After reading Michael Ondaajte's book on conversations with Walter Murch on the art of film editing, I've extracted some quotes from Walter Murch which have impressed me:
You sometimes get a situation in chemistry, where a solution is supersaturated: a vessel full of water and salt, and the salt is unable to crystallize. An unbalanced situation, where it's ready to react but not quite yet, because the vessel is so polished and perfect. But if you tap the vessel, you can shock the solution into crystallizing suddenly. I think film is one of those shocks, an invention that was unanticipated, in all its glory. And the shock of it caused certain things to crystallize within the supersaturated solution of nineteenth century culture.

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There are two approaches to reducing the length of a film: There's what I call the spaghetti-sauce method, which is simply to put the film on the stove with some heat under it, and stir. You taste it occasionally and say, That's great! Now the carrots are working with the tomatoes in a good wat, or, No, it's a little too thick, let's add some water! Gradually, organically, the volume of the film reduces to the appropriate level.

The opposite approach is more brutal. There was a brigand in Greek mythology, Procrustes, who lived on the road between Athens and Sparta. He had a cabin at a place where the road got very narrow, along the coast. Everyone who happened to pass his cabin was obliged to spend the night, and sleep on Procrustes' iron bed. While you were sleeping, he would either stretch you so that you were as long as the bed, or he would lop off things that stuck out, so that no matter how tall or short you were, by the time you left his cabin, you were the sam length as everyone else who'd been there.

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From my early editing experiences I became convinced that there was a connection between the patterns of a person's eye blinks and the patterns of their thoughts. That blinks are the equivalent of mental punctuation marks - commas, periods, semicolons, et cetera - separating and thus providing greater articulation to our thoughts... The upshot of all this is that I believe the pattern of cuts in a film, to be at its best, needs to reflect or acknowledge the pattern of thoughts of the characters in the film - which ultimately means the thought patterns of the audience.

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(On Walter Murch's father, a painter)
He said to me once, I don't paint the object, I paint the space between my eye and the object: that space contains the object the way the mould of an object contains the object. I am painting space and I am also constructing something on a two-dimensional piece of canvas that has its own dynamics, irrespective of the objects that are being painted.

And that's exactly the way I think about sound recording. If I go out to record a door-slam, I don't think I'm recording a door-slam. I think I am recording the space in which the door-slam happens.