Looking at it as analytically as possible, something that is very hard to analyse, I came up with six criteria. And what... if you could say what is a perfect cut, which is dangerous territory, it would look at each of the criteria and say: yes, it did that, and yes it did that, and it did that, and it did that. And those six criteria were at the top the most difficult to quantify, which is that, that transition from one shot to the next made you feel a certain way, it had an emotion with it, there was an emotional value to it, and that emotion was the correct one for that place in the film.

The next one, one step down in the ladder was: story. Did that cut help you to understand the story, why... what was being done and why was it being done? So this in a way gets back to our... the three levels of the brain, because the third one is rhythm: did it happen at the right place rhythmically. And basically, the music of the cut. If you think of editing as visual music, did that new shot come in at the right moment in the same way that the clarinet comes in at the right, exactly the right moment in that clarinet concerto, not a millisecond before or after, but right there. And, so these three levels of emotion and story, which is to say logic, and rhythm, which is a kind of instinctual thing, echo these three different layers of the brain.

The fourth level was: where is the eye of the audience likely to be looking? And if you divide the frame up into as simple as possible, quadrants, upper left, upper right, lower left, lower right, and then maybe the centre. So five things. Are they looking there or there or there or there? Because as a general rule, at the moment you cut, it's good to take into account, what is there in the new shot because that's where their eye will land. I'm looking there which is the point of the gun. At the moment of the cut, what do I see there? Sometimes you want something definitely to be there, other times you want it just to be blank so that the eye then looks for what the other focus of interest was. It all depends, but you have to take into consideration what, where the focus of the eye is because people are not looking at the whole frame, they are choosing to look in various areas, particularly in cinema as opposed to television. Historically, television people were further from the screen and the screen was smaller. In cinema, the screen was bigger and you're kind of looking around; it's more of a mural. Anyway, take into consideration where's the audience looking and how is their focus of attention carried across the moment of the cut.

The fifth thing was questions of the transposition of three dimensions into two. This is the so-called 180 degree rule, which is: are people, are we convinced that person A is looking at person B, and vice versa if they're having a conversation? And if you're cutting from one angle to another, the eye line of these two people having a conversation that is edited needs to intersect in a way that convinces us that they are in fact looking at each other even though they may have been two shots shot three months apart, and that the other actor wasn't actually there at the time of shooting, but it works, it's part of the chemistry of film montage that it works. So, does the cut take this into consideration the two-dimensional reality of the screen?

And then, the last one is the three-dimensional reality of the physical space that's being talked about. So, if the person gets out of the car to go into the house do they open the door to the car and walk up the path, open the door, and go into the house? If you did that, then the continuity of that space is maintained, and back in the early days of film, 1910, 1920, 1930, this was, people tried to follow this rule, because they were afraid that if they didn't follow the rule the audience would become upset, or confused: wait a minute, how did he get there, we didn't see him do that.

So, these are six things that you try to make an effort, and in shooting the film, the crew shooting the film, also it has to have these things in mind when they're doing it. Exactly how it's going to work out, nobody is 100% sure, but you are thinking about these things at the time of shooting.