Direto ao ponto

"Models are only models, not the thing in itself. We cannot, therefore, expect them to be truly right. Models are better regarded as a collection of parallel thougth universes you can explore. Universe should be consistent, but the actual financial and human world, unlike the world of matter, is going to be infinitely more complex than any model we make of it. We are always trying to shoehorn the real world into one of the models to see how useful an approximation it is".

Emanuel Derman, My Life as a Quant

"It does take maturity to realize that models are to be used but not to be believed"

Henry Theil