Quotes about habit
A collection of quotes on the topic of habit, use, life, doing.
Quotes about habit

“If you quit ONCE it becomes a habit. Never quit!!!”

In his first school essay, while in Class VIII, expressing his ideas and ideals, in: p. 28.
Quest for Truth (1999)

Source: 1910s, My Larger Education, Being Chapters from My Experience (1911), Ch. V: The Intellectuals and the Boston Mob (pg. 118)

Letter to Catherine L. Moore (7 February 1937), in Selected Letters V, 1934-1937 edited by August Derleth and Donald Wandrei, pp. 407-408
Non-Fiction, Letters

“The world has a habit of going on.”

“We are what we repeatedly do. Excellence, therefore, is not an act, but a habit.”
Variant: We are what we repeatedly do. Greatness then, is not an act, but a habit
Source: The Story of Philosophy (1926), p. 87. The quoted phrases within the quotation are from the Nicomachean Ethics, Book II, 4; Book I, 7.
Context: Excellence is an art won by training and habituation: we do not act rightly because we have virtue or excellence, but we rather have these because we have acted rightly; 'these virtues are formed in man by his doing the actions'; we are what we repeatedly do. Excellence, then, is not an act but a habit: 'the good of man is a working of the soul in the way of excellence in a complete life... for as it is not one swallow or one fine day that makes a spring, so it is not one day or a short time that makes a man blessed and happy'.

Book 5, Chapter 33, Section 4. Translated by Philip Schaff et al. (full text at Wikisource).
Against Heresies

“It is difficult to exaggerate the power of habit.”
Guitar Craft Monograph III: Aphorisms, Oct. 27 1988

"The English People" (written Spring 1944, published 1947)<sup> http://alexpeak.com/twr/orwell/quotes/</sup>

"Lear, Tolstoy and the Fool," Polemic (March 1947)

“As to diseases, make a habit of two things — to help, or at least, to do no harm.”
Epidemics, Book I, Ch. 2, Full text online at Wikisource
Variant translation: The physician must be able to tell the antecedents, know the present, and foretell the future — must mediate these things, and have two special objects in view with regard to disease, namely, to do good or to do no harm.
Paraphrased variants:
Wherever a doctor cannot do good, he must be kept from doing harm.
Viking Book of Aphorisms : A Personal Selection (1988) by W. H. Auden and Louis Kronenberger, p. 213.

" Fake leather please! http://www.dnaindia.com/entertainment/report_fake-leather-please_1064075". Interview for Daily News and Analysis. November 14, 2006.

As quoted in Peter's Quotations : Ideas for Our Time (1979) by Laurence J. Peter, p. 299

1900s, The Strenuous Life: Essays and Addresses (1900), National Duties

"Sie wird das nothwendigste und härteste und die hauptsache in der Musique niemahlen bekommen, nämlich das tempo, weil sie sich vom jugend auf völlig befliessen hat, nicht auf den tact zu spiellen."
Letter to Leopold Mozart (24 October 1777), from Mozart: The Man and the Artist, as Revealed in his own Words by Friedrich Kerst, trans. Henry Edward Krehbiel (1906) http://www.gutenberg.org/dirs/etext03/wamma11.txt

“Habits and faculties are necessarily affected by the corresponding acts”
Golden Sayings of Epictetus
Context: If you have given way to anger, be sure that over and above the evil involved therein, you have strengthened the habit, and added fuel to the fire. If overcome by a temptation of the flesh, do not reckon it a single defeat, but that you have also strengthened your dissolute habits. Habits and faculties are necessarily affected by the corresponding acts... One who has had fever, even when it has left him, is not in the same condition of health as before, unless indeed his cure is complete. Something of the same sort is true also of diseases of the mind. Behind, there remains a legacy of traces and of blisters: and unless these are effectually erased, subsequent blows on the same spot will produce no longer mere blisters, but sores. If you do not wish to be prone to anger, do not feed the habit; give it nothing which may tend to its increase. At first, keep quiet and count the days when you were not angry: 'I used to be angry every day, then every other day: next every two, next every three days!' and if you succeed in passing thirty days, sacrifice to the Gods in thanksgiving. (75).

