Variant: It has been said, 'time heals all wounds.' I do not agree. The wounds remain. In time, the mind, protecting its sanity, covers them with scar tissue and the pain lessens. But it is never gone.
Quotes about tissue
A collection of quotes on the topic of tissue, other, life, time.
Quotes about tissue

“Scar tissue is stronger than regular tissue. Realize the strength, move on.”

Source: Kinski Uncut : The Autobiography of Klaus Kinski (1996), p. 72-73
Context: At a performance everything works out on its own. I've solved the mystery: You have to submit silently. Open up, let go. Let anything penetrate you, even the most painful things. Endure. Bear up. That's the magic key! The text comes by itself, and its meaning shakes the soul. Everything else is taken care of by the life one has to live without sparing oneself. You mustn't let scar tissue form on your wounds; you have to keep ripping them open in order to turn your insides into a marvelous instrument that is capable of anything. All this has its price. I become so sensitive that I can't live under normal conditions. That's why the hours between performances are worst.

Breakfast of Champions (1973)
Context: I thought Beatrice Keedsler had joined hands with other old-fashioned storytellers to make people believe that life had leading characters, minor characters, significant details, insignificant details, that it had lessons to be learned, tests to be passed, and a beginning, a middle, and an end.
As I approached my fiftieth birthday, I had become more and more enraged and mystified by the idiot decisions made by my countrymen. And then I had come suddenly to pity them, for I understood how innocent and natural it was for them to behave so abominably, and with such abominable results: They were doing their best to live like people invented in story books. This was the reason Americans shot each other so often: It was a convenient literary device for ending short stories and books.
Why were so many Americans treated by their government as though their lives were as disposable as paper facial tissues? Because that was the way authors customarily treated bit-part players in their madeup tales.
And so on.
Once I understood what was making America such a dangerous, unhappy nation of people who had nothing to do with real life, I resolved to shun storytelling. I would write about life. Every person would be exactly as important as any other. All facts would also be given equal weightiness. Nothing would be left out. Let others bring order to chaos. I would bring chaos to order, instead, which I think I have done.
If all writers would do that, then perhaps citizens not in the literary trades will understand that there is no order in the world around us, that we must adapt ourselves to the requirements of chaos instead.
It is hard to adapt to chaos, but it can be done. I am living proof of that: It can be done.
“The lessons of life amount not to wisdom, but to scar tissue and callus.”
Variant: Most things break, including hearts. The lessons of life amount not to
wisdom, but to scar tissue and callus.
Source: The Spectator Bird
A Voice Crying in the Wilderness (Vox Clamantis in Deserto) (1990)

Source: Hopes and Impediments: Selected Essays
Source: The Bloody Chamber and Other Stories

Source: This Is How: Proven Aid in Overcoming Shyness, Molestation, Fatness, Spinsterhood, Grief, Disease, Lushery, Decrepitude & More. For Young and Old Alike.

“He seemed to be made of sunshine and blood-red tissue and clear weather.”
Source: Selected Stories
Triumph of the Root-Heads, p. 367
Leonardo's Mountain of Clams and the Diet of Worms (1998)
Chick tracts, " Who Murdered Clarice? http://www.chick.com/reading/tracts/1009/1009_01.asp" (2000)

“Montaigne,” p. 7
Reperusals and Recollections (1936)

On her depression and suicide attempt, p. 158.
Autobiography

Marlow: Clintons’ ‘Serial Dishonesty’ The ‘Danger of Putting Them Back In The White House’ http://www.breitbart.com/video/2016/03/07/httpswww-youtube-comwatchvtqcycm6uihs/ (March 7, 2016)
“Civilization is a scar tissue from a past of violence and destruction.”
Source: Social Amnesia: A Critique of Conformist Psychology from Adler to Laing (1975), p. 31

