Book excerpt: This book offers an extraordinary interpretation of world history, from the paleolithic era to the present. Renowned historian L.S. Stavrianos conceptualizes human history into three categories: kinship societies, tributary societies, and capitalist societies. In each, he discerns and studies four "life-line" issues - ecology, gender relations, social relations, and war - that encompass the broadest areas of human experience. The revised edition projects forward to the twenty-first century, offering the author's views on possible future scenarios involving the same lifeline issues.