I seek equanimity.
–noun
mental or emotional stability or composure, esp. under tension or strain; calmness; equilibrium.
Origin:
1600–10; < L aequanimitās, equiv. to aequ(us) even, plain, equal + anim(us) mind, spirit, feelings + -itās -ity
Random House Dictionary, © Random House, Inc. 2009

“Equanimity describes the unattached awareness of one’s experience as a result of perceiving the impermanence of momentary reality. It is a peace of mind and abiding calmness that cannot be shaken by any grade of both fortunate circumstance and unfortunate one. It is a concept promoted by several major religious groups.”
Wikipedia

Although Cornelius Vanderbilt Whitney named his champion thoroughbred racehorse “Equipoise” early in the 20th century, equipoise also relates somewhat to the word equanimity.
equipoise.
-noun
1. Equality in distribution, as of weight, relationship, or emotional forces; equilibrium.
2. A counterpoise; a counterbalance.
The American Heritage® Dictionary of the English Language, Fourth Edition copyright ©2000

“Several of the poems in “Operas and Arias” and “Songs of Self” focus on characters at a moment of equipoise before or at a point of a major decision or traumatic event.”
Music from Words

meditative equipoise is described as an undistracted state of mind achieved through various methods of meditation. Apparently some can achieve total absorption, which, according to a glossary of Buddhist terms archived by Alexander Berzin, means a state of mind in which absorbed concentration is focused single-pointedly on a void.

“Few people are capable of expressing with equanimity opinions which differ from the prejudices of their social environment” ~ Albert Einstein