Lettre d'Albert Einstein à Louis de Broglie - 15 février 1954 (2)

Page 2 …/ formal principle (general covariance), i.e. based on the trust in the greatest conceivable logical simplicity of the laws of nature. Since it was clear that gravitational theory is only the first step toward finding general field laws that are as simple as possible, it seemed to me that this logical path must be thought through before one can hope to arrive at a solution to the quantum problem as well. As a result, I became a fanatical believer in the method of "logical simplicity." The physicists of this generation are now convinced that such a way cannot lead to the theory of atomistic and quantum structure. Maybe they are right about that. Maybe there is no quantum field theory, for my efforts cannot solve the problem of atomics and quanta, and may not even bring us closer to a solution. However, this negative belief is based solely on intuition, and not objectivity. I also see no other clear path to a logical simple theory. This explains the head-in-the-sand effect. I thought this might interest you from a psychological point of view, especially as you have lost confidence in the finality of the statistical method once more. With cordial regards. Yours, Signature of AE For your convenience, I enclose a French translation of this letter.