Quote was introduced with the phrase:
In the lecture on the weaver's art, we are reminded of the superiority of Indian muslins and Chinese and Persian carpets, and the gorgeous costumes of the middle ages are contrasted with our own dark ungraceful garments. The Cufic inscriptions that have so perplexed antiquaries, were introduced with the rich Eastern stuffs so much sought after by the wealthy class, and though, as Mr. Burges observes
Source: Art applied to industry: a series of lectures, 1865, p. 85; Cited in: " Belles Lettres http://books.google.com/books?id=0EegAAAAMAAJ&pg=PA143" in: The Westminster Review, Vol. 84-85. Baldwin, Cradock, and Joy, 1865. p. 143
"Brotherhood by Inversion", p. 327
Leonardo's Mountain of Clams and the Diet of Worms (1998)
Anatol Rapoport (1956) "The Search for Simplicity"
1950s

Source: Vamps and Tramps (1994), "No Law in the Arena: A Pagan Theory of Sexuality", p. 32

Source: The Limits of Evolution, and Other Essays, Illustrating the Metaphysical Theory of Personal Ideaalism (1905), Human Immortality: its Positive Argument, p.295

“A Treatise on Mannequins” http://www.schulzian.net/translation/shops/treatise1.htm
His father, Creativity

Quote in Marc Chagall - the Russian years 1906 – 1922, editor Christoph Vitali, exhibition catalogue, Schirn Kunsthalle Frankfurt, 1991, pp. 24-25
1920's, My life (1922)
Grassé, Pierre Paul (1977); Evolution of living organisms: evidence for a new theory of transformation. Academic Press, p. 2
Evolution of living organisms: evidence for a new theory of transformation (1977)
Original: La finalité immanente est une propriété intrinseque des etres vivants, sans elle, ils n'existeraient pas. Considérés en tant qu' unités fonctionelles autonomes, leurs constituants: organes, tissus, cellule isolée, au meme titre que les autres propriétés: nutrition, défense de l'organisme, croissance, reproduction, sont subordonnés à une fin. Quand il s'agit de ces propriétes, les biologistes ne se disputent pas; mais si l'on pronounce le mot finalité, c'est un levée de boucliers. Probablement parce qu'ils ne distinguent pas la finalité de fait ou immanente, de la finalité trascendante. Sur cette derniere, le biologiste n'a que peu, sinon rien à dire; elle ressortit de la métaphysique

Brown : The Last Discovery of America (2003)

The Art of Fiction http://public.wsu.edu/~campbelld/amlit/artfiction.html (1884)

Sanctuary http://www.wsu.edu/~campbelld/wharton/books/snctr10.txt, (1903) part II, ch. IV

Dig a Hole
Kingdom Come (2006)

I.8 Material Structure. in Nature, p. 26
1921 - 1930, Pedagogical Sketch Book, (1925)
Oh No, I've Got A Cold

Letter to F. Scott Fitzgerald (1 July 1925); published in Ernest Hemingway: Selected Letters 1917–1961 (1981) edited by Carlos Baker
What the Butler Saw (1969), Act II

"Ricky Williams on fasting, energy, religion" by Tim Graham, ESPN.com (17 September 2010) http://www.espn.com/blog/afceast/post/_/id/18355/ricky-williams-on-fasting-and-religion.

Two Years Later: Mexico City Return
Queer: A Novel (1985)

Corot explains his making of the painting to his biographer Alfred Robaut, c. 1869; as quoted in Corot, Gary Tinterow, Michael Pantazzi, Vincent Pomarède - Galeries nationales du Grand Palais (France), National Gallery of Canada, Metropolitan Museum of Art (New York, N.Y.), 1996, p. 277
about his painting 'Landscape with Figures', also called 'La Toilette', Corot painted in 1859
1860s

From the second book, "The Book of the Innocent"
The Pillow Book

The Autocrat of the Breakfast Table (1858)
"The Crooked Wood", p. 208
The Journey Home (1977)

Politico TV, May 2007 http://www.youtube.com/watch?v=dojI3UYIcGg
2000s, 2006-2009

“The honors Hollywood has for the writer are as dubious as tissue-paper cuff links.”
Books
Source: Rite of Passage (1968), Chapter 18 (p. 222).

