McDonalds stopped the ad and apologized saying they are “… strongly supportive of Ireland and respectful of its culture”. Begosh and Begorrah.

Uncle O’Grimacey bringing Shamrock Shakes to McDonaldland.

Pareidolia and Who Is In The Moon

A man’s face, a rabbit – different cultures see different things because humans are hardwired to look for patterns.

Over thousands of years of evolution our brains are hardwired to find patterns. For example, finding the pattern of tiger stripes in the tall grass is a pretty valuable skill to have. We use pattern recognition for defense, for finding information, for reading faces, etc. As our brains are constantly searching for patterns we’re bound to get it wrong sometimes and find meaning in things where there is none.

Pareidolia is when we incorrectly recognize something where there is really nothing. This can be auditory, such as “hearing” a word in what’s really just random sounds or white noise, but most of the time pareidolia is visual. We “see” animals in clouds, we “see” butterflies in Rorschach inkblot tests, etc. Facial pareidolia is when we see faces in things such as electrical outlets, the front of cars, burnt grilled cheese sandwiches, or even on the surface of the moon.

Who is on the Moon?

The surface of the moon is marked by impact craters from asteroids as well as large craters of solidified ancient lava. In the same way ancient humans connected the stars to create constellations, people have looked at these lunar markings and “seen” a variety of things.

The Man in the Moon

A European tradition going back to at least the 14th century finds the whole body of a man carrying sticks on the surface of the moon. While stories vary, he’s said to be a man caught gathering sticks on a Sunday. As punishment for breaking the Sabbath he was banished to the moon.

The Haida of the Pacific Northwest North America see this shape as a boy (instead of a man) who had been gathering firewood by moonlight. The boy insulted the moon and was similarly banished to the moon as punishment.

Other traditions see just the face of a man and not the whole body. Some say the man is Caine from the Bible, also sent to the moon as punishment. Talmudic folk tradition says this person is Jacob.


Jack & Jill

The nursery rhyme of Jack & Jill is based on the Scandinavian myth of Hjuki and Bila. The two children were said to be carrying a pail of water when the moon god Mani carried them to the moon (where they can be seen carrying their pail).


The Woman in the Moon

Sometimes the man/boy carrying sticks on the moon is said to be a woman (a witch of course) carrying sticks. In the southern hemisphere however, where the moon is seen upside down (depending on your cultural point of view), the Māori of New Zealand see a different shape as a woman. Rona was carrying water at night but tripped when there was insufficient moonlight to light her way. Hurt and angry she cursed the moon. The moon heard her insults and (like the punishment in the Haida legend) she’s now on the surface of the moon along with her water jug.

The Samoans say this woman is Sina, who thought the moon looked like a giant breadfruit and asked the moon to come down to let her child have a bite. The moon, insulted by this, took Sina, the tools she was working with, and her child back to the moon.


A Pair of Hands

In some Hindu traditions the hands of Astangi Mata are seen on the surface on the moon.


Name of Ali

In Islam, where there is a history of aniconism and not depicting sentient beings in art, there is a Shiʿite tradition of seeing the name of Ali (the son-in-law of Muhammad) written on the surface of the moon.


A Rabbit

In India the Buddhist Jātaka tales have a story of a rabbit that sacrifices itself by jumping into a fire. The rabbit is saved and placed on the surface of the moon. In China the rabbit Yutu is seen on the moon preparing the elixir of life in a bowl. The Japanese also see a rabbit with a bowl but instead of a magical elixir it’s preparing rice cakes.

Mesoamerican groups also see a rabbit on the moon. As the one story goes Techuciztecatl (the moon) was hit in the face with a rabbit, the imprint of which is still on the moon.


A Toad

The Selish people tell of a wolf who was romantically pursuing a toad in the moonlight. Just before being caught by the wolf the toad leaped so high she landed on the moon. Another toad on the moon is a variation of the Chinese rabbit on the moon story. In this version after the rabbit prepared the magical elixir for the Moon goddess Chang’e, the goddess drank the elixir and was transformed into a toad.

