If you can't explain what you are doing to a nine-year-old, then either you still don't understand it very well, or it's not all that worthwile in the first place.
The aim of science is, on the one hand, as complete a comprehension as possible of the connection between perceptible experiences in their totality, and, on the other hand, the achievement of this aim by employing a minimum of primary concepts and relations.
Arrows of hate have been aimed at me too, but they have never hit me, because somehow they belonged to another world with which I have no connection whatsoever.
For the moral attitudes of a people that is supported by religion need always aim at preserving and promoting the sanity and vitality of the community and its individuals, since otherwise this community is bound to perish. A people that were to honour falsehood, defamation, fraud, and murder would be unable, indeed, to subsist for very long.
Physics is an attempt conceptually to grasp reality as something that is considered to be independent of its being observed. In this sense one speaks of physical reality.
e idea of a personal God is quite alien to me and seems even naive. However, I am also not a "Freethinker" in the usual sense of the word because I find that this is in the main an attitude nourished exclusively by an opposition against naive superstition. My feeling is insofar religious as I am imbued with the consciousness of the insuffiency of the human mind to understand deeply the harmony of the Universe which we try to formulate as "laws of nature." It is this consciousness and humility I miss in the Freethinker mentality. Sincerely yours, Albert Einstein.