Albert Einstein’s statement, “God does not play dice with the universe,” is often cited as proof that Einstein believed in God, as though, if he did, we should too. But I think that he was merely expressing his doubt about Heisenberg’s uncertainty principle, which states that you can’t know everything about matter on a very small scale. In particular, for an elementary particle, the more you know about its location the less you know about its velocity and vice versa.
Einstein later clarified his words, at least in private, as you can read in these excerpts:
“It was, of course, a lie what you read about my religious convictions, a lie which is being systematically repeated. I do not believe in a personal God and I have never denied this but have expressed it clearly. If something is in me which can be called religious then it is the unbounded admiration for the structure of the world so far as our science can reveal it.”— Albert Einstein, 1954, from Albert Einstein: The Human Side
“I see only with deep regret that God punishes so many of His children for their numerous stupidities, for which only He Himself can be held responsible; in my opinion, only His nonexistence could excuse Him.” — Albert Einstein, letter to Edgar Meyer, 1915 Jan. 2
“From the viewpoint of a Jesuit priest I am, of course, and have always been an atheist.” — Albert Einstein, letter to Guy H. Raner Jr, 1945 July 2
“I have repeatedly said that in my opinion the idea of a personal God is a childlike one.” — Albert Einstein, letter to Guy H. Raner Jr, 1949 Sept. 28
“The word God is for me nothing more than the expression and product of human weaknesses, the Bible a collection of honorable, but still primitive, legends which are nevertheless pretty childish.” — Albert Einstein