Willam Bernstein is a renowned financial theorist, and a Co-Founder of the investment management firm Efficient Frontier

Advisors. He has authored three finance books, The Intelligent Asset Allocator, The Four Pillars of Investing, and The Investor's Manifesto,

and also two volumes of economic history, The Birth of Plenty and A Splendid Exchange. His research is in the field of modern portfolio theory,

and he argues that most return is determined by the asset allocation of a portfolio rather than by asset selection. Mr. Bernstein holds a PhD

in chemistry from the University of California at Berkeley and an MD from UC San Francisco. He practiced neurology for many years before

retiring to pursue finance.