The Kimbundu tribe of Angola have the story of a prince who was only permitted to marry the daughter of the moon. Only a frog knew the way to get to the moon so he served as messenger between the Earth and the moon. Now the frog can be seen on the moon.


Thousands of years of humans have looked up at the moon from cultures around the world and have, through creativity and pareidolia, seen a variety of things. Cultures have explained these figures with creation myths or moral lessons, giving us the stories we know today.

Bonus: One of the most famous versions of the man in the moon is seen in the 1902 Georges Méliès film Le Voyage dans la Lune.

The Georges Méliès film Le Voyage dans la Lune (A Trip to the Moon) is a classic early film.

Acquired Overbites

We have slight overbites because we use forks & knifes.

Before people ate with knives & forks they used their hands. In the absence of utensils people would have to clench and rip their food with their teeth. While crude, the result of all this pulling meant that people’s top and bottom rows of teeth lined up edge-to-edge. The introduction of utensils changed that.

The use of a knife & fork meant that a person no longer had to use their teeth to pull at their food, they could cut their food on their plate first. As a result anyone who used utensils (including us today) developed an overbite. Most of us have slight overbites where our top teeth hang out a bit in front of our bottom teeth, which comes from using utensils.

Looking at skulls we can see this effect across time, across cultures, and across social classes. Aristocrats could usually afford knives & forks before the peasantry, so they developed overbites before anyone else. For example, the more affluent members of 18th century Western Europe developed overbites before the people who couldn’t afford silverware. Further, the overbite took longer to develop in the American colonies, who were poorer than their countrymen back home in Europe.

In China the overbite developed as far back as 800 CE. Instead of knives & forks the Chinese aristocracy used chopsticks, but to eat meat with chopsticks the meat had to be pre-chopped as part of the meal preparation. As a result they didn’t have to pull at their food either and developed overbites centuries before Europeans.

QI discusses the development of overbites, and as it pertains to Richard III

Experiences Over Things

We get more happiness from the experiences we have than the stuff we buy.

Americans buy (and store) a lot of stuff, so much stuff that self-storage facilities have become a booming industry over the last decade. In 2021 an estimated 10.6% of American households (13.5 million households) rented space in self-storage facilities. These are people who have so much stuff they can’t fit it all into where they live and, instead of getting rid of some of it, have chosen to rent more space.

Physical objects last longer than fleeting experiences and so it would seem logical that the happiness derived from these objects should be equally as long lasting. Unfortunately this is not the case. Multiple studies have shown that experiences make us happier than objects do. The novelty of objects and the happiness we get from them tends to wear off fairly quickly once we become accustomed to them. Even worse, the longer objects are with us the more likely they’ll break or in some way become a frustration. Your fast new computer eventually becomes a slow & buggy headache. Further, when it comes to gift-giving, most people give physical objects that they feel will make the recipient happy, but these gifts really just contribute to the cycle of more stuff and less happiness. Experiences are different.

“Let us rather run the risk of wearing out than rusting out.” – Theodore Roosevelt

Experiences (not things) make us who we are

The happiness associated with an experience (a vacation, a concert, going to an art exhibit, learning a new skill, etc.) can actually increase over time. Even a negative experience can eventually become more positive after enough time passes – an idea known as “Type II fun.” A rainy vacation isn’t as fun as it could have been, but after a while you can appreciate the bonding time you had indoors with your family or friends. At the very least it can make for a good story, which, talking about a bad experience has also been shown to improve your assessment of an experience.

Our experiences become a part of who we are. We bond with other people over shared experiences – we don’t bond over owning the same smartphone. Further, we are less likely to negatively compare our experiences with those of others. It’s fun to talk about traveling and share recommendations with one another. This is different than comparing possessions which (in a “keeping up with the Joneses” kind of way) tends to be negative. Is your car as nice as your coworker’s, is your house bigger than your neighbor’s, what is the number of carats in her diamond ring, etc. Unlike comparing experiences, comparing stuff doesn’t make us any happier.

