“To those whose talents are above mediocrity, the highest subjects may be announced. To those who are below mediocrity, the highest subjects may not be announced.”
Source: The Analects, Chapter VI
Original
中人以上、可以語上也、中人以下、不可以語上也。
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Confucius 269
Chinese teacher, editor, politician, and philosopher -551–-479 BCRelated quotes

Reported in Josiah Hotchkiss Gilbert, Dictionary of Burning Words of Brilliant Writers (1895), p. 30.
Dictionary of Burning Words of Brilliant Writers (1895)

Explaining that he has excluded living performers. Preface, p. vi.
Everyman's Dictionary of Music (London: J. M Dent & Sons; 3rd ed. 1958)

Europe, Evangelization, and Civilizational Suicide https://www.catholicworldreport.com/2015/12/28/europe-evangelization-and-civilizational-suicide/ (December 28, 2015)

Source: The Life of St. Teresa of Jesus (c.1565), Ch. XXV. "Divine Locutions. Discussions on That Subject" ¶ 22 & 23
Context: All things fail; but Thou, Lord of all, never failest! They who love Thee, oh, how little they have to suffer! oh, how gently, how tenderly, how sweetly Thou, O my Lord, dealest with them! Oh, that no one had ever been occupied with any other love than Thine! It seems as if Thou didst subject those who love Thee to a severe trial: but it is in order that they may learn, in the depths of that trial, the depths of Thy love. O my God, oh, that I had understanding and learning, and a new language, in order to magnify Thy works, according to the knowledge of them which my soul possesses! Everything fails me, O my Lord; but if Thou wilt not abandon me, I will never fail Thee. Let all the learned rise up against me, — let the whole creation persecute me, — let the evil spirits torment me, — but do Thou, O Lord, fail me not; for I know by experience now the blessedness of that deliverance which Thou dost effect for those who trust only in Thee. In this distress, — for then I had never had a single vision, — these Thy words alone were enough to remove it, and give me perfect peace: "Be not afraid, my daughter: it is I; and I will not abandon thee. Fear not."
It seems to me that, in the state I was in then, many hours would have been necessary to calm me, and that no one could have done it. Yet I found myself, through these words alone, tranquil and strong, courageous and confident, at rest and enlightened; in a moment, my soul seemed changed, and I felt I could maintain against all the world that my prayer was the work of God. Oh, how good is God! how good is our Lord, and how powerful! He gives not counsel only, but relief as well. His words are deeds. O my God! as He strengthens our faith, love grows.

“Mediocrity knows nothing higher than itself; but talent instantly recognizes genius.”
Source: The Valley of Fear

On Canadian author John Ralston Saul
"The world according to Conrad Black", 2007

In a letter to Sir Seymour Hicks (December 1910)

Source: An Introduction to Medical Literature, Including a System of Practical Nosology (1823), p. 2