Deep quotes
page 2

“It does not matter how slowly you go as long as you do not stop.”

“There is another world, but it is in this one.”
Il y a assurément un autre monde, mais il est dans celui-ci...
Œuvres complètes, vol. 1, Gallimard, 1968.

“God is a comedian playing to an audience too afraid to laugh.”
"Creator — A comedian whose audience is afraid to laugh." — H.L. Mencken, A Book of Burlesques (1920), p. 203. and A Mencken Chrestomathy (1949), Ch. 30
Misattributed

“Even if I knew that tomorrow the world would go to pieces, I would still plant my apple tree.”
Martin Luther
Misattributed

“And in the end, it’s not the years in your life that count. It’s the life in your years.”
This quote is often misattributed to Lincoln. The earliest instance that Quote Investigator could locate was "in an advertisement in 1947 for a book about aging by Edward J. Stieglitz, M.D". The advertisement for “The Second Forty Years” which ran in the Chicago Tribune newspaper read like this: The important thing to you is not how many years in your life, but how much life in your years! (Compare 1947 March 16, Chicago Tribune, “How Long Do You Plan to Live?”, [Advertisement for the book "The Second Forty Years" by Edward J. Stieglitz, M.D.], p. C7, Chicago, Illinois. (ProQuest)). Source of misattribution: It’s Not the Years in Your Life That Count. It’s the Life in Your Years - Abraham Lincoln? Adlai Stevenson? Edward J. Stieglitz? Anonymous? by Quote Investigator on July 14, 2012 http://quoteinvestigator.com/2012/07/14/life-years-count/
To my way of thinking it is not the years in your life but the life in your years that count in the long run.
Adlai Stevenson II, Address at Princeton University, "The Educated Citizen" (22 March 1954) http://infoshare1.princeton.edu/libraries/firestone/rbsc/mudd/online_ex/stevenson/adlai1954.html. This has also been paraphrased "What matters most is not the years in your life, but the life in your years" and misattributed to Abraham Lincoln and Mae West.
Adlai Stevenson II, "If I Were Twenty-One" in Coronet (December 1955).
Misattributed
Variant: It is not the years in your life but the life in your years that counts.

Source: You Learn by Living (1960), p. 29–30
Context: You gain strength, courage and confidence by every experience in which you really stop to look fear in the face. You are able to say to yourself, "I have lived through this horror. I can take the next thing that comes along." … You must do the thing you think you cannot do.

“No act of kindness, no matter how small, is ever wasted.”
The Lion and the Mouse.
Variant: No act of kindness, no matter how small, is ever wasted.

“We may encounter many defeats but we must not be defeated.”

“We make a living by what we get, but we make a life by what we give.”

“It is not so much our friends' help that helps us, as the confidence of their help.”

“I have promises to keep and miles to go before I sleep.”
"Stopping by Woods on a Snowy Evening" (1923) http://www.poetryfoundation.org/poem/171621
Variant: And miles to go before I sleep.
Context: The woods are lovely, dark and deep.
But I have promises to keep,
And miles to go before I sleep,
And miles to go before I sleep.

“It’s no use going back to yesterday, because I was a different person then.”
Source: Alice in Wonderland

“In the long run, the sharpest weapon of all is a kind and gentle spirit.”
Source: The Diary of Anne Frank

“Each person must live their life as a model for others.”

" The Problem of Increasing Human Energy http://www.tfcbooks.com/tesla/1900-06-00.htm", Century Illustrated Magazine (June 1900)

As quoted in "Hand Book : Caution and Counsels" in The Common School Journal Vol. 5, No. 24 (15 December 1843) by Horace Mann, p. 371
Context: This is that which I think great readers are apt to be mistaken in; those who have read of everything, are thought to understand everything too; but it is not always so. Reading furnishes the mind only with materials of knowledge; it is thinking that makes what we read ours. We are of the ruminating kind, and it is not enough to cram ourselves with a great load of collections; unless we chew them over again, they will not give us strength and nourishment.

