This quote sits on my desktop at my day job:
"The art of being wise is knowing what to overlook." - William James
When I hunted this quote up, I was experiencing a great deal of stress at work. Every day seemed like a constant series of aggravations and annoyances. Stress made me more sensitive and even the smallest things that I would usually shrug off were getting to me. This all made me extremely unpleasant to live with (just ask my family).
Stepping back and assessing the importance of each of these daily annoyances helped me to put my daily stressors into perspective. A looming deadline for filing a document? That's important. A coworker being rude to me? Not so important. Certainly not worth ratcheting up my stress level when there's work to be done.
Knowing what to overlook has made a difference in my work environment. Wisdom, well, that will come.