By the end of the 20th century, the race to build the world's tallest skyscraper ground to a halt. Each new contender was only slightly taller than the one before, and architects were running out of ways to top their previous efforts.  But in 2004 construction began on a new building in Dubai, promising a revolutionary design that would dwarf the competition. In 2009, the 828-meter Burj Khalifa was complete, surpassing the previous record-holder by over 60%.  So what innovations allowed for such a huge leap in height? For most of architectural history, heavy building materials mad ..read more

Socrates, one of the founding fathers of Western philosophical thought, was on trial. Many Athenians believed he was a dangerous enemy of the state, accusing the philosopher of corrupting the youth and refusing to recognize their gods. However, Socrates wasn’t feared for claiming to have all the answers, but rather, for asking too many questions.  While he loathed formal lectures, the philosopher frequently engaged friends and strangers in lengthy conversations about morality and society. These discussions weren’t debates, nor would Socrates offer explicit advice. In fact, the philosop ..read more

  Chapter 1 Chapter 2 If you encounter any problems, Write to us in Contact Us section. We will try to fix the problem ..read more

Your favorite cricket closes in for a victorious win. The crowd holds its breath, and, at the crucial moment, he misses the shot. That competitor just experienced the phenomenon known as "choking," where despite months, even years, of practice, a person fails right when it matters most.  Choking is common in sports, where performance often occurs under intense pressure and depends on key moments. And yet, performance anxiety also haunts public speakers, contestants in spelling bees, and even world-famous musicians.  Most people intuitively blame it on their nerves, but why does be ..read more

The year was 1776. In Bavaria, new ideals of rationalism, religious freedom, and universal human rights competed with the Catholic church’s heavy influence over public affairs.  Across the Atlantic, a new nation staked its claim for independence on the basis of these ideas. But back in Bavaria, law professor Adam Weishaupt’s attempts to teach secular philosophy continued to be frustrated. Weishaupt decided to spread his ideas through a secret society that would shine a light on the shortcomings of the Church’s ideology. He called his secret society the Illuminati.  Weishaupt model ..read more

Did you know that the human eye can differentiate 10 million different colors? But what color is a mirror? You might say "silver," because mirrors are often illustrated that way, and, to be sure, they are made out of silver or silvery things like aluminium.  But a mirror, in reality, is whatever color you point it at. In a green room, the mirror is green. And if you look inside a mirror, it becomes "you-colored." An object is whatever color it doesn't absorb. In below picture, sticky notes are orange because when hit with typical white light, they absorb every other wavelength of visib ..read more

In the late 17th century, a medical student named Johannes Hofer noticed a strange illness affecting Swiss mercenaries serving abroad. Its symptoms, including fatigue, insomnia, irregular heartbeat, indigestion, and fever were so strong, the soldiers often had to be discharged.  As Hofer discovered, the cause was not some physical disturbance, but an intense yearning for their mountain homeland. He dubbed the condition nostalgia, from the Greek "nostos" for homecomingand "algos" for pain or longing.  At first, nostalgia was considered a particularly Swiss affliction. Some doctors ..read more

On July 26, 1943, Los Angeles was blanketed by a thick gas that stung people's eyes and blocked out the Sun. Panicked residents believed their city had been attacked using chemical warfare. But the cloud wasn't an act of war. It was smog.  A portmanteau of smoke and fog, the word "smog" was coined at the beginning of the 20th century to describe the thick gray haze that covered cities such as London, Glasgow, and Edinburgh.  This industrial smog was known to form when smoke from coal-burning home stoves and factories combined with moisture in the air. But the smog behind the LA pa ..read more

Cigarettes aren’t good for us. That’s hardly news -- we’ve known about the dangers of smoking for decades. But how exactly do cigarettes harm us?  Let’s look at what happens as their ingredients make their way through our bodies, and how we benefit physically when we finally give up smoking.  With each inhalation, smoke brings its more than 5,000 chemical substances into contact with the body’s tissues.  From the start, tar, a black, resinous material, begins to coat the teeth and gums, damaging tooth enamel, and eventually causing decay.  Over time, smoke also damages n ..read more

Sitting around a campfire, you can feel its heat, smell the woody smoke, and hear it crackle. If you get too close, it burns your eyes and stings your nostrils.  You could stare at the bright flames forever as they twist and flicker in endless incarnations. But what exactly are you looking at?  The flames are obviously not solid, nor are they liquid. Mingling with the air, they’re more like a gas, but more visible--and more fleeting.  And on a scientific level, fire differs from gas because gases can exist in the same state indefinitely while fires always burn out eventually ..read more