“When you want something, all the universe conspires in helping you to achieve it.”
E quando você quer alguma coisa, todo o Universo conspira para que você realize seu desejo.
Variant: And, when you want something, all the universe conspires in helping you to achieve it.
Source: The Alchemist (1988), p. 22; a variant of this has become attributed to Ralph Waldo Emerson: "Once you make a decision, the universe conspires to make it happen" — but no occurrence of this a statement has been located prior to in The Gift of Depression : Twenty-one Inspirational Stories Sharing Experience, Strength, and Hope (2001) by John F. Brown, p. 56

“If there's a book that you want to read, but it hasn't been written yet, then you must write it.”

“Life is not a problem to be solved, but a reality to be experienced.”
Attributed to Kierkegaard in a number of books, the earliest located on Google Books being the 1976 book Jack Kerouac: Prophet of the New Romanticism by Robert A. Hipkiss, p. 83 http://books.google.com/books?id=g_JaAAAAMAAJ&q=%22problem+to+be+solved%22#search_anchor. In the 1948 The Hibbert Journal: Volumes 46-47 the quote is referred to as "the famous Kierkegaardian slogan" on p. 237 http://books.google.com/books?id=UuDRAAAAMAAJ&q=%22the+famous+Kierkegaardian+slogan+life+is+not+a+problem+to+be+solved%22#search_anchor, which may be intended to suggest the phrase is Kierkegaard-esque rather than being something written by Kierkegaard. In reality this seems to be a slightly altered version of the quote "The mystery of life is not a problem to be solved; it is a reality to be experienced" which appeared in the 1928 book The Conquest of Illusion by Jacobus Johannes Leeuw, p. 9 http://books.google.com/books?id=OFdVAAAAMAAJ&q=%22not+a+problem+to+be+solved%22#search_anchor.
Misattributed

“It is during our darkest moments that we must focus to see the light.”

“I have never let my schooling interfere with my education.”
Variant: Never let your schooling interfere with your education.

“Success is not final, failure is not fatal: it is the courage to continue that counts.”
Attributed to Winston Churchill in The Prodigal Project : Book I : Genesis (2003) by Ken Abraham and Daniel Hart, p. 224 and other places, though no source attribution is given. It actually derives from an advertising campaign for Budweiser beer in the late 1930s.
Misattributed
Variant: Success is not final, failure is not fatal: it is the courage to continue that counts.
Source: http://quoteinvestigator.com/2013/09/03/success-final/

“Civilization is a hopeless race to discover remedies for the evils it produces.”

“When we strive to become better than we are, everything around us becomes better, too.”
Source: The Alchemist

“Do not go where the path may lead, go instead where there is no path and leave a trail.”

“Keep your eyes on the stars, and your feet on the ground.”
Variant: Look Toward the stars but keep your feet firmly on the ground.
Source: The Greatest American President: The Autobiography of Theodore Roosevelt

“All your life, you will be faced with a choice. You can choose love or hate…I choose love.”

“The trouble is, you think you have time.”
Source: Buddha's Little Instruction Book

“You who suffer because you love, love still more. To die of love, is to live by it.”
Source: Les Misérables

“You are what you believe yourself to be.”
Source: The Witch of Portobello (2007), p. 152.
Context: You are what you believe yourself to be.
Don't be like those people who believe in "positive thinking" and tell themselves that they're loved and strong and capable. You don't need to do that because you know it already. And when you doubt it — which happens, I think, quite often at this stage of evolution — do as I suggested. Instead of trying to prove that you're better than you think, just laugh. Laugh at your worries and insecurities. View your anxieties with humor. It will be difficult at first, but you'll gradually get used to it. Now go back and meet all those people who think you know everything. Convince yourself that they're right, because we all know everything, it's merely a question of believing.
Believe.

“How wonderful it is that nobody need wait a single moment before starting to improve the world.”
Source: Anne Frank's Tales from the Secret Annex

“What seems to us as bitter trials are often blessings in disguise”

“The best way to predict your future is to create it.”

“Genius is the recovery of childhood at will.”

