We have found that where science has progressed the farthest, the mind has but regained from nature that which the mind put into nature.

The physical world is entirely abstract and without actuality apart from its linkage to consciousness.

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.

So far as physics is concerned, time's arrow is a property of entropy alone.

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.

It cannot be denied that for a society which has to create scarcity to save its members from starvation, to whom abundance spells disaster, and to whom unlimited energy means unlimited power for war and destruction, there is an ominous cloud in the distance though at present it be no bigger than a man's hand.

A hundred thousand million Stars make one Galaxy; A hundred thousand million Galaxies make one Universe. The figures may not be very trustworthy, but I think they give a correct impression.