What is a scientist? That’s a question easier to ask than it is to answer.The first person we know of who might be called a scientist was Thales of Miletus, who lived in Ionia, now the west coast of Turkey, around 600 B.C. Aristotle said he founded “natural philosophy” — the notion that even huge occurrences like earthquakes have simple causes similar to those we observe all the time on a smaller scale. His theorized that the Earth floats on water, and that earthquakes are obviously the result of the Earth rocking on the celestial sea, thus becoming, not only the first scientist, but also the first scientist to get things completely wrong.A series of later Ionian philosophers had more lasting impact. They thought that the way to discover the basic elements of the universe would be to figure out what remained the same through all nature’s changes: when water freezes or evaporates, when a log burns to smoke and ash, or when a plant grows, blooms, dies and decays.
Leucippus, a century or so after Thales’s death, came up with the idea of atoms (meaning “uncut”), the smallest pieces of matter, which, roaming though empty space, hook up in various ways to form everything — pretty much how we see it today, more than 2,000 years later.
These early Greeks still weren’t really “scientists” in the modern sense of the world, though, because they had little use for observation or experimentation, preferring to ignore observations that didn’t fit in with their ideas.
Modern Western science really took shape in the 16th and 17th centuries in Europe, with Sir Isaac Newton as one of the principal sculptors: his book Principia, published in 1687, provided a unified description of all types of motion and united two threads of science the Greeks had but never wove together: systematic observation and mathematics. Besides being a model work for succeeding generations of science, Principia convinced the general public that science had to be taken seriously, because in it Newton displayed an astonishing ability to make accurate predictions.
Today we talk about the scientific method: observation leads to a theory, a generalization about the way things are. The theory gives rise to a hypothesis, a prediction that can be tested through experimentation or further observation. The results of that test may lead to a modification or extension of the theory, which generates another hypothesis, which leads to more experimentation, and so on. This ongoing process (although seldom this cut-and-dried) gradually gives rise to reasonably certain inferences about the nature of the world.
Mathematics plays an important role, because, as Newton showed, if a theory can be stated mathematically, it can be used to make precise predictions of future events.
The power of the scientific method is apparent when you look at what’s happened since Newton. Science has created a world that the ancient Ionians would find magical (and probably terrifying). Unfortunately, too many present-day people see it the same way: disturbing, because, if we’re to deal with the accelerating pace of technological change, we must learn not to fear science, and particularly not to view it as something that only involves white-coated geniuses or calculator-packing nerds. In reality, scientific thinking is something everyone can and does apply.
For example: You observe that the car in front of you skidded around the corner you’re approaching. You theorize that the road is slick. If that is true, you hypothesize, then if you lightly touch the brakes you’ll feel a little skid. You experiment by lightly touching your brakes — sure enough, you skid. From this you infer that, yes, the road is slick. A further hypothesis would be that if you round the corner too quickly you’ll skid into the ditch, but it is possible to carry experimentation a little too far.
Congratulations! You’re a scientist. A scientist is just a human being who uses his brain to figure out how things work.
Maybe those ancient Ionians wouldn’t feel so out of place here after all.