From here: http://www.wildmind.org/background/symptoms

Some signs and symptoms of inner peace:

• A tendency to think and act spontaneously rather than on fears based on past experiences.
• An unmistakable ability to enjoy each moment.
• A loss of interest in judging other people.
• A loss of interest in judging self.
• A loss of interest in interpreting the actions of others.
• A loss of interest in conflict.
• A loss of the ability to worry. (This is a very serious symptom.)
• Frequent, overwhelming episodes of appreciation.
• Contented feelings of connectedness with others and nature.
• Frequent attacks of smiling.
• An increasing tendency to let things happen rather than make them happen.
• An increased susceptibility to the love extended by others as well as the
  uncontrollable urge to extend it.