Enthusiasm originally meant inspiration or possession by a divine afflatus or by the presence of a God. Johnson's Dictionary, the first comprehensive dictionary of the English language, divines enthusiasm as "a vain belief of private revelation; a vain confidence of divine favour or communication." In current English vernacular the word simply means intense enjoyment, interest, or approval.

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• Whenever the true objects of action appear, they are to be heartily sought. Enthusiasm is the height of man; it is the passing from the human to the divine.
  • Ralph Waldo Emerson, in "The Superlative" in The Century (February 1882)

• The Greeks have given us one of the most beautiful words of our language, the word "enthusiasm" — a God within. The grandeur of the acts of men are measured by the inspiration from which they spring. Happy is he who bears a God within.
  • Louis Pasteur, as quoted in Spiritual Literacy : Reading the Sacred in Everyday Life (1998) by Frederic Brussat and Mary Ann Brussat

• There is real magic in enthusiasm. It spells the difference between mediocrity and accomplishment. ... It gives warmth and good feeling to all your personal relationships.
  • Norman Vincent Peale, as quoted in Spiritual Literacy : Reading the Sacred in Everyday Life (1998) by Frederic Brussat and Mary Ann Brussat

Dictionary of Burning Words of Brilliant Writers (1895)

Reported in Josiah Hotchkiss Gilbert, Dictionary of Burning Words of Brilliant Writers (1895).

• Enthusiasm is the element of success in every thing. It is the light that leads, and the strength that lifts men on and up in the great struggles of scientific pursuits and of professional labor. It robs endurance of difficulty, and makes a pleasure of duty.
  • Bishop Doane, p. 208.

• Every great and commanding movement in the annals of the world is the triumph of enthusiasm.
  • Ralph Waldo Emerson, p. 208.

• Those who have arrived at any very eminent degree of excellence in the practice of an art or profession have commonly been actuated by a species of enthusiasm in their pursuit of it. They have kept one object in view amidst all the vicissitudes of time and fortune.
  • John Knox, p. 208.

• In the whole range of human vision, nothing is more attractive than to see a young^ man full of promise and of hope, bending all his energies in the direction of truth and duty and God, his soul pervaded with the loftiest enthusiasm, and his life consecrated to the noblest ends. To be such a young man is to rival the noblest and best of men in heroic valor and Christian chivalry. Nay, to be such a young man is to be like Christ, the highest type, the most illustrious example of enthusiasm the world has ever seen.
  • John McClellan Holmes, p. 208.

• Be not afraid of enthusiasm; you need it; you can do nothing effectually without it.
  • François Guizot, p. 209.

• Depend upon it, my younger brethren, the bright, self-sacrificing enthusiasms of early manhood are among the most precious things in the whole course of human life.
  • Henry Parry Liddon, p. 209.

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• Every production of genius must be the production of enthusiasm.
  • Benjamin Disraeli

• Let us recognize the beauty and power of true enthusiasm; and whatever we may do to enlighten ourselves and others, guard against checking or chilling a single earnest sentiment.
  • Tuckerman

• Nothing is so contagious as enthusiasm; it moves stones, it charms brutes. Enthusiasm is the genius of sincerity, and truth accomplishes no victories without it.
  • Lytton

• The most enthusiastic man in a cause is rarely chosen as a leader.
  • Arthur Helps

• Let us beware of losing our enthusiasms. Let us ever glory in something, and strive to retain our admiration for all that would ennoble, and our interest in all that would enrich and beautify our life.
  • Phillips Brooks