Quotes about preparation

Source: The Hiding Place

As quoted in The Wilson Era; Years of War and After, 1917–1923 (1946) by Josephus Daniels, p. 624. Referenced in "Bartleby.com" http://www.bartleby.com/73/1288.html
1920s and later

This is a paraphrase of an idea that Dewey expressed using other words in My Pedagogic Creed (1897) and Democracy and Education (1916); it is widely misattributed to Dewey as a quotation.
Cf. James William Norman, A Comparison of Tendencies in Secondary Education in England and the United States (New York: Teachers College, Columbia University, 1922), [//books.google.com/books?id=qrmgAAAAMAAJ&pg=PA140 p. 140] (emphasis added): "...there has for years been a strong and growing tendency in the United States under the leadership of Dewey, and more recently of Kilpatrick, to find an educational method correlative of democracy in society with the belief that education is life itself rather than a mere preparation for life, and that practice in democratic living is the best preparation for democracy."
Misattributed
Variant: Education is a social process; education is growth; education is not preparation for life but is life itself.

Speech at Founding Rally of the Organization of Afro-American Unity (28 June 1964), as quoted in By Any Means Necessary (1970)
By any means necessary: speeches, interviews, and a letter (1970)
Variant: The future belongs to those who prepare for it today.
Source: Malcolm X, Black Liberation, and the Road to Workers' Power
Context: Education is an important element in the struggle for human rights. It is the means to help our children and our people rediscover their identity and thereby increase their self respect. Education is our passport to the future, for tomorrow belongs only to the people who prepare for it today.

Sometimes erroneously prepended to the opening line "The art of war is of vital importance to the State", but appears to be a variation of the Roman motto "Si vis pacem, para bellum". It's not clear who first misattributed this phrase to Sun Tzu. The earliest appearance of the phrase in Google Books is 1920, when it appeared in a pharmaceutical journal, but no attribution was given then.
Misattributed

"The Man Who Would Be Queen" in Melody Maker (2 May 1981) http://www.queenarchives.com/index.php?title=Freddie_Mercury_-_05-02-1981_-_Melody_Maker.

About the role of J. Pierpont Morgan, and the failure of Tesla's "World System" project
My Inventions (1919)
Context: He had the highest regard for my attainments and gave me every evidence of his complete faith in my ability to ultimately achieve what I had set out to do. I am unwilling to accord to some small−minded and jealous individuals the satisfaction of having thwarted my efforts. These men are to me nothing more than microbes of a nasty disease. My project was retarded by laws of nature. The world was not prepared for it. It was too far ahead of time, but the same laws will prevail in the end and make it a triumphal success.

As quoted in [Richard Wortman, Scenarios of Power: From Alexander II to the abdication of Nicholas II, https://books.google.com/books?id=wGp4M2DzfMQC&pg=PA341, 1995, Princeton University Press, 0-691-02947-4, 341–]

Source: P.S. I Love You

Cyropaedia, 4th Century BC

“Well, then,” said Callias, “take a place; for the guests, though well fed, as you observe, on seriousness, are perhaps rather ill supplied with laughter.”
Symposium, 1.11-13

Leaf by Niggle (1945)

St. John Chrysostom, Homily 24 on the Epistle to the Romans [PG 60:626-27] https://www.patheos.com/blogs/davearmstrong/2017/10/contraception-early-church-teaching-william-klimon.html

L'art n'est pas chaste [...], on devrait l’interdire aux ignorants innocents, ne jamais mettre en contact avec lui ceux qui y sont insuffisamment préparés. Oui, l'art est dangereux. Ou s'il est chaste, ce n'est pas de l'art.
Quote by Antonina Vallentin (1963 [1957]), Picasso, p. 168.
1960s

Speech at Omaha Beach on the 40th Anniversary of D-Day http://www.reagan.utexas.edu/archives/speeches/1984/60684b.htm (6 June 1984)
1980s, First term of office (1981–1985)

Source: Scouting for Boys: A Handbook for Instruction in Good Citizenship

Bill Skarsgard on ‘IT’ and Tapping into His Fears to Create a Terrifying New Pennywise http://collider.com/bill-skarsgard-pennywise-it-movie-interview/#images (July 28, 2017)

?
Books, The Beggar, Volume IV: Die Before Dying (Hari-Nama Press, 2005)

Babur-Nama, translated into English by A.S. Beveridge, New Delhi reprint, 1979, pp. 574-75

Robertson Davies as quoted in The White Bedouin‎ (2007) by George Potter, p. 241
Misattributed

Interviewed by David Ewen in The Etude, 1941; cited from Josiah Fisk and Jeff Nichols (eds.) Composers on Music (Boston, MA: Northeastern Universities Press, 1997) pp. 235-6

Quoted in The Life of This World Is a Transient Shade by Abdul Malik Al-Qasim

The Ant and the Grasshopper.

