We don't generate creativity by sheer force. We experience it by stepping back. The reason you feel creative when you start a new job, is because the problem set is new - and so the job behaves like a side project in those first few months. The same is true of stepping into someone else's writing - you perceive the writer's grind from a distance, allowing your insight to flow freely and easily - sometimes producing an "of course!" reaction (in the writer) typical of someone who was trying, with all their will, to uncover that same insight.
Side projects exist to refresh the mind. They're our version of a â€˜Shut Down' command.
Lately, I am more busy than I've ever been in my life before (feels great, before you ask). GrantTree is buzzing in all sorts of ways which mean that I am happily working every evening I can claw in. Once upon a time, I might have come back home and relaxed in front of the TV. For the last couple of months, I've felt so driven than I just don't feel motivated to do nothing (hah).
But you do need to do something else to remain productive. For me, it's going to the gym (which takes a chunk of time but is absolutely worthwhile from many different perspectives), going to 3-hour acting classes every Tuesday evening, reading Lord of the Rings to my fiancÃ©e, spending dedicated time in a cafÃ© with my iPad and Origami case and writing fiction, or even giving talks to or mentoring startups!
Those things, which have little or nothing to do with GrantTree's main activity, keep me sane and grounded and enable me to be creative in my daily work.
So yes, this is an extremely valid purpose for side projects: to maintain sanity and creativity in a busy life.
When you have no time for side projects is probably the point in your life where you need them most.
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