The most decisive intellectual influence in Paul's life was his discovery, while in medical school, of a passion for economics. It started with two vast novels: Ayn Rand's "Atlas Shrugged" and Boris Pasternak's "Dr. Zhivago," a gift from his mother. Both books make a case for the threat that big government bureaucracies pose to creativity and liberty.
Later, he read his way into Austrian economics – the counterweight to Keynesian economic ideas that informed the New Deal. He read Friedrich Hayek's "The Road to Serfdom" – a book that influenced a generation of American conservatives – and especially Ludwig von Mises, a libertarian who extended the influence of the Austrian school of economics in the United States.
For the Austrian school, government intervention in free markets isn't a formula for long-term economic growth. Mises warned that over time it would cripple free markets and lead to state control. Free markets are always superior to a centrally planned economy, he wrote. Mises also advocated a non-inflationary gold standard – an idea that Paul has made his own in his 2007 book "The Case for Gold" and a forthcoming book "Pillars of Prosperity: Free Markets, Honest Money, Private Property."
In 1971, Paul and another local doctor closed their practices for a day and drove 60 miles to the University of Houston to hear Mises give one of his last lectures in the United States.