A powerful agent is the right word. Whenever we come upon one of those intensely right words in a book or newspaper the resulting effect is physical as well as spiritual, and electrically prompt.
Mark TwainDon't just sit there and worry. Be proactive. Do something - anything - about what's worrying you so you can gain information, focus and control over the situation. I've suffered a great many catastrophes in my life. Most of them never happened.
Mark Twain