 The need for philosophers to address the problem of the external world was widely regarded as a legacy of early modern philosophy to the nineteenth and twentieth centuries. At Cambridge and Oxford into the 1890s, discussions of the problem of the external world referenced Hamilton’s Lectures on Metaphysics (1861) and J. S. Mill’s An Examination of Sir William Hamilton’s Philosophy (1872). In that decade and the next, G. F. Stout and James Ward at Cambridge discussed the problem as did Thomas Case and John Cook Wilson at Oxford (Nasim 2008, Hatfield 2013b).