1. Wittgenstein's philosophical purpose vis-à-vis the sceptic in OC is a matter of dispute. He has variously been held to refute scepticism, by showing it is self-defeating; to reveal the truth in scepticism and to offer an accommodation with it; and to diagnose the misconceptions that underlie sceptical doubt, which does not itself constitute a refutation of scepticism but which opens up the way to our liberating ourselves from its philosophical grip. These three approaches to interpreting the remarks collected in OC do not, I’m sure, amount to an exhaustive classification of the interpretations put forward in the secondary literature. However, they do at least represent three importantly distinct ways of responding to scepticism that have been attributed to Wittgenstein, and this invites the question whether, on any of these interpretations, Wittgenstein's notes contain the makings of a philosophically satisfactory response to philosophical scepticism.

2. It may seem, prima facie, that the interpretation that offers the best hope of a philosophically satisfactory response to scepticism is one that holds that Wittgenstein's remarks contain a demonstration that scepticism is self-refuting. This approach promises to show that there simply is no intelligible doubt that needs to be removed before our ordinary knowledge claims can count as legitimate. Avrum Stroll defends an interpretation along these lines. He argues that Wittgenstein's remarks present a non-conventional and unique form of foundationalism. The idea is that the foundations of human knowledge do not themselves belong to the category of things that are known. The propositions that belong to the foundation are called ‘hinge propositions’, and they are exempt from epistemic evaluation. Our attitude towards what lies at the foundation of knowledge is a form of non-epistemic certainty, a form of sureness, which, Stroll claims, is not the product of ratiocination but ‘is something primitive, instinctual, or animal’, a way of acting that ‘derives from rote training in communal practices’ (Stroll 1994: 157). By means of training in communal practices, we inherit a picture of the world, which is expressed not merely in how we think about the world but in how we live and act; our picture of the world constitutes the framework within which all ordinary doubt and enquiry, all ordinary confirmation and disconfirmation of belief, take place.