I have updated and reorganized my collection of quotations. Here are links to them.
John Adams
John Quincy Adams
Alexander the Great
Muhammad Ali
Gracie Allen
James Allen
Woody Allen
Maya Angelou
Thomas Aquinas
Aristotle
Mary Kay Ash
Isaac Asimov
Augustine of Hippo
Marcus Aurelius
Jane Austen
Francis Bacon
Roger Bacon
Honore de Balzac
Dave Barry
Charles Baudelaire
Ludwig van Beethoven
Alexander Graham Bell
Milton Berle
Bias of Priene
Allan Bloom
Boethius
Niels Bohr
Erma Bombeck
Dietrich Bonhoeffer
Daniel Boone
Daniel Boorstin
Robert Bork
Emily Bronte
Mel Brooks
Phillips Brooks
Elizabeth Barrett Browning
Robert Browning
William Jennings Bryan
William Cullen Bryant
Martin Buber
William F. Buckley
Frederick Buechner
Warren Buffett
Rudolf Bultmann
John Bunyan
Edmund Burke
Carol Burnett
Samuel Butler
Robert Byrne
Albert Camus
George Carlin
Thomas Carlyle
Andrew Carnegie
Dale Carnegie
George Washington Carver
Marcus Porcius Cato
Dick Cavett
Miguel de Cervantes
J. Wilbur Chapman
Anton Chekhov
Gilbert Keith Chesterton
Oswald Chambers
John Chrysostom
Winston Churchill
Cicero
Bill Clinton
Samuel Taylor Coleridge
Charles Colson
Confucius
Joseph Conrad
Calvin Coolidge
James Fenimore Cooper
Stephen Covey
Noel Coward
W.A. (Wally Amos) Criswell
Marie Curie
Cyprian
Dante Alighieri
Clarence Darrow
Charles Robert Darwin
Richard Dawkins
James Dean
Demosthenes
Jacques Derrida
Rene Descartes
Simone de Beauvoir
Emily Dickinson
Phyllis Diller
Benjamin Disraeli
John Donne
Fyodor Dostoevsky
Will Durant and Ariel Durant
Thomas Edison
Jonathan Edwards
Albert Einstein
Dwight D. Eisenhower
George Eliot
T.S. (Thomas Stearns) Eliot
Jim Elliot
Havelock Ellis
Ralph Waldo Emerson
Friedrich Engels
Epicurus
Desiderius Erasmus
Euripides
Frederick W. Faber
Henry Fielding
W. C. Fields
Ella Fitzgerald
Malcolm Forbes
Henry Ford
Francis of Assisi
Francis of Sales
Benjamin Franklin
Frederick the Great
Sigmund Freud
Kinky Friedman
Erich Fromm
Robert Frost
Thomas Fuller
John Kenneth Galbraith
Mahatma Gandhi
James Garfield
Bill Gates
Khalil Gibran
William Gladstone
Johan Wolfgang von Goethe
Barry Goldwater
Baltasar Gracian
Billy Graham
Ulysses S. Grant
Wayne Gretzky
Andy Griffith
Buddy Hackett
Babs Hajdusiewicz
Paul Harvey
Georg Wilhelm Friedrich Hegel
Robert Heinlein
Ernest Hemingway
Matthew Henry
Patrick Henry
Heraclitus
George Herbert
Howard Hendricks
Napolean Hill
Rabbi Hillel
Alfred Hitchcock
Thomas Hobbes
Eric Hoffer
Oliver Wendell Holmes
Herbert Hoover
Horace
Fred Hoyle
Victor Hugo
David Hume
Zora Neale Hurston
John Hus
Aldous Huxley
Thomas H. Huxley
Irenaeus
Isocrates
Andrew Jackson
William James
Thomas Jefferson
Jerome
Lyndon B. Johnson
Juvenal
Helen Keller
Thomas a’ Kempis
John F. Kennedy
Soren Aabye Kierkegaard
Martin Luther King, Jr.
Charles Kingsley
Rudyard Kipling
Francois De La Rochefoucauld
Harper Lee
Robert E. Lee
Clives Staples Lewis
Abraham Lincoln
Art Linkletter
Walter Lippmann
D. Martyn Lloyd-Jones
Vince Lombardi
Henry Wadsworth Longfellow
Martin Luther
Erwin Lutzer
Douglas MacArthur
John MacArthur
Eugene McCarthy
George MacDonald
Josh McDowell
J. Gresham Machen
Nicholi Machiavelli
Nelson Mandela
Og Mandino
J. Willard Marriott
George Marshall
Groucho Marx
W. Somerset Maugham
John Maxwell
Henrietta Mears
Henry Louis Mencken
F. B. Meyer
John Stuart Mill
John Milton
Michel de Montaigne
Dwight L. Moody
Thomas Moore
G. Campbell Morgan
Mother Teresa
Malcolm Muggeridge
Andrew Murray
Napoleon Bonaparte
Ronald Nash
Watchman Nee
Willie Nelson
John Henry Newman
Isaac Newton
John Newton
Flannery O’Connor
Thomas Paine
Dorothy Parker
Dolly Parton
Blaise Pascal
George S. Patton, Jr.
William Penn
H. Ross Perot
Pablo Picasso
Arthur Pink
John Piper
Titus Maccius Plautus
Edgar Allan Poe
Alexander Pope
Terry Pratchett
Publilius Syrus
Dave Ramsey
Ayn Rand
Sam Rayburn
Thomas B. Reed
Max I. Reich
John D. Rockefeller
Jim Rohn
Adrian Rogers
Will Rogers
Eleanor Roosevelt
Franklin D. Roosevelt
Theodore Roosevelt
Rita Rudner
John Ruskin
Bertrand Russell
Philip Graham Ryken
J. C. Ryle
Antoine de Saint Exupery
Carl Sagan
Jonas Salk
George Santayana
Dorothy Sayers
Lee Scarborough
Philip Schaff
Arthur Schopenhauer
Albert Schweitzer
Seneca
William Shakespeare
George Bernard Shaw
Gail Sheehy
B.F. Skinner
Socrates
Aleksandr Solzhenitsyn
Sophocles
Gerry Spence
Nancy Spiegelberg
Spinoza
R. C. Sproul
Charles Haddon Spurgeon
Joseph Stalin
Philip Dormer Stanhope
Caecilius Statius
Adlai Stevenson
Robert Louis Stevenson
Lee Strobel
Billy Sunday
Tacitus
Charles Maurice de Talleyrand-Périgord
Alfred Lord Tennyson
Terence (Publius Terentius Afer)
Teresa of Avila
Tertullian
William Makepeace Thackeray
Thales of Miletus
Helmut Thielicke
Henry David Thoreau
James Thurber
Alexis de Tocqueville
Alvin Toffler
Leo Tolstoy
R.A. Torrey
A. W. Tozer
Brian Tracy
Anthony Trollope
Harry Truman
Donald Trump
Harriet Tubman
Mark Twain (Samuel Langhorne Clemons)
Lao Tzu
Sun Tzu
Henry van Dyke
Voltaire
Kurt Vonnegut
Jane Wagner
Andy Warhol
Booker T. Washington
George Washington
Thomas Watson
John Wayne
Daniel Webster
Simone Weil
H.G. Wells
Oscar Wilde
Dallas Willard
Tennessee Williams
Douglas Wilson
Flip Wilson
Jonathan Winters
Frank Lloyd Wright
Henny Youngman
Zig Ziglar