Gitanjali http://www.spiritualbee.com/gitanjali-poems-of-tagore/ (1912)
Context: Where the mind is without fear and the head is held high
Where knowledge is free
Where the world has not been broken up into fragments
By narrow domestic walls
Where words come out from the depth of truth
Where tireless striving stretches its arms towards perfection
Where the clear stream of reason has not lost its way
Into the dreary desert sand of dead habit
Where the mind is led forward by thee
Into ever-widening thought and action
Into that heaven of freedom, my Father, let my country awake.

The Discovery of India (1946)
Context: The world of today has achieved much, but for all its declared love for humanity, it has based itself far more on hatred and violence than on the virtues that make one human. War is the negation of truth and humanity. War may be unavoidable sometimes, but its progeny are terrible to contemplate. Not mere killing, for man must die, but the deliberate and persistent propagation of hatred and falsehood, which gradually become the normal habits of the people. It is dangerous and harmful to be guided in our life's course by hatreds and aversions, for they are wasteful of energy and limit and twist the mind and prevent it from perceiving truth.

"Notes on Nationalism" (1945)
Context: By "nationalism" I mean first of all the habit of assuming that human beings can be classified like insects and that whole blocks of millions or tens of millions of people can be confidently labelled "good" or "bad." But secondly — and this is much more important — I mean the habit of identifying oneself with a single nation or other unit, placing it beyond good and evil and recognizing no other duty than that of advancing its interests. Nationalism is not to be confused with patriotism. Both words are normally used in so vague a way that any definition is liable to be challenged, but one must draw a distinction between them, since two different and even opposing ideas are involved. By "patriotism" I mean devotion to a particular place and a particular way of life, which one believes to be the best in the world but has no wish to force on other people. Patriotism is of its nature defensive, both militarily and culturally. Nationalism, on the other hand, is inseparable from the desire for power. The abiding purpose of every nationalist is to secure more power and more prestige, not for himself but for the nation or other unit in which he has chosen to sink his own individuality.

“The chains of habit are generally too small to be felt until they are too strong to be broken.”

The Soul of Man Under Socialism (1891)
Context: Art is Individualism, and Individualism is a disturbing and disintegrating force. Therein lies its immense value. For what it seeks to disturb is monotony of type, slavery of custom, tyranny of habit, and the reduction of man to the level of a machine.

Variant: Habit is habit, and not to be flung out of the window by any man, but coaxed downstairs one step at a time.

“Love is an act of endless forgiveness, a tender look which becomes a habit.”
BBC obituary (2004)

“My worst habit is my fear & my destructive rationalizing.”
Source: The Unabridged Journals of Sylvia Plath

“Nothing is stronger than habit.”
Nil adsuetudine maius.
Variant translation: Nothing is more powerful than custom.
Book II, line 345
Ars Amatoria (The Art of Love)

“Nothing so needs reforming as other people's habits.”

“The spirit of the individual is determined by his dominating thought habits.”
Part 6 "Beyond System — The Ultimate Source of Jeet Kune Do"
Jeet Kune Do (1997)
Source: Bruce Lee Jeet Kune Do: Bruce Lee's Commentaries on the Martial Way

Saying published anonymously in The Dayspring, Vol. 10 (1881) by the Unitarian Sunday-School Society, and quoted in Life and Labor (1887) by Smiles; this is most often attributed to George Dana Boardman, at least as early as 1884, but also sometimes attributed to William Makepeace Thackeray as early as 1891, probably because in in Life and Labor Smiles adds a quote by Thackeray right after this one, to Charles Reade in 1903, and to William James as early as 1906, because it appears in his Principles of Psychology (1890).
Misattributed
Source: Happy Homes and the Hearts That Make Them

“For books continue each other, in spite of our habit of judging them separately.”
Source: A Room of One's Own and Three Guineas

“Rigid, the skeleton of habit alone upholds the human frame.”
Mrs Dalloway (1925)
Source: Mrs. Dalloway

Source: Speech to the Savage Club, 9 June 1899, in Mark Twain's Speeches (1910), ed. William Dean Howells, pp. 277–278 http://books.google.com/books?id=7etXZ5Q17ngC&pg=PA277. (Possibly fabricated from a paraphrase in Aaron Watson, The Savage Club: a Medley of History, Anecdote, and Reminiscence (1907), pp. 126–129 http://books.google.com/books?id=B1cuAAAAMAAJ&pg=PA63)

“Relearn astonishment, stop grasping for knowledge, lose the habit of the past.”
J. Agee, trans. (1989), p. 146
Das Geheimherz der Uhr [The Secret Heart of the Clock] (1987)

“We love our habits more than our income, often more than our life.”
Source: Sceptical Essays
“Motivation gets you going and habit gets you there.”

