(FORTUNE Magazine) – In the morning on his way to work, J.P. Morgan is said to have visited an astrologer named Evangeline Adams, a descendant of John Adams. "Is it true that millionaires consult astrologers?" someone once asked Morgan. "No," the great financier-industrialist replied, "billionaires do."

Well, so does FORTUNE. Specifically, we recently perused The Secret Language of Birthdays, the hot-selling new-age book that makes the case that people born on the same day of the year share certain personality characteristics. The book's 366 "personology" profiles combine astrology, numerology, the tarot, and author Gary Goldschneider's observations on 14,000 contemporary and historical figures.

We wondered whether the personologies of well-known business people would match their personalities, so we found out their birthdays and checked them against the book's charts. Is the book accurate? You make the call. --Patricia Sellers

Donald Trump Real Estate Magnate June 14 The Day of Gutsy Confrontation Born on this day: Che Guevera, Steffi Graf Personality: Gutsy, Resilient. Arrogant. Vengeful. Capable of clever duplicity. Impatient. Advice: Avoid all forms of egotistical excess. Beware of dominating others.

Gerald Levin CEO, Time Warner May 6 The Day of Materialized Fantasy Born on this day: Sigmund Freud; Orson Welles Personality: Astute. Imaginative. Sensitive. Expert at guiding others through difficult times. Emotionally unstable. Advice: Keep a handle on our emotions. Get your house in order

Roger Enrico CEO, PepsiCo November 11 The Day of the Underground Born on This Day: George Patton, Alger Hiss Personality: Colorful. Energetic. Intense. Persuasive. Has talent for structuring professional organizations. Possessive. Troubled. Advice: Forget your own wishes occasionally. Accept what fate serves up.

Warren Buffett CEO, Berkshire Hathaway August 30 The Day of the Rock Born on this Day: Ted Williams, Huey Long, Jean-Claude Killy Personality: Extremely capable. Particularly good with money. Highly confident, self-possessed. Authoritarian. Advice: Beware of fostering dependency; teach your children to be self-sufficient.

Ted Turner Vice Chairman, Time Warner Jack Welch CEO, General Electric November 19 The Day of the Reformer Born on this day: Martin Luther King, Indira Gandhi, Calvin Klein Personality: Revolutionary. Pugnacious. Ruthlessly driven to succeed. Risk is tragic hubris Advice: Learn the value of silence

Michael Eisner CEO, Walt Disney March 7 The Day of Abstract Structure Born on this day: Piet Mondrian, Maurice Ravel, Ivan Lendl Personality: Imaginative. Sensitive. Lonely. Seems to live on a different plane. Very private away from work. Advice: Allow others into your world. Be extremely careful about your health.

Andy Grove CEO, Intel September 2 The Day of the Businesslike Attitude Born on this day: Peter Ueberroth, Jimmy Connors Personality: Fair. Honest. Has egalitarian view of the world. Tends toward workaholism. Unyielding. Advice: Allow for inspiration. Don't work for work's sake.

Robert Allen CEO, AT&T January 25 The Day of Destiny Born on this day: Virginia Woolf, Benedict Arnold Personality: Talented. Idealistic. Self-defeating. Unstable. Advice: Never give up. Don't let the dark side of you peronality do you in.

Bill Gates CEO, Microsoft October 28 The Day of Research Born on this day: Jonas Salk, Isaac Singer Personality: Financially shrewd. Sometimes unscrupulous. Demanding. Makes no distinction between career and private life. Advice: Cultivate the gentle side of your nature. Don't be so judgmental.

Rupert Murdoch CEO, News Corp. March 11 The of Progressive Intuition Born on this day: Antonin Scalia, Sam Donaldson Personality: Shrewd. Possessive. Domineering. Sees the world as a competitive place where only the quick and clever survive. Advice: Don't be too concerned with tangible goals. Cultivate spiritual development.

Michael Ovitz ex-President, Walt Disney December 14 The Day of the Selective Exhibitionist Born on this day: Margaret Chase Smith, Patty Duke Personality: Indomitable. Emotionally hard. Very complex. Seeks limelight but lets few people into their world. Advice: Be aware of social values and the feelings of others. Learn to compromise.