"If his forces are united, separate them" is also interpreted: "If sovereign and subject are in accord, put division between them."
Source: The Art of War, Chapter I · Detail Assessment and Planning

As quoted in Lifetime Speaker's Encyclopedia (1962) by Jacob Morton Braude, p. 575.

Reflections on Gandhi (1949)
Source: In Front of Your Nose: 1945-1950

Source: Practical Ethics

Existencilism (2002)
Source: Wall and Piece

Source: The Ultimate Foundation of Economic Science (1962), Chapter 5: On Some Popular Errors Concerning the Scope and Method of Economics, § 9 : The Belief in the Omnipotence of Thought

Quoted from Lal, K. S. (1992). The legacy of Muslim rule in India. New Delhi: Aditya Prakashan. Chapter 1
Travels in Asia and Africa (Rehalã of Ibn Battûta)

Other

Source: Slapstick (1976), Ch. 48

De Re Militari (also Epitoma Rei Militaris), Book III, "Dispositions for Action"
Variant: Si vis pacem para bellum. ("If you want peace, prepare for war.")

Open letter to the Fourth Soviet Writers’ Congress (16 May 1967); as translated in Solzhenitsyn: A Documentary Record (1970) edited by Leopold Labedz (1970).

Source: A General View of Positivism (1848, 1856), p. 153

Presidential address to the AFPFL Supreme Council Session (August 1946)

1870s, Speech before the Pole-Bearers Association (1875)

The TB12 Method (Simon & Schuster, 2017), p. 10 https://books.google.it/books?id=tkk1DwAAQBAJ&pg=PA10.

Letter http://dwardmac.pitzer.edu/anarchist_archives/bakunin/letters/toherzenandogareff.html to Aleksandr Ivanovich Herzen and Ogareff from San Francisco (3 October 1861); published in Correspondance de Michel Bakounine (1896) edited by Michel Dragmanov

Source: Down and out in Paris and London (1933), Ch. 14

Chronicle of the Seeker by: Mahmud Kati

Endorsement of President Jimmy Carter's Education Program - Feb. 7, 1979.

Tract 83 http://anglicanhistory.org/tracts/tract83.html (29 June 1838).

Source: The Montessori Method (1912), Ch. 1 : A Critical Consideration of the New Pedagogy in its Relation to Modern Science, p. 7.
Context: To prepare teachers in the method of the experimental sciences is not an easy matter. When we shall have instructed them in anthropometry and psychometry in the most minute manner possible, we shall have only created machines, whose usefulness will be most doubtful. Indeed, if it is after this fashion that we are to initiate our teachers into experiment, we shall remain forever in the field of theory. The teachers of the old school, prepared according to the principles of metaphysical philosophy, understood the ideas of certain men regarded as authorities, and moved the muscles of speech in talking of them, and the muscles of the eye in reading their theories. Our scientific teachers, instead, are familiar with certain instruments and know how to move the muscles of the hand and arm in order to use these instruments; besides this, they have an intellectual preparation which consists of a series of typical tests, which they have, in a barren and mechanical way, learned how to apply.
The difference is not substantial, for profound differences cannot exist in exterior technique alone, but lie rather within the inner man. Not with all our initiation into scientific experiment have we prepared new masters, for, after all, we have left them standing without the door of real experimental science; we have not admitted them to the noblest and most profound phase of such study, — to that experience which makes real scientists.

Cassandra (1860)
Context: The great reformers of the world turn into the great misanthropists, if circumstances or organisation do not permit them to act. Christ, if He had been a woman, might have been nothing but a great complainer. Peace be with the misanthropists! They have made a step in progress; the next will make them great philanthropists; they are divided but by a line.
The next Christ will perhaps be a female Christ. But do we see one woman who looks like a female Christ? or even like "the messenger before" her "face", to go before her and prepare the hearts and minds for her?
To this will be answered that half the inmates of Bedlam begin in this way, by fancying that they are "the Christ."
People talk about imitating Christ, and imitate Him in the little trifling formal things, such as washing the feet, saying His prayer, and so on; but if anyone attempts the real imitation of Him, there are no bounds to the outcry with which the presumption of that person is condemned.

