 An alternative criterion of naturalness—sometimes dubbed absolute naturalness (see Wells [2015] for an empirical motivation)—is that a theory is natural if and only if it can be formulated using dimensionless numbers that are all of order \(1\). More permissive is ’t Hooft’s technical naturalness criterion (’t Hooft 1980), according to which a theory is natural if it can be formulated in terms of numbers that are either of order \(1\) or very small but such that, if they were exactly zero, the theory would have an additional symmetry. The motivation for this prima facie arbitrary criterion is that it elegantly reproduces verdicts based on the above formulation of naturalness according to which low-energy phenomena should not depend sensitively on the details of some more fundamental theory with respect to high energies.