The mathematics is not there till we put it there.

Man is slightly nearer to the atom than to the star. ... From his central position man can survey the grandest works of Nature with the astronomer, or the minutest works with the physicist. ... [K]nowledge of the stars leads through the atom; and important knowledge of the atom has been reached through the stars.

In Einstein's theory of relativity the observer is a man who sets out in quest of truth armed with a measuring-rod. In quantum theory he sets out with a sieve.

It is also a good rule not to put overmuch confidence in the observational results that are put forward until they are confirmed by theory.

If someone points out to you that your pet theory of the universe is in disagreement with Maxwell's equations - then so much the worse for Maxwell's equations. If it is found to be contradicted by observation - well, these experimentalists do bungle things sometimes. But if your theory is found to be against the second law of thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation.

In any attempt to bridge the domains of experience belonging to the spiritual and physical sides of nature, time occupies the key position.

I ask you to look both ways. For the road to a knowledge of the stars leads through the atom; and important knowledge of the atom has been reached through the stars.