Postulate
A postulate (also sometimes called an axiom) is a statement that is agreed by everyone to be obvious and correct. This is useful for creating proofs in mathematics and science, and postulates are often the basic truth of a much larger theory or law.
Postulates themselves cannot be proven, but since they are usually obviously correct this is not a problem. Here is a good example of a postulate (given by Euclid in his studies about geometry).
- Two points determine (make) a line.
Using this postulate and four others like it, Euclid brought a new understanding of geometry to the world, and many people think they are some of the most influential works in geometry even now.
There are also a few characteristics that all postulates should have.
- They should be obvious and easy to understand, and should not have too many words that are difficult to explain.
- There should not be very many of them.
- They should all work together without making any strange results (they should be consistent).
- They should also be true when they are alone (so they can be used independently).
Postulates are sometimes proved to be wrong after they have been known for a long time, but this is usually because something new has been discovered, and the original creator could not have known any better.
