Romantic quotes

'Where Do We Go From Here?" as published in Where Do We Go from Here : Chaos or Community? (1967), p. 62; many statements in this book, or slight variants of them, were also part of his address Where Do We Go From Here?" which has a section below. A common variant appearing at least as early as 1968 has "Returning violence for violence multiplies violence..." An early version of the speech as published in A Martin Luther King Treasury (1964), p. 173, has : "Returning hate for hate multiplies hate..."
1960s
Source: A Testament of Hope: The Essential Writings and Speeches
Context: The ultimate weakness of violence is that it is a descending spiral, begetting the very thing it seeks to destroy. Instead of diminishing evil, it multiplies it. Through violence you may murder the liar, but you cannot murder the lie, nor establish the truth. Through violence you may murder the hater, but you do not murder hate. In fact, violence merely increases hate. So it goes. … Returning hate for hate multiplies hate, adding deeper darkness to a night already devoid of stars. Darkness cannot drive out darkness: only light can do that. Hate cannot drive out hate: only love can do that.

Variant: Whatever our souls are made of, his and mine are the same
Source: Wuthering Heights

A line written by Ono many years before, and quoted by Lennon in December 1980, as quoted in All We Are Saying : The Last Major Interview with John Lennon and Yoko Ono (2000) by John Lennon, Yōko Ono, David Sheff, p. 16.
Source: Grapefruit: A Book of Instructions and Drawings

"In Search of a Majority: An Address" (Feb 1960); reprinted in Baldwin, "Nobody Knows My Name: More Notes of a Native Son" https://en.wikipedia.org/wiki/Nobody_Knows_My_Name (1961)

Variant: You know you're in love when you can't fall asleep because reality is finally better than your dreams.

Variant: I love you as one loves certain dark things, secretly, between the shadow and the soul.
Source: 100 Love Sonnets

Variant: Everyone wants to ride with you in the limo, but what you want is someone who will take the bus with you when the limo breaks down.

1979

Source: The Alchemist

The Prophet (1923)

Source: Clockwork Princess

Source: Going Bovine

Variant: It's one thing to fall in love. It's another to feel someone else fall in love with you, and to feel a responsibility toward that love.
Source: Every Day

Source: Lolita

Variant: Life is not the breaths you take but the moments that take your breath away.

Source: Eat, pray, love: one woman's search for everything

Frequently misattributed to Marilyn Monroe or Kurt Cobain.
Source: https://books.google.com/books?id=xUtdDnEhkMMC&pg=PT12&lpg=PT12#v=onepage&q&f=false
Source: Autumn Leaves, Philosophical eLibrary, 2012, (Feuillets d'automne, 1941, trans. Jeanine Parisier Plottel)

The Bell (1958), ch. 19; 2001, p. 219.

Variant: Sometimes good things fall apart so that better things can fall together.

II-II, q. 26, art. 6
Summa Theologica (1265–1274)

"A Dream Within a Dream" (1849).
Context: You are not wrong, who deem
That my days have been a dream;
Yet if hope has flown away
In a night, or in a day,
In a vision, or in none,
Is it therefore the less gone?
All that we see or seem
Is but a dream within a dream.

Manuscript Found in Accra (2012), Love has always passed me by

Variant: Kiss me and you will see how important I am.
Source: The Unabridged Journals of Sylvia Plath

frequently attributed to Lennon, but entirely unsourced
Disputed

Source: Northanger Abbey

Source: Second Glance

Jace to Clary, pg. 331
Variant: There is no pretending, I love you, and I will love you until I die, and if there is life after that, I'll love you then.
Source: The Mortal Instruments, City of Glass (2009)

Source: War and Peace

Source: When You Come to a Fork in the Road, Take It!: Inspiration and Wisdom from One of Baseball's Greatest Heroes

Variant: You want my opinion? We're all a little weird. And life is a little weird. And when we find someone whose weirdness is compatible with ours, we join up with them and fall into mutually satisfying weirdness — and call it love — true love.
Source: True Love (1998)

Source: Me: Stories of My Life

Without Love
Music, Slippery When Wet (1986)

Source: Wasted: A Memoir of Anorexia and Bulimia

Source: The Notebook

Variant: Doubt thou the stars are fire
Doubt thou the sun doth move
Doubt truth to be a liar
But never doubt I love
Source: Hamlet

Source: Lord Arthur Savile's Crime and Other Stories

Source: The Wise Man's Fear (2011)
Context: We love what we love. Reason does not enter into it. In many ways, unwise love is the truest love. Anyone can love a thing because. That's as easy as putting a penny in your pocket. But to love something despite. To know the flaws and love them too. That is rare and pure and perfect.

