There's a curious thing about red that I was reading the other day, which is that the colour red is created by the human mind, in the sense that we are what's called 'trichromatic animals'. We have three different kinds of rods in our eye. We have a blue rod, or a nerve ending that responds to the wavelength of blue light. And we have a green rod that responds to green light. And we have what's known as a yellow-green, let's just call it 'the yellow'. We don't have a red cone, and so how do we see red? We see red when the brain received nothing from the blue cone, so the blue cones are not seeing anything in that area, which is a red area. So the blue says 'nope', green says 'nope', and yellow-green says, 'I detect a tiny something which is leaving.' It's kind of on the north flank of the yellow-green cone. And yet, we see red. We invent a quality which we call red, which is technically the absence of blue, the absence of green, and a diminishing amount of yellow light.

And I... It meshes, for me, this idea with certain other ideas, because red is generally the most vibrant colour. We use it for stoplights, we use it on the camera to say it's on. Whenever we have to make sure: do you see this colour? We use red. And if you ask people point blank, to very quickly name a colour, red comes out. And yet, red is... We're not passively responding to red, we're creating red. And we're creating it in the sense that we create the impression we have of three dimensions, which doesn't really exist. Our brain is being fed by a flat image from the right eye and a flat image from the left eye, and because we don't like flatness and doubleness, we mesh this neurologically, somehow very complicated algorithm, into three dimensions. The chair is there and the table is behind the chair, and I feel that because of the three-dimensionality that I'm looking at. If I close one eye, I deduce that it's behind, but I don't feel it. And in the same sense, red doesn't really exist. It's a deduction. 'Oh, there is a light coming at me, and it's not blue, it's not green, but I'm not receiving a signal from a red cone.' Which is what, intuitively, that's what you would think. 'Oh, it's such a powerful signal that it must come from... 'There must be a red nerve ending. And when the red is stimulated, we see red. But that's not the case.

And in fact, I think you could generalise... I generalise it to say that the most vivid things that people see or hear are things that they don't really objectively see or hear, but things that they concoct out of other signals – that we produce three dimensions out of other signals. We produce out of red out of not red signals, but other things. And you know, it's generally a truism that the most powerful thing you can do to an audience in a film is not show them something, but make them think that they've seen it, to evoke their imagination. As soon as you actually show the thing, well, okay, there it is. But if you can imply it, you know, the whole lingerie industry is based on that. Which is, we're not going to show nakedness, because that is, you know, that has a limited shelf-life, so to speak. But lingerie, which hides the thing that you want to imagine, is an extremely powerful thing. So you know, if you wanted to reduce it, you know, filmmaking is kind of Victoria's Secret, but on a very high level. But I think it applies to all art and, you know, painting and theatre and dance. It's generally, we try to get an audience to a place, and it's difficult. But we try to get them to a place where they can imagine the thing that we do not show them. And because they have to imagine it, each person has to imagine it for themselves, it's a highly personal thing. What I imagine looking is something that this person looking at the same thing, may imagine something slightly different, or completely different.

Anyway, it's just curious to me that even in something as basic, but very complicated, as human sight and colour perception, you can kind of see a little evidence of the same principle at work.