“Adults are only obsolete children.”

“Every once in a while, I get mad. 'The Lorax' came out of my being angry. The ecology books I'd read were dull... In 'The Lorax,' I was out to attack what I think are evil things and let the chips fall where they might.”

“Once-ler! You're making such smogulous smoke - my poor swomee swans, why they can't sing a note! No one can sing who has smog in his throat.”

“You ought to be thankful a hole heaping lot, for The places and people you're lucky you're not!”

“Plant a new Truffula. Treat it with care. Give it clean water. And feed it fresh air.”

“Cease to lament for that thou canst not help; and study help for that which thou lamentest.”

“All difficulties are easy when they are known.”

“Diseases desperate grown By desperate appliances are relieved, Or not at all.”