 With respect to the problem of specifying probability distributions over possible values of physical parameters discussed in  Section 2.1  naturalness may be taken to suggest that all reasonable such distributions have most of their probabilistic weight close to the natural values. As explained, for the Higgs mass and the cosmological constant the natural values are much larger than the observed ones. Advocates of the view that fine-tuning for life requires a response because life-friendly constants are improbable therefore put particular emphasis on those instances of fine-tuning for life that are associated with violations of naturalness, notably the cosmological constant (e.g., Susskind 2005: ch. 2; Donoghue 2007; Collins 2009: sect. 2.3.3; Tegmark 2014: 140f.).