"When an English physicist seeks to construct a model appropriate enough to represent a group of physical laws, he is not embarrassed by any logical necessity. He does not aim to deduce his model from a philosophical system, nor even to put it into accord with such a system. He has only one object: to create a visible and palpable image of the abstract laws that his mind cannot grasp without the aid of this model."

(From The Aim and Structure of Physical Theory, Pierre Duhème, 1954)

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