Two of my all-time favorite articles about managing one’s energy and time relate to the notion of maintaining “Slack” in one’s life. The first, Slack, by Zvi Mowshowitz, directly describes the Slack concept that I refer to in this post. The second, Sabbath hard and go home, expands on this notion in the context of the author’s Jewish upbringing.

I’ve been wanting to write about this concept for a while, but (ironically) haven’t ever found the time to do so.

Slack (proper noun) is your buffer. It’s your buffer of mental energy, physical energy, and time. It’s the ability to get sick for a day or two without significant interruption to one’s commitments. Slack means you can have an off day without missing an important deadline. Slack allows you to to explore something you’re curious in, without worrying about wasting time. It’s writing a blog post about Slack, when there are assuredly more “valuable” things one could do with one’s time.

In the Stock and Flow model of systems, Slack is a Stock, a quantity that can be built up and depleted. It’s significantly easier to deplete one’s Stock of Slack than increase it. Depleting Slack is easy: Unforseen circumstances, the inevitable chaos in life, and cultural expectations around business and work ethic all make burning through one’s buffer the default outcome. Retaining and rebuilding Slack take purposeful effort.

Maintaining Slack

Maintaining a buffer of Slack requires active effort, especially for people who like to stay busy. I try to use my time well – both at work, and in my personal life – and so I have the tendency to commit to things such that my schedule is “full”. This is manageable when you’re in complete control over your schedule, but as soon as exterior forces exert their influence on your life, you quickly burn through your Slack. So, in one way, Slack is purposefully undercomitting yourself. Zvi defines Slack as “The absence of binding constraints on behavior”, and so in this way, choosing which constraints you allow to be placed on your time is critically important to maintaining a buffer.

Slack also requires handling commitments wisely. Tasks with hard deadlines should be started sooner than necessary, to have buffer time built-in. Unimportant tasks should be deferred or delegated to minimize unnecessarily spent time.

Having ample Slack needs to be the default case for it to be useful. If you sometimes have Slack, but often don’t, you don’t get the benefits. The “badness” of stress quickly outpaces the “goodness” of flexibility. One stressful day or week looms larger than days and weeks without undue stress. Maintaining a buffer should be one’s standard stance.

Failure Modes

Functioning without Slack is like that feeling of always being “one bad event” away from letting something slip. It’s a precarious feeling! Living this way for too long leads to burnout or, at best, fatigue. Lacking Slack results in stressfully working to meet deadlines, dropping commitments, and always being anxious about “what’ll go wrong next”.

One feature I’ve noticed about Slack is that it tends to be global, or “life complete”. One doesn’t have work Slack and personal Slack, as separate quantities. Everything ultimately comes from the same energy and time budget.

That being said, Slack is meant to be used. The optimal amount of burnout is greater than zero. Having Slack, but not using it to pursue worthy goals is a waste. Optimally, one should never get to a place of having no Slack. But this is challenging, as it’s hard to gauge how much Slack actually has. Occasionally overshooting into having too little Slack is OK, as long as you notice this quickly, and work to reestablish that buffer.

Reestablishing Slack

The longer you are without Slack, the harder it is to bring it back. If I find I’m merely running slighly low on Slack, slowing down for a week or two tends to be enough to get back to baseline.

The more dangerous situation is when you get into a longer-term Slackless rut. Getting out of a rut is particularly challenging because (1) getting out of a rut and (2) Slack is what gives you the breathing room to think dynamically. Burnout decreases executive function, and so making the necessary changes to one’s routine to get out of the rut is exactly what’s most challenging to do.

I don’t have a great answer for how to get out of ruts. I’ve found the most reliable way to get out of a rut is to be pushed out by external circumstances. It’s especially helpful to have people in your life who realize you’re in one, and/or can help you climb out of one.

In either case, reestablishing Slack requires redirecting your time and energy. Intentionally do less to build back up a buffer.