1910s: Buddhism becomes popular in the West. Zen Buddhism is spread through the presentations of Japanese Zen leader D. T. Suzuki.

1950s: June 30, 1956, the phrase "In God We Trust" is adopted as the U.S. national motto. In the following year it begins to appear on U.S. paper currency. It was already in use on certain coins since 1864.

Today: Cardinal Francis Arinze, a Nigerian who is on the short list for candidates to succeed Pope John Paul II, travels around the world promoting inter-religious dialogue. He is the president of the Vatican's Pontifical Council for Interreligious Dialogue.

1910s: Sigmund Freud publishes his book The Interpretation of Dreams in English in 1913, and the first journal devoted to psychology, Journal of Applied Psychology, begins publishing in 1917.

1950s: In 1950, Alan M. Turing publishes his article "Computing Machinery and Intelligence" in the quarterly Mind, and the American...