The distinction between practice and play for musicians is fairly clear. A musician spends most of her time in the privacy of her practice room working on her music. She spends a comparatively small amount of time playing her music for audiences. There is a clear boundary between these two activities.
In practice, the conscious focus is on the minutiae. One focuses on the fingering, clarity of notes, being in rhythm, being on time, getting it all right. One brings a totally conscious awareness to the practice process. One listens to every sound, feels every sensation, and maintains a clear intention of what one wants to achieve. And all of this is toward sensitizing your body to the music and training your subconscious correctly.
In play, one puts the conscious mind to rest and lets the subconscious carry one through. Play is about feel. It is about flow. It is about letting go and letting the music take you. Only the greatest musicians are able to maintain this flow through an entire performance. And this capacity is earned through decades of the right kind of practice.
In other words, practice is about developing technique and skill while play is about letting the skill thus developed take a life of its own and lead you.
And the loop closes: it is perfectly natural for a musician to leave every performance with a tinge of dissatisfaction. She knows where her skill let her down, and she takes that feedback to the practice room to strengthen what turned out to be weak. And next time she is a bit better.
Musicians (and performing artists in general) seem to take this separation for granted. Not so much for the rest of us. Yet I feel that there is a lot to be gained by viewing all creative disciplines through the lenses of practice and play. This is because all creative disciplines require technique, and they all involve an element of flow and inspiration.
We tend not to think of non-performing activities in the terms of practice and play because there is no clear element of performance. We can't answer the questions 'What constitutes my technique?' and 'What does performing mean to me?' as clearly as a musician can.
But there is technique in programming, in writing, in debating, in conversing, in teaching, in mathematics etc. There are huge gains to be had from knowing what this technique is and knowing how to develop it. And it is equally important to know when to let go and trust the instincts developed through practice.
As a programmer, the hours spent hacking on technology when I was in school, and the hours spent fussing over simple mathematical proofs in college were the essential practice. It developed the mathematical and technical skills needed to work with machines and design elegant systems. And the practice continues as a professional. I am constantly inventing new systems and new solutions. But I am also consciously noting the deficiencies in the systems I have built and looping that feedback into my newer designs. I learn from others experiences in a similar way. The practice and performance are more intermingled, but they are distinct activities nonetheless.
Any capability which requires technique, skill, and inspiration is born through the processes of practice and play. Being aware of this dynamic and using it to ones advantage is crucial for continual growth and optimal performance.