For me, trees have always been the most penetrating preachers. I revere them when they live in tribes and families, in forests and groves. And even more I revere them when they stand alone. They are like lonely persons. Not like hermits who have stolen away out of some weakness, but like great, solitary men, like Beethoven and Nietzsche. In their highest boughs the world rustles, their roots rest in infinity; but they do not lose themselves there, they struggle with all the force of their lives for one thing only: to fulfil themselves according to their own laws, to build up their own form, to represent themselves. Nothing is holier, nothing is more exemplary than a beautiful, strong tree. When a tree is cut down and reveals its naked death-wound to the sun, one can read its whole history in the luminous, inscribed disk of its trunk: in the rings of its years, its scars, all the struggle, all the suffering, all the sickness, all the happiness and prosperity stand truly written, the narrow years and the luxurious years, the attacks withstood, the storms endured. And every young farmboy knows that the hardest and noblest wood has the narrowest rings, that high on the mountains and in continuing danger the most indestructible, the strongest, the ideal trees grow.

Trees are sanctuaries. Whoever knows how to speak to them, whoever knows how to listen to them, can learn the truth. They do not preach learning and precepts, they preach, undeterred by particulars, the ancient law of life.

A tree says: A kernel is hidden in me, a spark, a thought, I am life from eternal life. The attempt and the risk that the eternal mother took with me is unique, unique the form and veins of my skin, unique the smallest play of leaves in my branches and the smallest scar on my bark. I was made to form and reveal the eternal in my smallest special detail.

A tree says: My strength is trust. I know nothing about my fathers, I know nothing about the thousand children that every year spring out of me. I live out the secret of my seed to the very end, and I care for nothing else. I trust that God is in me. I trust that my labor is holy. Out of this trust I live.

When we are stricken and cannot bear our lives any longer, then a tree has something to say to us: Be still! Be still! Look at me! Life is not easy, life is not difficult. Those are childish thoughts. Let God speak within you, and your thoughts will grow silent. You are anxious because your path leads away from mother and home. But every step and every day lead you back again to the mother. Home is neither here nor there. Home is within you, or home is nowhere at all.

A longing to wander tears my heart when I hear trees rustling in the wind at evening. If one listens to them silently for a long time, this longing reveals its kernel, its meaning. It is not so much a matter of escaping from one's suffering, though it may seem to be so. It is a longing for home, for a memory of the mother, for new metaphors for life. It leads home. Every path leads homeward, every step is birth, every step is death, every grave is mother.

So the tree rustles in the evening, when we stand uneasy before our own childish thoughts: Trees have long thoughts, long-breathing and restful, just as they have longer lives than ours. They are wiser than we are, as long as we do not listen to them. But when we have learned how to listen to trees, then the brevity and the quickness and the childlike hastiness of our thoughts achieve an incomparable joy. Whoever has learned how to listen to trees no longer wants to be a tree. He wants to be nothing except what he is. That is home. That is happiness.

- Hermann Hesse, Bäume. Betrachtungen und Gedichte

‘Of course, you have to wonder about where the wood came from.

Well, it came from a tree, and the substance of a tree is carbon. Where did that come from? It comes from the air, it’s carbon dioxide from the air. People look at trees and they think they come out of the ground but really trees come out of the air. The carbon dioxide in the air goes into the tree and it changes it; it kicks out the oxygen, pushing the oxygen away from the carbon and leaving the carbon substance with water. (The water comes out of the ground, but how did it get in there? It came out of the air, down from the sky. So in fact most of a tree is out of the air. There’s just a little bit from the ground, some minerals, and so forth.) Now as we know, oxygen and carbonstick very, very tight. How is it that the tree is so smart as to manage to take the carbon dioxide which is the carbon and oxygen so nicely combined, and undo it that easily?” ‘Ah!” you say “life has some mysterious force…” But no – the sun is shining, and it’s the sunlight that comes down and knocks this oxygen away from the carbon, and now the oxygen is some terrible by-product which the tree splits back into the air, leaving the carbon and the water and stuff to make the substance of the the tree.'

- Richard Feynman