The two most important words Harry Markowitz ever wrote are "portfolio selection." In 1952, when everyone in the stock market was looking for the next hot stock, as a doctoral candidate, he proposed to look at many, diverse stocks--a portfolio. He laid the first cornerstone of Modern Portfolio Theory and defended the idea that strategic asset growth means factoring in the risk of an investment. More than 60 years later, the father of modern finance revisits his original masterpiece, describes how his theory has developed, and proves the vitality of his risk-return analysis in the current...