Harvard University Press, 1989). Duncan Kennedy, A Critique of Adjudication (Cambridge, Massachusetts: Harvard University Press, 1998). David Lyons, Ethics & The Rule of Law (Cambridge: Cambridge University Press, 1984). David Lyons, Moral Aspects of Legal Theory (Cambridge: Cambridge University Press, 1993). Neil MacCormick, Legal Reasoning and Legal Theory (Oxford: Oxford University Press, 1979). Joseph Raz, The Authority of Law (Oxford: Oxford University Press, 1983, reprint). Robert S. Summers, Instrumentalism and American Legal Theory (Ithaca, NY: Cornell University Press, 1982). Robert S. Summers, Lon Fuller (Stanford, CA: Stanford University Press, 1984). Roberto Mangabeira Unger, The Critical Legal Studies Movement (Cambridge, Massachusetts: Harvard University Press, 1986). Jeffrie G. Murphy and Jules L. Coleman, The Philosophy of Law: An Introduction to Jurisprudence'' (Boulder, CO: Westview Press, 1989). External links Internet Encyclopedia of Philosophy: Philosophy of Law Legal ethics Social philosophy Law