Source: Permaculture: A Designers' Manual (1988), chapter 2.5

Lean Logic, (2016), p. 123, entry on Economics http://www.flemingpolicycentre.org.uk/lean-logic-surviving-the-future/

18 January 1870, pages 43-44
John of the Mountains, 1938
Incognito: The Secret Lives of The Brain
Source: Last and First Men (1930), Chapter XIV: Neptune; Section 3, “Slow Conquest” (p. 211)
"Antaeus in Manhattan"
The Lives of a Cell: Notes of a Biology Watcher (1974)

The Education of Henry Adams (1907)
The Never-Ending Wrong (1977)

“My back is so scar-tissued that you couldn't find a place to slip a knife.”
Source: A Dictionary of New Zealand Political Quotations (2000), p. 96.

[The Way Things Ought to Be, Pocket Books, October 1992, 193, 978-0671751456, 92028659, 26397008, 1724938M]

River out of Eden (1995)
Source: Star Maker (1937), Chapter IX: The Community of Worlds; 3. A Crisis in Galactic History (p. 117)

Braitenberg (1948), quoted in: Elke Maier (2012) " Spying on God http://www.mpg.de/6348834/S005_Flashback_086-087.pdf" in Max Planck Research, March 2012
Description of Braitenberg's first experience observing brain tissue under a microscope as medical student in Rome.

Dirk Gently's Holistic Detective Agency (1987)
Context: If the Universe came to an end every time there was some uncertainty about what had happened in it, it would never have got beyond the first picosecond. And many of course don’t. It’s like a human body, you see. A few cuts and bruises here and there don’t hurt it. Not even major surgery if it’s done properly. Paradoxes are just the scar tissue. Time and space heal themselves up around them and people simply remember a version of events which makes as much sense as they require it to make.

Discussing the result of an experiment where about 1 out of 8000 alpha particles were scattered backwards when fired at a thin sheet of metal foil, which led to the discovery of the atomic nucleus, as quoted in Rutherford and the Nature of the Atom (1964) by E. N. da C. Andrade, p. 111, and in Nobel Laureates in chemistry, 1901-1992 http://books.google.com/books?id=jEy67gEvIuMC&lpg=PP1&pg=PA57#v=onepage&q&f=false by Laylin K. James, p. 57
Context: It was quite the most incredible event that has ever happened to me in my life. It was almost as incredible as if you fired a 15-inch shell at a piece of tissue paper and it came back and hit you.

Source: Morals and Dogma of the Ancient and Accepted Scottish Rite of Freemasonry (1871), Ch. XXII : Grand Master Architect, p. 191
Context: Life is no negative, or superficial or worldly existence. Our steps are evermore haunted with thoughts, far beyond their own range, which some have regarded as the reminiscences of a preesistent state. So it is with us all, in the beaten and worn track of this worldly pilgrimage. There is more here, than the world we live in. It is not all of life to live. An unseen and infinite presence is here; a sense of something greater than we possess; a seeking, through all the void wastes of life, for a good beyond it; a crying out of the heart for interpretation; a memory of the dead, touching continually some vibrating thread in this great tissue of mystery.

The Purpose of Life is Religious Discovery
Start your own Religion (1967)

Journal Intime (1882), Journal entries
Context: In the conduct of life, habits count for more than maxims, because habit is a living maxim, becomes flesh and instinct. To reform one's maxims is nothing: it is but to change the title of the book. To learn new habits is everything, for it is to reach the substance of life. Life is but a tissue of habits.

Source: Caliban's War (2012), Chapter 51 (p. 563)

Yevgeni Chazov, spoken in a special session of the Central Committee one day after Chernenko died.

Original: (fr) La souffrance forme le tissu de l'existence, elle est le lieu où la vie devient vivante, la réalité et l'effectivité phénoménologique de ce devenir.
Source: Michel Henry, L'Essence de la manifestation, 1963, t. 2, § 70, p. 828
Source: Books on Phenomenology of Life, The Essence of Manifestation (1963)

The Aquarian Conspiracy (1980), Chapter Three, Brains Changing, Minds Changing
The Dark Sea of Scandal https://www.dioceseofbaker.org/documents/2019/2/100718.pdf (October 7, 2018)