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I thank R. B. Laughlin for a stimulating discussion that helped me form the superspin concept and T. M. Rice for a stimulating discussion that led to the identification of the triplet magnetic excitation of the quantum-disordered phase with the π triplet mode of the SC phase. I thank J. R. Schrieffer S. Kivelson R. B. Laughlin and D. Scalapino for patiently teaching me about various aspects of the high- T c problem throughout the years and for sharing with me their deep insights and enthusiasm and C. P. Burgess and C. Lütken for tutoring me about the nonlinear σ model theory of QCD. Inspiring discussions with N. Bulut E. Demler H. Fukuyama M. Greiter W. Hanke B. Keimer H. Kohno S. Meixner N. Nagaosa and Z. X. Shen are also gratefully acknowledged. Last but not least I thank C. N. Yang for collaborating on an earlier work which inspired the current one and for impressing me with the power of symmetry. Supported by the NSF under grants DMR-9400372 and DMR-9522915. Part of this work was carried out while visiting the IBM Almaden Research Center and I thank B. A. Jones for the hospitality extended to me during my visit.