EINSTEIN, Albert (1879-1955). Autograph letter signed ("A.E.") to Michele Besso, [Princeton], 20 March 1952.

In German, one page, 279 x 214mm (damaged by waterstaining). Envelope.

On the interplay of intuition and logic in scientific theory. "Extensive factual materials are indispensable for the establishment of a promising theory. These materials in themselves however provide no point of departure for a deductive theory; under the effect of these materials one can however succeed in 'satisfying' a general principle which in itself can serve as the point of departure for a logical (deductive) theory. There is however no logical path which leads from the empirical material to the general principle on which the logical deduction is then based." Einstein continues: "In general one can say as follows: the path from the specific to the general is intuitive, the path from the general to the specific is logical."