Originally Posted by

**Sanford**
Prof. Hawking said the world is like a goldfish bowl. Just as the fish knows only the bowl, we only know what we see. Hawking simply does not understand what science is, for him to make such a statement!

A science theory is based upon mathematics, which is a collection of arbitrary fully consistent statements. The theory must also agree somewhat with observations and experiments. The fish does not understand mathematics, as mathematics is a human creation, and so the fish does not have a scientific understanding of the world.

General Relativity is a valid theory, as the mathematics is consistent, and many observations (not all) agree with the theory. Quantum mechanics is also a valid theory. However, these conflict, as the mathematical assumptions are different. We can live with this conflict, as relativity deals with large objects like planets, and quantum mechanics deals with small objects like atoms. Currently, it is impossible to measure the gravitational force between two atoms, and so we cannot make an experiment to determine which theory is correct.

Hawking speaks a lot about the nature of the universe. Here he is out of his league. There is currently no theory of cosmology, that is, there is no consistent mathematical framework that agrees with observations. The reason is that current theories, general relativity and quantum mechanics conflict with each other, and both are needed for a correct explanation of cosmology. All discussions of cosmology, such as the Big Bang idea, are hypotheses, that is, guesses, not rigorous scientific theories. We must be careful not to confuse theories, which are rigorous explanations, with hypotheses, which are guesses hopefully paving the way to a theory.