"Metaphysical Pluralism" is an analysis of the conditions and causes for the multiplicity of metaphysical systems. It argues for the viability of metaphysical pluralism - the view that there is more than one plausible metaphysical system, and that there can be good reasons for these various views. Without arguing a specific theory of metaphysics, this thesis defends the ability of metaphysical knowledge to remain critical and rational in the face of the sceptical claim of relativism. Chapter One and the Appendix discuss the more general issues of conceptual pluralism as found in the social sciences. Ideas of autonomy and relativism from Wittgenstein and Winch are criticized, and it is concluded that there is no a priori guarantee that conceptual schemes are free from internal confusions, have determinate boundaries or exist in a fully developed and formal way. These conclusions are then applied to specific issues in the philosophical arguments of metaphysical systems. Chapters Two and Three do this. The historical conditions which develop into pluralism are described in Chapter Four as a permanent feature of the human condition and of knowledge as such. Chapter Five then explains how ultimate pluralism does not destroy the rationality or the purpose of a metaphysical framework, although any form of absolute, context free know edge is denied. Pluralism is interpreted and defended as a mid-point between relativism and absolutism, emphasizing both the constitutive character of conceptual schemes and the larger context of motives and values.