Gwendolen, Act III.
The Importance of Being Earnest (1895)
Variant: If you are not too long, I will wait here for you all my life.

Variant: I love her, and that's the beginning and end of everything.
Source: Dear Scott, Dearest Zelda: The Love Letters of F. Scott and Zelda Fitzgerald

Source: Romeo and Juliet

"Jubal Harshaw" in the first edition (1961); the later 1991 "Uncut" edition didn't have this line, because it was one Heinlein had added when he went through and trimmed the originally submitted manuscript on which the "Uncut" edition is based. Heinlein also later used a variant of this in The Cat Who Walks Through Walls where he has Xia quote Harshaw: "Dr. Harshaw says that 'the word "love" designates a subjective condition in which the welfare and happiness of another person are essential to one's own happiness.'"
Source: Stranger in a Strange Land (1961; 1991)

Source: No Exit

Source: 100 Love Sonnets

"Hyla Brook" (1920)
1920s

The Fall (1956)

"Nature Boy" (1948)
The greatest thing you'll ever learn is to love and be loved, just to love and be loved.
His assertion to Joe Romersa, of how his lyrics should be corrected, saying that "To be loved in return, is too much of a deal, and that has nothing to do with love."
Context: While we spoke of many things
Fools and kings
This he said to me:
"The greatest thing you'll ever learn
Is just to love and be loved in return."

Source: The Brothers Karamazov (Bratři Karamazovi)

Orsino, Act I, scene i.
Variant: Music, moody food
Of us that trade in love.
Source: Twelfth Night (1601)

Variant: You never lose by loving. You always lose by holding back.
Source: Chicken Soup for the Couple's Soul

Variant: Love involves a peculiar unfathomable combination of understanding and misunderstanding.

Source: Frostbite

Attributed to Irving as early as 1883. [Hit and miss : a story of real life, Angie Stewart, Manly, Chicago, J.L. Regan, 1883, i, http://hdl.handle.net/2027/osu.32435018229575?urlappend=%3Bseq=7] However, it does not seem to appear in Irving's known works. Other citations from the same year leave the quotation unattributed. [Henry S. (ed.), Clubb, The Peacemaker and Court of Arbitration, Volume 1, Universal Peace Union, 1883, 125, Philadelphia, https://books.google.com/books?id=Uu84AQAAMAAJ&pg=PA125] [The Australian Women's Magazine and Domestic Journal, Vol. 2 No. 2 (May 1883), 1883, Melbourne, 435, https://books.google.com/books?id=mq0sAQAAMAAJ&pg=PA435]. A similar passage is found in a pseudonymous novel published two years earlier in 1881: "Julia knew that sacrifices to patience are not in vain. Although they often do not produce the happiness for which they are made, they will, always, flow back and soften and purify the heart of the one who makes them". [Illma, Or, Which was Wife?, Miss, M.L.A., Cornwell & Johnson, 1881, 239, New York, http://hdl.handle.net/2027/osu.32435017658592?urlappend=%3Bseq=245]
Disputed

Variant: Come to finish me off, Sweetheart?
Source: The Hunger Games

Variant: nobody hαs ever meαsured, not even poets, how much the heαrt cαn hold.

Source: Twelfth Night

Source: What is Surrealism?: Selected Writings

Source: Jazz

Variant: Then she kissed him. Her kiss was a question he wanted to spend his whole life answering.
Source: The History of Love (2005), P. 11

Source: The Notebook

Source: The Princess Bride