A little anxiety isn't necessarily a bad thing, says Alice Park in TIME. That on-edge feeling can actually help us function at our best. "Philosophers and poets, from their perch on the cutting edge of reason, have always seen the advantage of anxiety," she says (subscription required). T.S. Eliot called it the "handmaiden of creativity"; novelist Angela Carter referred to it as "the beginning of conscience." And for everyone from firefighters to professional athletes to neurotic comedians, anxiety isn't a crippling fear — it's a "critical ingredient" in the recipe for peak performance. The key, Park says, isn't fighting off anxiety or numbing ourselves with Xanax or Valium, but learning how to manage the sensation — "metabolic jujitsu," if you will — and using it as an asset. Here, an excerpt:

For all the suffering anxiety causes, the fact is, the species would not be better off without it — and we might not be here at all. At its core, anxiety is a reaction, an arousal to a stimulus that we perceive as dangerous or threatening. The fabled saber-toothed tiger springs at the primitive human, and the human reacts with a biological red alert, bypassing the relatively time consuming thinking centers in the brain in favor of a shortcut directly to the deeper-seated hypothalamus. This awakens the nervous system to release hormones that instantly rev up heart rate and respiration, feeding fresh blood and oxygen to the muscles, which need the boost to carry the human as quickly and as far away from danger as possible… It's a nifty response, one that produced a lot of people who would live to see another day, and, more important, sire new generations of babies who would inherit their hair-trigger reflexes.

In fact, it's this dual face of anxiety that has made it such a permanent part of the evolutionary recipe for the human species.

Read the entire article at TIME (subscription required)