CHAPTER 4

THE UNCERTAINTY PRINCIPLE

The success of scientific theories, particularly Newton's theory of gravity,

led the French scientist the Marquis de Laplace at the beginning of the nineteenth century to argue that the universe was completely deterministic.

Laplace suggested that there should be a set of scientific laws that would allow us to predict everything that would happen in the universe,

if only we knew the complete state of the universe at one time.

For example, if we knew the positions and speeds of the sun and the planets at one time,

then we could use Newton's laws to calculate the state of the Solar System at any other time.

Determinism seems fairly obvious in this case,

but Laplace went further to assume that there were similar laws governing everything else,