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Fractals are beautiful mathematical contructs characterized by a never-ending cascade of similar structural details that are revealed upon magnification on all scales. Over the past two decades, the notion has been intensively put forward that fractal geometry describes well the irregular face of nature. But does it? Consider the recent Perspective in Science by Marder (1). Marder summarizes a simulation study of fractured silicon nitride by Kalia et al.(2) that successfully mimics experimental data, and he generally emphasizes the role of fractal geometry in describing physical structures of complex geometry. Specifically, the results of Kalia et al. were interpreted as “showing that this mechanism… leads to fractal fracture surfaces.” However, upon examining Kalia's results [figure 4 in (2)], one finds that Marder's statement is based on four exponents, all of which hold over less than one order of magnitude. A fractal object …