Perhaps my most favorite thing to muse over is creativity. Just how do humans come up with their ideas? How do we keep generating new things to amuse, challenge, upset, inspire? The ancient Greeks (and, even more, Renaissance Italians) liked to personify the urge to create with a variety of female demi-goddesses. I guess it's easier to blame some willful divinity for your writer's block, than waiting around for your synapses to start firing.
My professional trajectory has been one that often intersects with one or another of the classical muses (altho these girls weren't really standardized and assigned specializations until Cesare Ripa's Iconologia in 1593); journalism (Calliope)-art history (Clio)-costume design (Melpolmene/Thalia)-and, in a way, back to journalism. It's been a mix of being creative and studying creativity and justifying creativity (to an actress whose ability to create is dependent on whether she thinks she looks fat or not).
The act of creation; sometimes the urge and the ideas overwhelm in their volume, other times it's impossible to even get started. They say, it's a matter of the brain's ability to operate outside of usual patterns, often facilitated by letting the mind wander or doing something relaxing (like knitting or, ahem, doing yoga) to shift the task into an auxiliary system. Putting it on the back burner, if you will. But, it's funny how a deadline--decidedly not relaxing--can help accelerate the process. Sometimes the most brilliant work comes at the last moment (altho that's usually not the best strategy for something that requires careful proofreading). Adrenaline? Activated sympathetic nervous system?
However, like the ancient Greeks, to me it feels like some external presence/inspiration arrives after the usual pre-work puttering (facebook, putting away dishes, a round of shanghai). I get about an hour to an-hour-an-a-half of productivity and then, like a sputtering match, the words stop coming and my creativity flickers out. It's the same with writing or with drawing, whether being eloquent with words or proportional with a drawing of the human figure. Bye, bye, muse, and it gets all redundant and ugly. The steel doors come slamming shut. (I wonder what that sez about my brain's circuitry...limited and prone to blowing a fuse?)
Anyway, interesting to ponder. Any metaphors you'd like to add? How does the muse visit you?