'Science' is a term that is much abused and misunderstood. Perhaps not as much as the term 'God' ... but it's not been around for quite as long and is doing its best to catch up.
If I mention science anywhere in this blog then this is what I mean. You may not agree with this definition, but it's the one I'm using and I'm the one doing the typing.
- Science is a set of well-defined models that can be tested against observation.
That's it. Well almost. I'll expand a bit after this partial list of things that science is not:
- a list of absolute facts
- a system of belief
- the stuff that makes the universe work
- a conspiracy of wicked men trying to kill God
What do I mean by 'a model'? Tricky one. Something that looks a bit like the thing it is modelling but is simpler and easier to work with. A globe is a model of the earth. Gravity is a model of how things fall down. Euclidian geometry is a model of how shapes fit together. The important thing is that models are not the same as the things they are modelling. Physics is not 'how the universe works', physics is 'a model of how the universe works'.
What do I mean by 'well-defined'. Trickier one. Something is well-defined if somebody other than its inventor can understand it according to some shared language and rules. This is the difficult bit of science that can lead to impenetrable jargon and funny-looking equations. You can describe a scientific model in plain English; the short-hand simply allows you to state it in a lot fewer pages.
What do I mean 'can be tested against observation'. This bit should be self-explanatory. A scientific model should tell you 'stuff' about the 'thing' that it models. You need to be able to compare the stuff the model tells you with the stuff that you can observe directly from the thing itself. If you can't compare one with the other then it is not a very good model, is it?
THIS NEXT BIT IS IMPORTANT.
Scientific models and theories are not 'true' or 'false'. They are 'useful' or 'not useful' in particular contexts. That is, they either tell you something useful and accurate about the thing they are modelling, or they don't.
Example 1: the world is flat
Hopefully everybody reading this thinks the above statement is 'false'. However, it is the model of the world used by the architects and engineers designing almost every building on the planet. Because it is useful in that context.
Example 2: Newtonian or Classical mechanics
This is an 'old' model of how objects move and interact. It is perfectly useful in almost all human-scale contexts. You can put a man on the moon with Newtonian mechanics. However, there are things that we observe about the universe that do not look like the Newtonian model. So we have to think up a new model that matches these observations. This does not make the model FALSE, it simply means it has a finite utility. It doesn't model everything.
The job of science is to test the models it has already invented until they break. And then invent some new ones to pick up the pieces.
When people dismiss science with the argument that 'science often gets things wrong' they are only partly correct. Science always gets things wrong. That's how science works.
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