“The patterns of our lives reveal us. Our habits measure us,” Mary Oliver wrote in contemplating how habit gives shape to our inner lives. “Every smallest stroke of virtue or of vice leaves its never so little scar,” William James asserted a century earlier in his foundational treatise on the psychology of habit. “Good habits, imperceptibly fixed, are far preferable to the precepts of reason,” the pioneering political philosopher and feminist Mary Wollstonecraft insisted yet another century earlier in her Blake-illustrated children’s book of moral education. But if our imperceptibly fixed habits incline more toward vice more toward virtue, what does it take to reconfigure these scarred and scarring patterns?

That is what William Shakespeare — another seer of elemental truth and keen observer of human psychology — examined long before Oliver, James, and Wollstonecraft, in Hamlet. In eleven exquisitely insightful lines of blank verse, he frames the central premise of what would come to be known, a dozen generations later, as cognitive behavioral therapy.

In Act III, Scene 4 — a passage quoted in founding father and mental health reformer Benjamin Rush’s landmark speech on the influence of physical habits upon mental health — Hamlet counsels his mother, Gertrude:

Assume a virtue, if you have it not.
That monster, Custom, who all sense doth eat
Of habits evil, is angel yet in this,
That to the use of actions fair and good
He likewise gives a frock or livery,
That aptly is put on. Refrain to-night,
And that shall lend a kind of easiness
To the next abstinence; the next more easy:
For use can almost change the stamp of nature,
And master even the devil, or throw him out,
With wondrous potency.

Couple with Nicole Krauss’s beautiful letter to Van Gogh across space and time about how to break the loop of our destructive patterns, then revisit James Baldwin on the source of Shakespeare’s genius of insight and Meghan O’Rourke on how Shakespeare can shepherd us through our grief and despair.