Trees meant many things for Sartre: Being, mystery, the physical world, contingency. They were also a handy focus for phenomenological description. In his autobiography he also quotes something his grandmother once said to him: ‘It’s not just a question of having eyes, you have learn how to use them. Do you know what Flaubert did to the young Maupassant? He sat him down in front of a tree and gave him two hours to describe it.’ This is correct: Flaubert apparently did advise Maupassant to consider things ‘long and attentively’, saying:
There is a part of everything that remains unexplored, for we have fallen into the habit of remembering, whenever we use our eyes, what people before us have thought of the thing we are looking at. Even the slightest thing contains a little that is unknown. We must find it. To describe a blazing fire or a tree in a plain, we must remain before that fire or that tree until they no longer resemble for us any other tree or any other fire.
Quoted in At the Existentialist Café by Sarah Bakewell (p. 103)