Log In

Peter Lewyn Bernstein Edit Profile


Peter Lewyn Bernstein was an American financial historian, economist and educator whose development and refinement of the efficient-market hypothesis made him one of the country's best known authorities in popularizing and presenting investment economics to the general public.


A native of New York City, Peter Bernstein was the son of financial consultant Allen Bernstein and his wife, Irma Lewyn.

A longtime resident of Manhattan, Peter Bernstein was 90 years old when he died of pneumonia at NewYork-Presbyterian/Weill Cornell Hospital, after having broken a hip. His first wife, Shirley, died in 1971 and he is survived by his second wife, Barbara, whom he married in 1972.


His primary education was at the Ethical Culture School where, in first grade, he became a lifelong friend of another renowned economics historian, Robert Heilbroner, with whom he later attended Horace Mann School and Harvard College.

He satudied with Robert Heilbroner at Harvard College, from which both received, in 1940, bachelors degrees in economics. Following Harvard, where he was elected to Phi Beta Kappa and graduated magna cum laude, came service as a member of the research staff at the Federal Reserve Bank of New York and, in a civilian capacity, at the Office of Strategic Services in Washington.


In the aftermath of the December 7, 1941 Pearl Harbor attack, he joined the Air Force and rose to the rank of captain, assigned to the Office of Strategic Services in the European theater.

As investment manager

In 1951, after teaching economics at Williams College and a five-year stint in commercial banking, Bernstein took over, at family insistence, the management of his late father's wealth management firm, Bernstein-Macaulay Inc., where he personally managed billions of dollars of individual and institutional portfolios. The assets under his management had grown more than tenfold by the time the firm was sold in 1967 and he resigned in 1973 to launch Peter L. Bernstein, Inc. and, a year later, to become the first editor of the Journal of Portfolio Management, a widely-read scholarly financial publication for investment managers and academics. He continued as consulting editor of the Journal and served on the advisory panel of Robert D. Arnott's investment management firm, Research Affiliates.

Career as educator and lecturer

Bernstein served for many years on the Visiting Committee to the Economics Department at Harvard University, as a Trustee and member of the Finance Committee of the College Retirement Equities Fund (CREF), and as a Trustee of the Investment Management Workshop sponsored by the Association for Investment Management & Research (AIMR), and had been lecturing widely throughout the United States and abroad on risk management, asset allocation, portfolio strategy, and market history.


  • In his books he embraced and explained an investment strategy that came to be known as efficient market theory. Rather than just picking stocks because they seemed to be good bets, investors increasingly diversified their portfolios, using sophisticated mathematical equations, developed in academia, with the goal of measuring and managing risk. Peter Bernstein’s contribution was as an interpreter and communicator, and he certainly did popularize academic finance. The hope was that with diversification, the stock market would be less likely to collapse, although Mr. Bernstein worried that a collapse could occur. He was an advocate of more market regulation to prevent one. But he also argued that the wealth and entrepreneurial energy generated by a rising stock market were worth the risk. Mr. Bernstein was the founder, in 1973, of Peter L. Bernstein Incorporated, which published his newsletter and also had as clients wealthy families and foundations, helping them manage their wealth. A year later, he founded the Journal of Portfolio Management, a scholarly journal that brought traders and academics into communication with each other as they developed efficient market theory. In the last 25 years of Mr. Bernstein’s life, nearly all his work focused on markets. But he had cast a broader net earlier, particularly in his writings with the late Robert L. Heilbroner, a historian and the author of a classic economics book, “The Worldly Philosophers.” After the war, Mr. Bernstein taught at Williams College and then became a loan officer in a commercial bank in New York, learning about risk, he later explained, as he assessed the creditworthiness of the borrowers. Family pressure led him to Wall Street. After his father died in 1951, the family insisted that he take control of the father’s business, Bernstein-Macaulay Incorporated, a wealth management firm. It was sold in 1967 and Mr. Bernstein stayed on as manager until 1973, having agreed to do southern But he had already immersed himself in writing and scholarship, and from then on he focused on markets and risk, with occasional digressions. One of those was “Wedding of the Waters: The Erie Canal and the Making of a Great Nation” (W.W. Norton, 2005), in which he returned to public works spending.


  • book

    • Against The Gods: The Remarkable Story of Risk

    • Capital Ideas: The Improbable Origins of Modern Wall Street

    • Streetwise: The Best of The Journal of Portfolio Management

    • A Primer on Money, Banking and Gold


Allen Bernstein - American

financial consultant

Irma Lewyn - American