In this paper I discuss the role played by the ideas of ‘common sense’ and ‘common sense morality’ in Sidgwick’s system of ideas. I argue that, far from aiming at overcoming common sense morality, Sidgwick aimed purposely at grounding a consist code of morality by methods allegedly taken from the example provided by the natural sciences, in order to reach also in the moral field some body of ‘mature’ knowledge similar to that provided by the natural sciences. His whole polemics (...) with intuitionist was vitiated by the a priori assumption that the widespread ethos, not the theories of intuitionist philosophers was what was really worth considering In spite of the naïve positivist starting point Sidgwick was encouraged by his own approach in exploring the fruitfulness of coherentist methods for normative ethics. Thus Sidgwick left an ambivalent legacy to twentieth-century ethics: the dogmatic idea of a ‘new’ morality of a consequentialist kind, and the fruitful idea that in normative ethics we can argue rationally even though without shared foundations. (shrink)