Does scepticism threaten our common sense picture of the world? Does it really undermine our deep-rooted certainties? This book offers an answer to these questions through a comparative study of the epistemological work of two key figures in the history of analytic philosophy: G. E. Moore and Ludwig Wittgenstein. While historically accurate and engaging with scholarly work in this area, the book also puts forward novel interpretations of their works and brings out their relevance to present-day debates both in epistemology and philosophy of language.