Is acedia depression? My answer is No, not exactly, but I must struggle to articulate the difference with precision.
—Kathleen Norris, Acedia and Me, p24

Emphatically not the same. I can tell from the inside.

When I observe the outward signs (including struggling to get out of bed, not tackling even the smallest of house-tasks available, human contact narrowing to those in my space—these signs are, in fact, nearly identical in both) I apply the techniques my therapist Thea taught me. She taught me to go from outside in, since I had to train myself to identify feelings—my outside still is often my earliest warning. Once alerted, I probe recent activities, reviewing them in memory for twinges of sadness or anger or both, which in me is despair.

I’ll range back pretty far if I keep coming up neutral.

If the behavior is depressive and the interior aligns, I have sussed out depression’s nub, and can move ahead in caring for it. Like my errant blood sugar levels, depression is a threat and I strive to weed it out briskly. No quarter; I can’t afford the luxury of hoping it will drift away of its own accord.

If the behavior is depressive, and the interior is neutral…I don’t have a plan for that. Acedia becomes luxury, as if it were a cry for rest. I read and read…which if it were a cry for rest, would peter out in a handful of days. In real life, I get bored. Not so much in acedic life.

In fact, Norris acquired a solid delineation. She quotes an unnamed contemporary scholar in summarizing Aquinas:

For despair, participation in the divine nature through grace is perceived as appealing, but impossible; for acedia, the prospect is possible, but unappealing.

It’s when I recognize that possibility that I recognize the noonday demon has me again.