As the 2014 study Waiting for Merlot: Anticipatory Consumption of Experiential and Material Purchases put it, “Experiential purchases (money spent on doing) tend to provide more enduring happiness than material purchases (money spent on having).”

Agent Cooper of Twin Peaks shares his life advice to, “Everyday, once a day, give yourself a present.”

Indigo & Isaac Newton

Indigo was included in the color spectrum by Isaac Newton because he wanted the spectrum to have seven colors instead of six.

Isaac Newton’s pioneering experiments with light & prisms explained how white light is actually the combination of several wavelengths (colors) of light. He demonstrated this using a prism to break apart white light into its composite colors and then used a second prism to recombine those colors back into white light. When white light is broken apart the “spectrum” (a word Newton introduced to the field of optics meaning a “continuum of color”) has many colors. Exactly how many colors is open to cultural interpretation.

Isaac Newton refracting white light through a prism, demonstrating that white light is comprised of more than one wavelength of color.

Any Color You Like

Most human eyes are essentially the same which means that most of us are physically capable of seeing & differentiating all of the same colors. Where we differ is how we think about color. Your culture & language influences how you categorize colors.

The importance of, and names for, different colors varies from culture to culture. For example, the medieval English didn’t have a name for the color orange until the 16th century, so before then things that were orange were just called red (like “redheads” and the robin “redbreast”). It’s not that they couldn’t see orange, they just didn’t have a name for it because having two distinct names for red and orange wasn’t important until then. Russian, Greek, Turkish, and Hebrew all have two different words for idea of blue: one for darker blue and the other for lighter blue.

Hungarian has two different words for red depending on what you’re describing. “Piros” is used for red inanimate objects or red cheerful things, while “vörös” is used for red animate things or red serious things. Irish Gaelic has two words for the idea of green depending on where it’s seen. “Glas” is used for the green of plants while “uaithne” is used for the green of artificial dyes. The hue of a plant and a sweater could be exactly the same, but in Irish Gaelic different words will be used for the idea of green. In a nutshell: the names, categorization, and importance of various colors is entirely influenced by which culture we are a part of.

This cultural influence also applies to the spectrum of color and rainbows. Illustrations of rainbows contain discreet, countable, bands of colors. In nature however they’re continuous gradations of wavelengths/colors. Assigning a fixed number of colors to a rainbow depends on your cultural interpretation. In Islam, rainbows traditionally only have 4 colors corresponding to the four elements of water, earth, fire and air. Western culture should probably only have six colors, but we have seven because of Isaac Newton’s interest in mysticism.

Isaac Newton included seven colors in his spectrum because he felt the number seven was mystical & important. To do this he selected one tertiary color, indigo, to be included in his list of colors.

The Sacred Seven

As scientifically minded as Newton was, he also held occult/mystical beliefs. He believed in sacred geometry and the ideas of Pythagoras that there was an importance to the number seven. At first, after refracting white light, Newton recorded observing five colors (red, yellow, green, blue, violet). Then he recorded seeing six (he added orange). But to Newton six wasn’t as satisfying as seven. There are seven notes in the western major scale, seven days in a week, seven known “planets” in the sky (in Newton’s time), but only six colors in the spectrum of light? This wouldn’t do, so he added indigo.

The first six colors he observed are a logical western division of the spectrum:
• three primary colors (red, yellow, blue)
• three secondary colors (orange, green, violet)

Indigo is a blend of blue + violet and as such is the only tertiary color he included. It’s not that indigo isn’t part of the spectrum (it’s definitely there), but rather the problem is that it’s the only tertiary color listed because Newton shoehorned it in. Why indigo? Why not vermillion or cerulean? Indigo’s inclusion was an arbitrary choice driven by Newton’s desire to have seven colors instead of six so he picked one tertiary color but ignored the five others. Cultural influences pushed him to find seven colors instead of six (or eight, or twelve, or any other number). Centuries later we still divide the spectrum into seven colors because of Newton.