Antropologia Pedagogica (1910), translated as Pedagogical Anthropology (1913), p. 259.
Context: It seems as though a new epoch were in preparation, a truly human epoch, and as though the end had almost come of those evolutionary periods which sum up the history of the heroic struggles of humanity; an epoch in which an assured peace will promote the brotherhood of man, while morality and love will take their place as the highest form of human superiority. In such an epoch there will really be superior human beings, there will really be men strong in morality and in sentiment. Perhaps in this way the reign of woman in approaching, when the enigma of her anthropological superiority will be deciphered. Woman was always the custodian of human sentiment, morality and honour, and in these respects man always has yielded women the palm.

Speech at Founding Rally of the Organization of Afro-American Unity (28 June 1964), as quoted in By Any Means Necessary (1970)
By Any Means Necessary (1970)

Source: The Warrior Within : The Philosophies of Bruce Lee (1996), p. 77, spoken by Cord, the protagonist of the unproduced film The Silent Flute

To many people tend to ask questions that the possible answers to that question might cause anger, hurt, disappointment or displays a weakness that they never were aware of until they got the one answer they weren't prepared for. If you haven't considered that then you might want to refrain from asking it.

The motto Baden-Powell chose for the Scouting movement (1907)

As quoted in Trigger Events – How To Find Your Next Customer (2007) by Alen Majer, p. 22

Source: Dirk Gently's Holistic Detective Agency (1987)

Source: Jingo

Wooden only repeated a common aphorism (e.g. Interview on Charlie Rose, reported by Bill Walton), which was already in circulation as early as the 1920s, when he was a youth. http://www.google.com/search?hl=en&tbs=bks%3A1%2Ccdr%3A1%2Ccd_min%3AJan+1_2+1900%2Ccd_max%3ADec+31_2+1930&q=%22fail+to+prepare%22+%22prepare+to+fail%22
Misattributed

Attributed in Laura Haddock (1931), Steps Upward in Personality
Misattributed
Variant: I will study and get ready, and perhaps my chance will come.

Van Gogh, the Man Suicided by Society (1947)

Source: The Hiding Place

Source: The Fifth Elephant

Source: The Prophecy Answer Book

Source: Different Seasons

Variant: It usually takes more than three weeks to prepare a good impromptu speech.

Source: Unseen Academicals

Source: Daring Greatly: How the Courage to Be Vulnerable Transforms the Way We Live, Love, Parent, and Lead

My Day (1935–1962)
Source: This is My Story
Context: If man is to be liberated to enjoy more leisure, he must also be prepared to enjoy this leisure fully and creatively. For people to have more time to read, to take part in their civic obligations, to know more about how their government functions and who their officials are might mean in a democracy a great improvement in the democratic processes. Let's begin, then, to think how we can prepare old and young for these new opportunities. Let's not wait until they come upon us suddenly and we have a crisis that we will be ill prepared to meet. (5 November 1958)

Temi, Adso, i profeti e coloro disposti a morire per la verità, ché di solito fan morire moltissimo con loro, spesso prima di loro, talvolta al posto loro.
William of Baskerville http://books.google.com/books?id=XY2vXKsHbzIC&q="Fear+prophets+adso+and+those+prepared+to+die+for+the+truth+for+as+a+rule+they+make+many+others+die+with+them+often+before+them+at+times+instead+of+them"&pg=PA549#v=onepage
Source: The Name of the Rose (1980)

Source: Sourcery

Source: How to Stop Worrying and Start Living

Source: Storm Front

Source: Gifted Hands: The Ben Carson Story
Source: Gifted Hands: The Ben Carson Story (1990), p. 232

See You at the Top (2000)

Source: The Winner Stands Alone

Letter Seven (14 May 1904)
Letters to a Young Poet (1934)
Variant: For one human being to love another human being: that is perhaps the most difficult task that has been given to us, the ultimate, the final problem and proof, the work for which all other work is merely preparation.
Source: The Selected Poetry of Rainer Maria Rilke
Context: People have (with the help of conventions) oriented all their solutions toward the easy and toward the easiest side of the easy; but it is clear that we must hold to what is difficult; everything alive holds to it, everything in Nature grows and defends itself in its own way and is characteristically and spontaneously itself, seeks at all costs to be so and against all opposition. We know little, but that we must hold to what is difficult is a certainty that will not forsake us; it is good to be solitary, for solitude is difficult; that something is difficult must be a reason the more for us to do it.
To love is good, too: love being difficult. For one human being to love another: that is perhaps the most difficult of all our tasks, the ultimate, the last test and proof, the work for which all other work is but preparation.

Not by Twain, but from Edward Abbey's A Voice Crying In The Wilderness (1989).
Misattributed

Letter Ten (26 December 1908)
Letters to a Young Poet (1934)