What is Science?

It is a sad fact that many of our daily assumptions, and even some goverment policies, are based on misunderstandings of what science is and what it can be used for. Before we discuss any scientific findings, it is vital to understand what science is - and what it is not. When I use the term "science," I refer to the process whereby we try to understand the universe around us, and, based on what we observe, make predictions about how the universe operates. Essentially, science is a matter of constructing models of natural processes, and refining and replacing them to fit new data.

Sound confusing? Well, let's try to boil it down a bit. When we talk about a model airplane, we mean a representation of a real airplane which shares some, but not all, characteristics of a real plane. It looks like a plane - in miniature - but will have important differences from a real plane (as few airplanes are constructed of plywood these days). When we talk about a scientific model, we mean a set of statements (usually in mathematical language) that represent some aspect of the real universe, although they will only be an approximation of the real processes. Like a model airplane, however, the scientific model gives us an idea of what the real thing looks (or acts) like.

For instance, let's take the ever-popular Newtonian Law of Gravity. In the English language, this states that objects which have mass attract one another, and the greater the masses, the greater the attraction; while the greater the distance between them, the less the attraction. In mathematical language we state this as F = GMm/R². So, looking at this model, we say: if I drop this apple, the Earth will pull on it a lot, while the apple pulls on the Earth a very, very little; thus the apple will fall toward the Earth at a certain acceleration. And, when we measure the speed of the apple's fall over time, we find that it has an acceleration very close to what our model said. Now, remember that real airplanes aren't made of plywood, and the real universe is more complicated than any model we invent to explain it. In actual fact, a dude named Albert Einstein found out that adding certain corrections to Newton's Law of Gravity made it more accurate. These corrections are very small, and only significant for certain situations - but that does become important when, for instance, you're trying to guide a spacecraft on a path between planets.

This brings up another question - what's a scientific theory, what's a scientific law, and what's the relationship of either to a model? Well, a scientific theory is exactly the same thing as a scientific model - it's a statement of the way the universe works in certain situations. A "law" is, frankly, a very bad term; it only means a scientific theory that's been around so long, and is so well supported by the evidence, that we tend to assume it is accurate in most situations. Einstein's correction to Newton's Law of Gravity demonstrates that no scientific law is so firm that it may not need adjustment - or replacement - as the evidence demands.

Scientific theories and models are based upon evidence. This point cannot be stressed enough. A theory is only accepted as valid and worthwhile as long as the evidence supports it; when the evidence contradicts the theory, it's always the theory that must give way. Models must be constantly checked against the available data, refined to match the data, and thrown out when they can no longer provide such a match. The whole process of science is often referred to as the Scientific Method, which goes something like this: