Posted in History & Literature

Evolution Of Colour

We often take the beauty of colour for granted. How would you explain the colour red to a blind person? With that in mind, how do we know that the colour we see with our own eyes is the same hue that others see? A scholar by the name of William Gladstone came across a similar question in 1858 while studying ancient Greek literature. He noticed that in most literature of ancient times, the description of colour was wildly inconsistent, such as the sea being described as “wine-dark”, the sky being “copper-coloured” and other oddities such as violet sheep and green honey. After further analysis, Gladstone found that white and black were referenced frequently, while other colours were much rarer, with red, yellow and green being the most common colours respectively.

Another scholar named Lazarus Geiger expanded on Gladstone’s research and found that throughout ancient literature – including the Bible, Hindu poems, ancient Chinese stories and Norse tales – described beautiful scenes while omitting a certain detail: a blue sky. It appeared that the colour “blue” did not appear in most languages until a certain point in time, despite the people having lived under the same blue sky that we do now.

Geiger tracked the appearance of different colours in different languages and found a pattern of development. Each language would typically describe white (light) and black (dark) first. The next colour to develop was red, then yellow and green, with blue being one of the last colours to appear. This is likely related to the abundance of each colour (e.g. blood, dirt, vegetation) and the ease of making coloured dye (blue dye is notoriously difficult to make).

This raises an interesting question: if the ancient Greeks did not have a word for the colour blue, could they still perceive the colour blue? Biologically speaking, our eyes are not so different to that of the ancient Greeks. But of course vision is a two-part processyour eye captures the image and then your brain processes the image. Does language have a significant enough impact on how we perceive our world?


There is a tribe in Namibia whose language does not distinguish blue and green. A study was held where people from this tribe were shown a circle of 12 squares – 11 green and 1 blue. To the researcher’s intrigue, the men and women of the Himba tribe could not tell which square was the odd one out – suggesting that their brain was processing the two colours as identical. However, the Himba language has more words distinguishing shades of green than English. In another study involving a circle of green squares with one square being a slightly different shade of green, the Himba tribe could pick out the different square much more easily than English-speakers.

The so-called “colour debate” is a hotly debated topic, with some arguing that language plays a crucial role in determining our perception of the world, while others state that language is separate to our senses. What did the ancient Greeks see when they gazed up into the sky? If we cannot describe something with words, then does it truly exist? But one thing is clear – things are not always as they seem.

Posted in Psychology & Medicine


Scrubs is the uniform that surgeons, anaesthetists, emergency department doctors and nurses wear for the freedom and mobility required in activities such as surgery and CPR. Also, since it is owned and washed by the hospital instead of being privately owned, it is more hygienic and helps prevents infections. A noticeable trait of scrubs (and also surgical gowns) is that almost every hospital uses a shade of blue or green instead of white. Why is this?

The reason being, looking at a surgical scene for a long period of time can cause eye fatigue and afterimages due to the redness of blood and organs. Afterimage is a phenomenon that occurs when the retina becomes insensitive to a strong colour and instead making the complementary colour stand out more. Ergo, a surgeon looking at blood and organs for too long will see afterimages of a blue shade, which may cause accidents to happen as it overlaps on white surfaces or the surgical field. Clothing of blue or green colour neutralises the afterimage and is much easier on the eyes, reducing the fatigue. Lastly, blue-green colours have a calming psychological effect, which helps in a high-tension, stressful environment such as in an operating theatre.

Posted in Psychology & Medicine


Spinach is a vegetable that is excellent for your health as it is rich in nutrients such as vitamins and minerals. If you ask someone the first two things that come to mind regarding spinach, they will most likely reply Popeye and iron. Popeye is a cartoon that began airing in the 1930’s and every child knows that the man gains superhuman powers from eating a can of spinach. In fact, after Popeye began airing, US consumption of spinach grew 33%. Most people believe that Popeye gains powers due to spinach having a high iron content. Thus, adults always tell children that if they want to be as strong as Popeye, they must eat their spinach.

Unfortunately, eating spinach does not make you as strong as Popeye. In fact, it is not even related to iron either. Firstly, the reason why Popeye eats spinach was because the producers wanted to advertise the high vitamin A content in spinach. Furthermore, spinach does not have a high iron content. The spinach iron myth originated from a German scientist named Emil von Wolff. In 1870, von Wolff was analysing the nutrition contents of different foods when he, from severe fatigue, accidentally misplaced a decimal point while recording the iron content of spinach. This led to spinach being known to have ten times the amount iron it actually has (to the level of red meat).