“The problem is not to find the answer, it's to face the answer”

“Everything that irritates us about others can lead us to an understanding of ourselves.”
ii. America: The Pueblo Indians http://books.google.com/books?id=w6vUgN16x6EC&printsec=frontcover&dq=Jung+Memories+Dreams+and+Reflections&hl=en&sa=X&ei=LLxKUcD0NfSo4APh0oDABg&ved=0CDAQ6AEwAA#v=onepage&q&f=false (Extract from an unpublished ms) (Random House Digital, 2011).
Memories, Dreams, Reflections (1963)
Context: We always require an outside point to stand on, in order to apply the lever of criticism. This is especially so in psychology, where by the nature of the material we are much more subjectively involved than in any other science. How, for example, can we become conscious of national peculiarities if we have never had the opportunity to regard our own nation from outside? Regarding it from outside means regarding it from the standpoint of another nation. To do so, we must acquire sufficient knowledge of the foreign collective psyche, and in the course of this process of assimilation we encounter all those incompatibilities which constitute the national bias and the national peculiarity. Everything that irritates us about others can lead us to an understanding of ourselves. I understand England only when I see where I, as a Swiss, do not fit in. I understand Europe, our greatest problem, only when I see where I as a European do not fit into the world. Through my acquaintance with many Americans, and my trips to and in America, I have obtained an enormous amount of insight into the European character; it has always seemed to me that there can be nothing more useful for a European than some time or another to look out at Europe from the top of a skyscraper. When I contemplated for the first time the European spectacle from the Sahara, surrounded by a civilization which has more or less the same relationship to ours as Roman antiquity has to modem times, I became aware of how completely, even in America, I was still caught up and imprisoned in the cultural consciousness of the white man. The desire then grew in me to carry the historical comparisons still farther by descending to a still lower cultural level.
On my next trip to the United States I went with a group of American friends to visit the Indians of New Mexico, the city-building Pueblos...

“Too many of us are not living our dreams because we are living our fears.”
Variant: Too many of us are not living our dreams because we are living out fears.

“you'll miss the best things if you keep your eyes shut”
Source: I Can Read With My Eyes Shut! (1978)

“Keep your face always toward the sunshine – and shadows will fall behind you.”
This has become attributed to both Walt Whitman and Helen Keller, but has not been found in either of their published works, and variations of the quote are listed as a proverb commonly used in both the US and Canada in A Dictionary of American Proverbs (1992), edited by Wolfgang Mieder, Kelsie B. Harder and Stewart A. Kingsbury.
Misattributed

“No matter where you go, there you are”
Source: When You Come to a Fork in the Road, Take It!: Inspiration and Wisdom from One of Baseball's Greatest Heroes

“Life is what you make it. Always has been, always will be.”

“Every man is born as many men and dies as a single one.”
“The secret of your future is hidden in your daily routine.”
Source: The Road Less Traveled: A New Psychology of Love, Traditional Values, and Spiritual Growth
“You were born to win, but to be a winner you must plan to win, prepare to win, and expect to win.”

“Even if I knew that tomorrow the world would go to pieces, I would still plant my apple tree.”
Earliest record is in a circular letter from Hessian Church minister Karl Lotz on 5 October 1944 and modified from a quote by Johanan ben Zakai according to [Landes, Richard Allen, Heaven on Earth: The varieties of the millennial experience, USA, Oxford University Press, 2011, 978-0-19-975359-8, https://books.google.com/books?id=seS-0JTykgoC&pg=PA48, 48]
Ref: en.wikiquote.org - Martin Luther / Disputed
Misattributed

“A man who dares to waste one hour of time has not discovered the value of life.”
volume I, chapter VI: "The Voyage", page 266 http://darwin-online.org.uk/content/frameset?pageseq=284&itemID=F1452.1&viewtype=image; letter to sister Susan Elizabeth Darwin (4 August 1836)
The Life and Letters of Charles Darwin (1887)
Source: The Life & Letters of Charles Darwin

“Life's tragedy is that we get old too soon and wise too late. ”

“Every saint has a past, and every sinner has a future.”

“Knowing is not enough, we must apply. Willing is not enough, we must do.”

“Most people are real nice, when you finally see them.”
Pt. 2, ch. 31
Jean Louise (Scout) Finch & Atticus Finch
Source: To Kill a Mockingbird (1962)
Context: "An' they chased him 'n' never could catch him 'cause they didn't know what he looked like, an' Atticus, when they finally saw him, why he hadn't done any of those things... Atticus, he was real nice..."
"Most people are, Scout, when you finally see them."

