What people somehow forgot to mention when we were children was that we need to make messes in order to find out who we are and why we are here.
                                                               —Anne Lamott, Bird By Bird
For one of the workshops of my recent MFA residency (USM: Stonecoast, for those interested), I submitted the first draft of the opening chapter of my current WIP. I left the residency with marked-up manuscripts and editorial letters from six of my peers and a faculty member, and a head full of their discussion.

In other words: I left the residency ready for a revision.

I recently read this article by Bradley P. Beaulieu, discussing ways in which characters change and grow and whether or not this is necessary to a good story. This had me thinking not only about the ways in which characters might change, but the reasons for them—what inspires characters to change, either consciously or unconsciously, and which of these are most effective for a story?

The thing is, people don’t like to change—we’re a rather sedentary species. The saying “if it ain’t broke, don’t fix it” is an attitude for more than just appliances, and inertia affects more than just objects:

“An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.” —Newton’s First Law of Motion (aka the Law of Inertia)

So what sort of “unbalanced force” can make a character change?

Warning: This is less a review and more an essay. It's long, quote-ridden, and spoilery (inasmuch as nonfiction can be spoiled). Also, marginalia!

There's a bit of review-breakdown at the very end, and further reading recommendations, so just scroll down if that's what you're here for.