One problem with this is that this story is not true either. There are no detailed records of von Wolff’s experiments and no one knows if he misplaced a decimal point or not. The myth most likely originates from a 1980 article in The British Medical Journal that first brought up the story. Does that mean spinach is actually is a good source of iron? Wrong. Vegetarians often claim that spinach has iron levels close to red meat, but there is something about iron that they do not know. Many plants have a high iron content (it is found in chlorophyll which is used for photosynthesis), but this is mostly non-heme iron. There are two types of iron the human body can absorb: heme and non-heme. Heme iron can be used directly after absorption whereas non-heme iron needs to be metabolised by the liver to be usable. This takes a long time and is inefficient meaning it is far more effective to eat foods rich in heme iron. Plant iron is all non-heme iron while 40% of iron in red meat is heme iron, meaning it is a much better source of iron. Furthermore, spinach has a high oxalate content, which is an iron absorption inhibiting agent, making what little usable iron it has unabsorbable. 

In short, it is true that spinach has “iron” but as we cannot absorb it or use it, it practically has no iron content. But if you tell this to your parents and refuse to eat spinach, you may get into a lot of trouble.

Posted in Science & Nature

Complementary Colours

Red, green, blue, white… There are many colours that we can see and there are even more different combinations of colours possible. It is common knowledge that some colours clash with each other while some synergise very well. A common example of a “good combination” is when you use complementary colours. Complementary colours are two colours that oppose each other on the colour wheel, creating an effect where they brighten each other. This makes it very eye-catching and attracts people’s attention. For example, blue and orange make a bright contrast making them a popular colour choice for movie posters. Red and green, and yellow and purple are also examples of complementary colours. Complementary colours are an important concept in art and design as it helps the product stand out.

Complementary colours have an interesting relationship with our sense of sight. If you stare at a colour for a while then quickly look at a blank, white surface, you will see an afterimage of the complementary colour. A good example is when you have your eyes closed under bright sunshine and upon opening your eyes the world seems a blue hue (the blood vessels in your eyelid make the light appear orange as it reaches your eyes). This is because the retinas try to negate the intense colour by downregulating the nervous signals corresponding to that colour, which makes the complementary colour stand out. Furthermore, the photoreceptors in the retina become fatigued after stimulation, causing a reduction in the signals sent for that colour.

Knowing about complementary colours is very useful when designing a sign or poster that easily attracts people.

(Image source

Posted in Science & Nature

Urban Paradox

A few years ago, a theoretical physicist studied population growth in cities to find the mechanism of how cities operate. What he found was an astonishing law.
Wherever the city, as the population doubled in size, the average income, number of patents, number of educational and research facilities and other important numbers all increased around 15 percent. Although it is normal for such statistics to increase as a city grows, it is interesting to see that almost all of them increasing at a similar rate, despite being so different sometimes.
More fascinating is the fact that not only do the above “good” statistics increase equally, but so do crime rates, pollution, smog occurrence, stomach flu and AIDS prevalence all increase approximately 15 percent.
Therefore, a city can be seen as a double-edge sword that is both the source of fast growth, wealth and ideas, but also waste, pollution, stress and disease.

Biologically speaking, an organism has a tendency to have slower growth and pace of life as it gets larger. For instance, an elephant’s heart beats slower than a mouse, and its cells do less work on average too. However, a city exhibits a snowball effect where it grows faster as it gets larger. To achieve this extremely high rate of growth, it must consume an immense amount of resources, which ultimately ends up as large quantities of waste and pollution. Also, as people get busier, the overall “quality” of the society falls, leading to increased stress and disease prevalence.

If so, should we abandon our current productivity and live a slow, village life and ignore our potential as a species? Or should we continue our exponential growth at the cost of using up nature’s well-maintained resources like no tomorrow?

Posted in Science & Nature


There is a bamboo forest on a desert island. How can you use these?

  • If you cut a section of bamboo so that one side is open, one side is closed, it becomes a cup.
  • If you cut a section of bamboo and split it lengthwise, it becomes a dish.
  • If you cut a section of bamboo and cut a wide hole in the side, it becomes a pot.
  • If you cut a section of bamboo and fit a large rock on one end, it becomes a hammer.
  • If you cut a branch of bamboo and craft it, it can be a spoon, fork or chopsticks.
  • If you take a stick of bamboo and tie a string and hook at the end, it becomes a fishing rod.
  • If you take a stick of bamboo and sharpen the end, it becomes a spear.
  • If you take many large bamboo and tie them together, you can make a house, a bed or a raft to escape in.

The most important rule of survival is application.

As an addendum, bamboo is a grass (the largest in the world), not a tree.
This is because its stalk has become hardened yet still hollow, making it look like a tree. However, it has segments, shallow roots and dies after flowering (which can take decades) that are features of grass.