Source: Kabir, Hajara Muhammad (2010). Northern women development. [Nigeria]. ISBN 978-978-906-469-4. OCLC 890820657 note: 1940s, Male and Female (1949)

“Whatever the mind of man can conceive and believe, it can achieve.”
Actually said by Napoleon Hill, Stone later added the line "...with P.M.A." (Positive Mental Attitude) to the end of this quote.
Misattributed
Variant: Whatever the mind of man can conceive and believe, it can achieve.

“Dream beautiful dreams and then work to make those dreams come true.”

“People who know little are usually great talkers, while men who know much say little.”

“That man is richest whose pleasures are the cheapest.”
March 11, 1856
Journals (1838-1859)

“The power of imagination makes us infinite.”
1 September 1875, page 226
John of the Mountains, 1938
Context: How infinitely superior to our physical senses are those of the mind! The spiritual eye sees not only rivers of water but of air. It sees the crystals of the rock in rapid sympathetic motion, giving enthusiastic obedience to the sun's rays, then sinking back to rest in the night. The whole world is in motion to the center. So also sounds. We hear only woodpeckers and squirrels and the rush of turbulent streams. But imagination gives us the sweet music of tiniest insect wings, enables us to hear, all round the world, the vibration of every needle, the waving of every bole and branch, the sound of stars in circulation like particles in the blood. The Sierra canyons are full of avalanche debris — we hear them boom again, for we read past sounds from present conditions. Again we hear the earthquake rock-falls. Imagination is usually regarded as a synonym for the unreal. Yet is true imagination healthful and real, no more likely to mislead than the coarser senses. Indeed, the power of imagination makes us infinite.

“Good friends, good books, and a sleepy conscience: this is the ideal life.”

Correspondence, Letters to Mademoiselle Leroyer de Chantepie
Variant: Do not read as children do to enjoy themselves, or, as the ambitious do to educate themselves. No, read to live.
Context: Do not read as children do to enjoy themselves, or, as the ambitious do to educate themselves. No, read to live. (June 1857)

Source: The All-Girl Filling Station's Last Reunion

“As long as there's life, there's hope.”

“Always remember that you are absolutely unique. Just like everyone else.”
Variant: Always remember that you are absolutely unique. Just like everyone else.

“Some people look for a beautiful place, others make a place beautiful.”

“A room without books is like a body without a soul.”
Attributed to Cicero in J. M. Braude's Speaker's Desk Book of Quips, Quotes, & Anecdotes (Jaico Pub. House, 1966), p. 52.
Dennis McHenry in a 2011 post at theCAMPVS.com http://thecampvs.com/2011/08/03/cicero-on-books-and-the-soul/ identified a source for the exact form of words in the essay "On the Pleasure of Reading" http://books.google.com/books?id=0YfQAAAAMAAJ&dq=cicero%20%22room%20without%20books%22%20%2B%22contemporary%20review%22&pg=PA240#v=onepage&q&f=false by Sir John Lubbock, published in The Contemporary Review, vol. 49 (1886) https://archive.org/details/contemporaryrev55unkngoog, pp. 240–51 https://archive.org/stream/contemporaryrev55unkngoog#page/n250/mode/2up, in which Lubbock wrote that "Cicero described a room without books as a body without a soul" (p. 241). The same sentence may also be found on p. 61 https://archive.org/stream/thepleasuresofli01lubbuoft#page/60/mode/2up of Lubbock's collection The Pleasures of Life. Part I. 18th edition (London and New York : Macmillan and Co. 1890) https://archive.org/details/thepleasuresofli01lubbuoft, in a lecture titled "A Song of Books". McHenry suggested that Lubbock may have had in mind the words "postea vero quam Tyrannio mihi libros disposuit mens addita videtur meis aedibus" at Cicero, Ad Atticum 4.8, which are translated by E. O. Winstedt on p. 293 https://archive.org/stream/letterstoatticus01ciceuoft#page/292/mode/2up of Cicero: Letters to Atticus I (London : William Heinemann, and New York : G. P. Putnam's Sons 1912) https://archive.org/details/letterstoatticus01ciceuoft "Since Tyrannio has arranged my books, the house seems to have acquired a soul", and by Evelyn Shuckburgh on p. 234 https://archive.org/stream/cu31924012541433#page/n283/mode/2up of The Letters of Cicero. Vol. I. B. C. 68–52 (London : George Bell and Sons 1908) https://archive.org/details/cu31924012541433 "Moreover, since Tyrannio has arranged my books for me, my house seems to have had a soul added to it" (although the Latin word " mens http://athirdway.com/glossa/?s=mens", rendered "soul" by both Winstedt and Shuckburgh, is more usually translated by the English "mind"). D. R. Shackleton Bailey in Cicero's Letters to Atticus (Harmondsworth : Penguin Books 1978), p. 162, translated "And now that Tyrannio has put my books straight, my house seems to have woken to life".
Disputed
Variant: Ut conclave sine libris ita corpus sine anima" A room without books is like a body without a soul

