„Happiness is an imaginary condition, formerly attributed by the living to the dead, now usually attributed by adults to children, and by children to adults.“

„The value of marriage is not that adults produce children, but that children produce adults.“

—  Peter de Vries American editor and novelist 1910 - 1993

„Is adult entertainment killing our children? Or is killing our children entertaining adults?“

—  Marilyn Manson American rock musician and actor 1969

As quoted in MarilynManson.com (2000).
2000s

„Children in school are not students, they are pupils. It is typical of certain kinds of politicians that they should regard children as adults, the better subsequently, and consequently, to regard adults as children.“

—  Theodore Dalrymple English doctor and writer 1949

Mr Brown's self-esteem issue - or, asks Theodore Dalrymple, does Gordon Brown really believe that he can solve the problems of the world? http://www.socialaffairsunit.org.uk/blog/archives/001326.php (January 24, 2007).
The Social Affairs Unit (2006 - 2008)

„The difference between children and adults is that they're shorter - not dumber.“

—  Mo Willems American children's illustrator and writer 1968

„Adults should strive to be more like children.“

—  Lorin Morgan-Richards American poet, cartoonist, and children's writer 1975

Speaking at Women's march in Los Angeles (21 January 2017).

„But some children have clearer vision than adults.“

—  Edmund Cooper British writer 1926 - 1982

Prisonner of Fire (1974)

„In their sympathies, children feel nearer animals than adults.“

—  Jessamyn West American author 1902 - 1984

The Life I Really Lived, part 1 (1979)
Contexto: In their sympathies, children feel nearer animals than adults. They frolic with animals, caress them, share with them feelings neither has words for. Have they ever stroked any adult with the love they bestow on a cat? Hugged any grownup with the ecstasy they feel when clasping a puppy?

„Children are the vessels into which adults pour their poison.“

—  Salman Rushdie, livro Midnight's Children

Fonte: Midnight's Children (1981)

„Adults are just obsolete children and the hell with them.“

—  Dr. Seuss American children's writer and illustrator, co-founder of Beginner Books 1904 - 1991

On writing for adults, as quoted in Of Sneetches and Whos and the Good Dr. Seuss: Essays on the Writings and Life of Theodor Geisel (1997) by Thomas Fensch, p. 96

„I've found what makes children happy doesn't always prepare them to be courageous, engaged adults.“

—  Brené Brown US writer and professor 1965

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

„Women will risk their lives to protect children, but rarely risk their lives to protect an adult man.“

—  Warren Farrell, livro The Myth of Male Power

Fonte: The Myth of Male Power (1993), Part II: The Glass Cellars of the disposable sex, p. 230.

„It can be said that deeply traumatized children grow into adults who live in the minefield of their own extreme emotions. Plus ca change.“

—  Antonella Gambotto-Burke, livro The Pure Weight of the Heart

Fonte: The Pure Weight of the Heart (1998), P. 326.

„For children love is a feeling; for adults, it is a decision. Children wait to learn if their love is true by seeing how long it lasts; adults make their love true by never wavering from their commitment.“

—  Orson Scott Card, livro Pathfinder

Fonte: Pathfinder

„Adults must remember that they look like insane giants to children.“

—  Irving Fiske American writer 1908 - 1990

Attributed without citation in Isabella Fiske McFarlin, et al., "Free The Kids! and Quarry Hill Community" http://search.proquest.com/openview/e76b1d1a966283049dcf60bcb9386c4d/1, Journal of Psychohistory, Vol. 21 No. 1 (Summer 1993), p. 21

„Children are not less intelligent than adults; what they are is less informed.“

—  Philip Pullman English author 1946

„Animation is not just for children - it's also for adults who take drugs.“

—  Paul McCartney English singer-songwriter and composer 1942

„We're a nation of exhausted and over-stressed adults raising over-scheduled children.“

—  Brené Brown US writer and professor 1965

„Children like to work, and are always eager to imitate the work of adults.“

—  Georgi Plekhanov Russian revolutionary 1856 - 1918

Utopian Socialism in the Nineteenth Century, 1913, Ch. 5.

„It is not size or age or childishness that separates children from adults. It is "responsibility."“

—  Jules Feiffer American cartoonist, screenwriter and playwright 1929

The Great Comic Book Heroes http://books.google.com/books?id=zxbuAAAAMAAJ&q=%22It+is+not+size+or+age+or+childishness+that+separates+children+from+adults+It+is+responsibility%22&pg=PA75#v=onepage (1965)