(1847)

Es gibt eine Menge kleiner Rücksichtslosigkeiten und Unarten, die an und für sich nichts bedeuten, aber furchtbar sind als Kennzeichen der Beschaffenheit der Seele.
Source: Aphorisms (1880/1893), p. 38.

For My Legionaries: The Iron Guard (1936), Nation and Culture

Source: 1910s, Mysticism and Logic and Other Essays http://archive.org/stream/mysticism00russuoft/mysticism00russuoft_djvu.txt (1918), Ch. 1: Mysticism and Logic

Metaphysical Elements of Ethics (1780). Translated by Thomas Kingsmill Abbott, translation available at Philosophy.eserver.org http://philosophy.eserver.org/kant/metaphys-elements-of-ethics.txt. From section "Preliminary Notions of the Susceptibility of the Mind for Notions of Duty Generally", Part C ("Of love to men")

Peace and Bread in Time of War (1922), Chapter 7 : Personal Reactions During War http://media.pfeiffer.edu/lridener/DSS/Addams/pb7.html

Quoted in "The Sniper at War: From the American Revolutionary War to the Present Day" - Page 67 - by Michael E. Haskew - History - 2005.

“Good habits are here more effectual than good laws elsewhere.”
…ibi boni mores valent quam alibi bonae leges. [http://www.fordham.edu/halsall/source/tacitus-germ-latin.html#19]
End of chapter 19, http://www.unrv.com/tacitus/tacitus-germania-5.php
Germania (98)

Preface to The Bertrand Russell Dictionary of Mind, Matter and Morals (1952) edited by Lester E. Denonn
1950s

“How use doth breed a habit in a man!”
Valentine, Act V, scene iv.
The Two Gentlemen of Verona (1590–1)

Source: Quest for Truth (1999), pp.32-33.

“There's no difference between the conquering of the unknown and the creation of habitable order.”
Source: https://www.youtube.com/watch?v=hdrLQ7DpiWs "Biblical Series II: Genesis 1: Chaos & Order"

The Notebooks of Leonardo da Vinci (1883), XIX Philosophical Maxims. Morals. Polemics and Speculations.

As quoted by Frank Edward Manuel, The Religion of Isaac Newton (1977)

Source: Elements of the Philosophy of the Human Mind, 1792, p. 334 (in 1829 edition https://books.google.nl/books?id=VxtSAAAAMAAJ)

“The most expensive habit in the world is celluloid, not heroin, and I need a fix every few years.”
Time, 1979

Letter to Harry O. Fischer (late February 1937), in Selected Letters V, 1934-1937 edited by August Derleth and Donald Wandrei, pp. 416-417
Non-Fiction, Letters

"The New York Times - The Opinion Pages", commentary about the November 2015 Paris attacks http://www.nytimes.com/2015/11/21/opinion/how-frances-leaders-failed-its-people.html?_r=0 (21 November 2015)

“Man is made of ordinary things, and habit is his nurse.”
Act I, sc. iv
Wallenstein (1798), Part II - Wallensteins Tod (The Death of Wallenstein)

Fundamenta fructificationis (1742). As quoted in John S. Wilkins (2009), "Species: A History of the Idea," University of California Press. p. 72

Sir Robert Peel
Biographical Studies (1907)

Of the Origin and Progress of Language (Edinburgh and London: J. Balfour and T. Cadell, 2nd ed., 1774), Vol. I, Book II, Ch. II, pp. 224-225 https://archive.org/stream/originandprogre01conggoog#page/n251/mode/2up.

Cesare to his father, Pope Alexander VI, (November, 1501), as quoted by Rafael Sabatini, 'The Life of Cesare Borgia', Chapter XI: The Letter to Silvio Savelli.

Letter to Steptoe Washington http://westillholdthesetruths.org/quotes/60/a-good-moral-character-is-the (5 December 1790)
1790s