“No one can make you feel inferior without your consent.”
Disputed
Variant: No one can make you feel inferior without your permission.
Source: Sometimes claimed to appear in her book This is My Story, but in The Quote Verifier by Ralph Keyes (2006), Keyes writes on p. 97 that "Bartlett's and other sources say her famous quotation can be found in This is My Story, Roosevelt's 1937 autobiography. It can't. Quotographer Rosalie Maggio scoured that book and many others by and about Roosevelt in search of this line, without success. In their own extensive searching, archivists at the Franklin D. Roosevelt Library in Hyde Park, New York, have not been able to find the quotation in This Is My Story or any other writing by the First Lady. A discussion of some of the earliest known attributions of this quote to Roosevelt, which may be a paraphrase from an interview, can be found in this entry from Quote Investigator http://quoteinvestigator.com/2011/03/30/not-inferior/.

“Sometimes the questions are complicated and the answers are simple.”
Variant: Sometimes the questions are complicated and the answers are simple.

“Most people do not listen with the intent to understand; they listen with the intent to reply.”
Source: The Seven Habits Of Highly Effective People (1989), p. 239
Source: The 7 Habits of Highly Effective People: Powerful Lessons in Personal Change

“Never give up, for that is just the place and time that the tide will turn.”

“I attribute my success to this — I never gave or took any excuse.”
As quoted in The Gigantic Book of Teachers' Wisdom (2007) by Frank McCourt and Erin Gruwell, p. 410

“It's not the load that breaks you down, it's the way you carry it.”

“Live your beliefs and you can turn the world around.”

“It takes 20 years to build a reputation and five minutes to ruin it.”
Context: It takes 20 years to build a reputation and five minutes to ruin it. If you think about that, you'll do things differently.

“Happiness is nothing more than good health and a bad memory.”
Variant: Happiness is nothing more than good health and a bad memory.

“You'll never do a whole lot unless you're brave enough to try.”

“Wisely and slow; they stumble that run fast.”
Variant: Go wisely and slowly. Those who rush stumble and fall.
Source: Romeo and Juliet

“The future belongs to those who believe in the beauty of their dreams.”
Often attributed to Eleanor Roosevelt without an original source in her writings, for example in the introduction to It Seems to Me : Selected Letters of Eleanor Roosevelt (2001) by Leonard C. Schlup and Donald W. Whisenhunt, p. 2 http://books.google.com/books?id=UeFWjTMcLZYC&lpg=PP1&pg=PA2#v=onepage&q&f=false. But archivists have not been able to find the quote in any of her writings, see the comment from Ralph Keyes in The Quote Verifier above.
Disputed

“You never really learn much from hearing yourself speak.”

“To do nothing is the way to be nothing.”

“We must be free not because we claim freedom, but because we practice it.”
Source: Essays, Speeches & Public Letters

“I am not a product of my circumstances. I am a product of my decisions.”

Variant: People see the past better than it was, the present worse than it is and the future less resolved than it’ll be.

“The public is wonderfully tolerant. It forgives everything except genius.”
Source: The Artist as Critic: Critical Writings of Oscar Wilde

Jackson, Jim, Walking Together Forever: The Broad Street Bullies, Then and Now