[Kepler] had to realize clearly that logical-mathematical theoretizing, no matter how lucid, could not guarantee truth by itself; that the most beautiful logical theory means nothing in natural science without comparison with the exactest experience. Without this philosophic attitude, his work would not have been possible.
There is no logical way to the discovery of these elemental laws. There is only the way of intuition, which is helped by a feeling for the order lying behind the appearance.
I cannot write in English, because of the treacherous spelling. When I am reading, I only hear it and am unable to remember what the written word looks like.
What a person thinks on his own without being stimulated by the thoughts and experiences of the other people is even in the best case rather paltry and monotonous.
We must remember that we do not observe nature as it actually exists, but nature exposed to our methods of perception. The theories determine what we can or cannot observe...Reality is an illusion, albeit a persistent one.