The shortest distance between two points is a straight line, right? Not necessarily! That depends on the scale of what we are talking about. True, the most direct path from one side of a room to the opposite side is a straight line. We can measure the span to prove this.
However, when we use a much larger scope—a global scale, perhaps—a straight line as measured on a map is not necessarily the fastest way to move between two points. How can that be?
Most maps are printed on flat pieces of paper. The most commonly used is called the Mercator projection, which projects the spherical world onto a flat, two-dimensional surface, exaggerating the size of the northern and southern polar areas.
Pull up a map. As you can clearly see, the island of Greenland—located up by the North Pole—is depicted as a huge landmass. As a matter of fact, it is merely two-thirds the size of India, which appears smaller as it lies much closer to the equator. This distortion of space on flat maps warps our impression of straight lines and of relative distances.
As an example, suppose you want to journey from New York to Taipei. Using a typical Mercator projection map, you would assume that the best flight route would be by heading west via the continental US and over the Pacific Ocean.
In reality, that itinerary would be a considerable waste of both time and money. To show why, prepare a piece of string and get hold of a globe. With one end affixed to New York and the other to Taipei, pull the strandtaut. Surprise! Now, you’ll have to concede that the shortest distance is going north over Alaska and Russia, then southward towards Taipei.
