Several things, people, issues, situations take on the persona of a bull in one's life. And depending on your personal mindframe at that given point of time, you either take it by its horns or duck away. And there in lies your wisdom.
I took on a major bull (French, not Spanish) in my last job and decided to go my way. No regrets, so far!
Then again, life serves you challenging aces again and again, that you need to be able to take by the horns, face them and solve them to your advantage. Isn't this what life is all about!
Like I said, sometimes life is the bull and sometimes you are the bull in somebody else's life.
Or you could also be the bull in a China shop if you donot integrate your personal wherewithal.
So the mantra is, no bull'ing around just finding the best of solutions at the right time.