This may seem like an odd question, and you may think the answer is obvious: the spaces between the notes are part of the music too. But how often do we think about these spaces when we practise? And how often do we view them as an area of action, rather than as a break in activity?
Following the process: drawing what you see.
When I was younger, I attempted to improve my visual art skills. I remember looking at the African violet on the table in front of me, and trying to draw the flower. It was far harder than I thought. I thought I knew what the flower looked like. But when I really looked at the violet in front of me, the shapes didn’t conform to my mental image of what the flower ‘should’ look like. A combination of perspective and the background/environment around the flower changed the shapes. It left me with a dilemma: do I draw what I think is right, or draw what I actually see in front of me?
Betty Edwards in her book Drawing on the Right Side of the Brain speaks about this phenomenon. We struggle to draw what is in front of us, because we think we know what the object we are drawing ‘should’ look like. William Westney in his book The Perfect Wrong Note applies the same principle to music:
“musical notes are objects, and we know too much about them too – exactly where they should be and how they’re supposed to sound, for instance. Adopting the method Edwards suggests, an enlightened practicer would take a more open, inclusive view, and would set out to learn the specific physicality of the notes and the spaces between them. To put it another way, what we learn in the practice room should be 50 per cent notes and 50 per cent negative space.” 
Westney’s point is that the rests, pauses and the space between notes give shape not just to the notes, but to the way we approach them. Sometimes they are the place where we need to consider how we are going to play the next phrase; sometimes they are part of the phrase musically, but technically are full of incident and adjustment. In these cases just thinking of the notes – the product – is not going to be helpful at all. We need to think of all elements of playing as a whole, not just the end product.
So often we organise our practice sessions with the end product in mind. We have an idea of how we want the music to sound, and we concentrate upon that as we work on the piece. In this mode of practice, any thought that we give to mechanics or technique is secondary to the sound we want to create. It may even not be reasoned out with awareness and deliberation.
FM Alexander would call this ‘end-gaining’. He gives a fantastic definition of end-gaining in his chapter about a golfer who can’t keep his eye on the ball.
His habit is to work directly for his ends on the “trial and error” plan without giving due consideration to the means whereby those ends should be gained. In the present instance there can be no doubt that the particular end he has in view is to make a good stroke … the moment he begins to play he starts to work for that end directly, without considering what manner of use of his mechanisms generally would be the best for the making of a good stroke. The result is that he makes the stroke according to his habitual use… takes his eyes off the ball and makes a bad stroke. 
End-gaining is Alexander’s way of describing what we do when we concentrate on product instead of the process that will actually help us achieve it. This is what we do when we focus on the notes/melody/music instead of the combination of all the elements that create the product that we call ‘music’.
Process oriented practice
The kind of practice advocated by Westney – what I am terming ‘process oriented practice’ – is much closer to what Alexander would call ‘giving due consideration to the means’ that will enable the desired end to be gained. We need to look not just at the notes, but at space between them. This is the ‘negative space’ where we must complete whatever is necessary physically to get us from one note to the next. In process oriented practice we learn to look at the negative space – the hidden world where we explore fingerings, joint angulations, efficiency of movement. We need to learn to look at the notes as the outcome of the process that occurs in the negative space, because if we successfully complete the mental and physical activities needed in the negative space, the notes will take care of themselves.
Ultimately, we need to learn how to allow ourselves, particularly in the early stages of the rehearsal process, the delicious luxury of exploring HOW we are going to navigate our way between the notes on the page. We need to learn to enjoy the pleasure of exploring the universe of negative space in which the printed notes appear like jewels. If we pay attention to the means, the product will take care of itself.
 Westney, W., The Perfect Wrong Note, Plumpton Plains, Amadeus Music, 2003, p.109. A big thanks to @strawbini of Twitter for introducing me to this book.
 Alexander, F.M., The Use of the Self in the IRDEAT ed., p.436.
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