Man's urge for change and his need for stability have always balanced and checked each other, and our current vocabulary, which distinguishes between two factions, the progressives and the conservatives, indicates a state of affairs in which this balance has been thrown out of order. No civilization - the man-made artifact to house successive generations - would ever have been possible without a framework of stability, to provide the wherein for the flux of change. Foremost among the stabilizing factors, more enduring than customs, manners and traditions, are the legal systems that regulate our life in the world and our daily affairs with each other.