Nor is the failure of an empirical prediction, even a central one, in itself enough to explain the abandonment of the Levy model. As we saw in chapter 2, the Capital Asset Pricing Model made, at least once Sharpe had the confidence to embrace it, a prediction that was manifestly false that all investors would hold portfolios of risky assets that were identical in their proportionate composition but that did not stop the model being adopted widely. What was at least as important as the empirical doubt cast on self-similarity or invariance under addition in explaining the abandonment of the hypothesis of Levy distributions was that a variety of other ways of modeling distributions with high frequencies of extreme events were becoming available (see, for example, Clark 1973).

Donald MacKenzie, An Engine, Not a Camera, loc. 514