I have, in recent months, further fleshed out my thinkings on the nature of science. I have concluded that it doesn’t contain any truth or knowledge of the nature of the world, but is rather a convenient model used to make predictions. For example, the theory of gravitation says any two objects with mass will exert a force on each other, proportional to the product of their masses and inversely proportional to the square of the distance between them. Using this law we can make the prediction that if you let go of your tasty ham and cheese sandwich, it will fall to the floor as a result of experiencing a force from the earth. The theory is useful because of its nature to make valid predictions.
Scientists in the late 1800’s thought they had ‘figured out’ all of physics – meaning they had come up with a model that would predict any possible behavior of a physical system. They had a few loose ends to wrap up, sure, but they had gotten most of the hard work done. Then, a problem arose – there were physical phenonemena that could not be predicted by their model, phenomena like the emission spectrum of hydrogen gas. So they did what any scientist does – attempted to modify their model in order to get it to predict this new behavior. As more and more new unpredictable phenomena were discovered, The previous model that was being used fell part because it couldn’t be adapted to account for these new phenomena. It was first decided that mabye light energy wasn’t always continuous, but exchanged in discrete amounts – and then maybe it could only exist in discrete accounts. Atoms went from being little pudding cups to tiny solar systems to oscillating soap bubbles. They didn’t change because scientists suddenly had a better understanding of the atoms; they changed because you couldn’t use the old model of atoms to predict everything they were observing.
In summary, then, science is the proces of creating a mental model of the world, in order to make accurate predictions about the world. It’s important to note that there isn’t anything in science that exists out of anyone’s mind. For example, suppose you operate under the assumption that there is a goblin living inside your car, and he sustains himself by drinking a bit of your motor oil now and then. If there’s no oil for him to drink, or if the oil is all dirty, he’ll get mad and start banging things around in your engine, causing damage to your car. This goblin idea could be considered the ‘goblin theory’ if you wish, and it should be noted that you can use the goblin theory to predict two things:
- Because the goblin occasionally drinks a bit of your oil, it will run out if you don’t refill it now and then
- If the oil in your car runs out, or you don’t change it frequently enough, your engine will be damaged.
Both of those predictions are useful predictions, but they came from a theory we would consider totally bogus. You could explain the entire workings of your automobile with a managerie of goblins if you wished, and so long as you described those goblins properly your theory could always be used to predict the observed behavior of your car, even though there aren’t really any goblins. Note, then, that the ability of a theory to make meaningful predictions does not imply that there’s anything ‘true’ about that theory.
Now, here’s the peice de resistance: The idea of an external world, a world outside our own minds, is itself a scientific theory. When we come into the world, we’re bombarded with any number of sensory perceptions, and our mind has a mad scramble to make sense of what exactly these sensory perceptions mean. The easiest way to make predictions about the nature of those observations is to assume the existence of a physical, euclidean world, inhabited by objects with various properties. When you see a hot stove and decide not to touch it, what’s going on is you’ve got a mental model of this stove thing, and your model predicts that if your fire your nerves in such and such a way, eventually there’ll be a rather rapid signal along a different set of nerves, and this signal will trigger the release of certain chemicals, which is to be avoided. So you don’t touch the stove.
Note that the model most people have the the world around them is entirely inconsistent with modern scientific theories. Most people think of physical objects as being solid; taking up space and all that sort of thing. According to modern atomic and moleculary theories, everything around you is a fine mist of tiny particles, held in place by electric fields. When you’re listening to linkin park and you’re so mad at your parents that you punch the wall, your fist never comes in contact with the wall. An electric field due to the presence of the electrons on the outside the wall exerts a force on your fist, causing it to come to a stop before any ‘contact’ is made. Most people don’t bother to think about that because it’s really not necessary – you can approximate the wall as being solid and you’ll be able to predict behavoir very accurately, so there’s no point in disregarding that model.
Consider another take on the same idea – you learn in biology about how people are made up of cells and the cells do this that and the other thing. If you were going to buy someone a present, you wouldn’t predict their response by trying to predict the internal binary configuration of their brain and the nature of the signals sent to it by the reciept of their gift, even though according to ’science’ that’s what’s really going on. The reason is because it’s damn near impossible to use that model to make any sort of reasonable prediction, so you instead resort to a different mental model of how people interact.
My whole point is that, in order to predict the nature of the observations we’ll make in the future, we create mental models. The study of Physics is the study of a model that can be used to accurately predict any number of phenomena. Chemistry is the same way. Biology is, too albeit to a lesser extent. The models we create aren’t limited to scientific pursuits, however – the very idea of a world outside of our own minds is simply the model that is best at predicting the nature of sensations we will experience in the future. Draw your own conclusion.