Thursday, November 29, 2007

3 Great Scientific Discoveries
Technological breakthroughs get big press because they can give us new tools and toys. We feel technology's impact directly: wheels and gears, zippers and microchips--the list is endless. But where would technology be without scientific discovery?Nowhere, I say. Technology marches on a highway laid down by those absent-minded geeks who merely figure out what's true. So what are the ten greatest scientific discoveries of all time? Here's my list:1. The Pythagorean Theorem. It's a staple of high school geometry: in every right triangle, a2 + b2 = c2 , where a and b stand for the two short sides and c for the long. The first to prove this was (probably) the Greek philosopher Pythagoras in the 6th century bc. But it's not the theorem per se that matters; it's the bigger idea it reflected. Pythagoras taught that numbers were the real reality, that the core of the physical world was mathematical. That's why he went around telling everyone, 'Here's a pure idea that is true of every actual object of a certain shape.' Coupling physics to mathematics proved to be one of the most fruitful marriages of all time. Even now we regard a scientific theory as really reliable if it can be proven mathematically.

2.The existence of microorganisms. In the late 1600s, when microscopes were new, Dutch lens maker Antoni van Leeuwenhoek scraped some plaque off his own teeth and looked at it through a microscope. Gasp! It was crawling with "animalcules." In fact, tiny creatures invisible to the naked eye abounded everywhere, he found. Less than two centuries later, knowledge of this invisible universe enabled Louis Pasteur to construct his "germ theory of disease,"which in turn enabled doctors to conquer a whole host of diseases: typhoid, typhus, polio, diphtheria, tetanus, smallpox tuberculosis, anthrax--the list goes on. The leading cause of death changed after that from infectious disease to heart disease, cancer, and "old age." See Bacteria.

3.The three laws of motion. Pythagoras would have been so proud of Isaac Newton! More than any scientist in history, this 18th-century Englishman succeeded in reducing physics to mathematics. Newton came up with three laws to explain the motion of all objects in the universe, from runaway trains to orbiting planets. (He also invented differential calculus, explained gravity, and discovered the spectrum*--not bad for one lifetime.)