“I should say that, in addition to my tree-love (it was originally called The Tree), it arose from my own pre-occupation with the Lord of the Rings, the knowledge that it would be finished in great detail or not at all, and the fear (near certainty) that it would be 'not at all'.”
About "Leaf by Niggle", in a letter to Caroline Everett (24 June 1957)
Context: I should say that, in addition to my tree-love (it was originally called The Tree), it arose from my own pre-occupation with the Lord of the Rings, the knowledge that it would be finished in great detail or not at all, and the fear (near certainty) that it would be 'not at all'. The war had arisen to darken all horizons. But no such analyses are a complete explanation even of a short story...
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John Ronald Reuel Tolkien 78
British philologist and author, creator of classic fantasy … 1892–1973Related quotes

My Periodic Table, New York <I>Times</I>, 24 July 2015

Elijah to Cyrano
The Other World (1657)
Context: The angel had told me in my dream that if I wanted to acquire the perfect knowledge I desired, I would have to go to the Moon. There I would find Adam's paradise and the Tree of Knowledge. As soon as I had tasted its fruit, my mind would be enlightened with all the truths a person could know. That is the voyage for which I built my chariot.
Finally, I climbed aboard and, when I was securely settled on the seat, I tossed the magnetic ball high into the air. The chariot I had built was more massive in the middle than at the ends; it was perfectly balanced because the middle rose faster than the extremities. When I had risen to the point that the magnet was drawing me to, I seized the magnetic ball and tossed it into the air again.

http://nofilmschool.com/2016/07/abbas-kiarostami-death-cinema-lessons

Disaster; reported in Bartlett's Familiar Quotations, 10th ed. (1919). Compare:
Oh, ever thus, from childhood’s hour,
I ’ve seen my fondest hopes decay;
I never loved a tree or flower
But ’t was the first to fade away.
- Thomas Moore, The Fire Worshippers, p. 26.

Source: The Good Body

“Even if I knew that tomorrow the world would go to pieces, I would still plant my apple tree.”
Earliest record is in a circular letter from Hessian Church minister Karl Lotz on 5 October 1944 and modified from a quote by Johanan ben Zakai according to [Landes, Richard Allen, Heaven on Earth: The varieties of the millennial experience, USA, Oxford University Press, 2011, 978-0-19-975359-8, https://books.google.com/books?id=seS-0JTykgoC&pg=PA48, 48]
Ref: en.wikiquote.org - Martin Luther / Disputed
Misattributed

“Even if I knew that tomorrow the world would go to pieces, I would still plant my apple tree.”
Martin Luther
Misattributed

"Methods of Work" (p. 64)
posthumous quotes, Degas: An Intimate Portrait' (1927)
epigraph, p. vi
A Sad Heart at the Supermarket: Essays & Fables (1962)