1) "Ignorance, when voluntary, is criminal, and a man may be properly charged with that evil which he neglected or refused to learn how to prevent.","Samuel Johnson, The History of Rasselas, Prince of Abissinia"

2) "My optimism and confidence come not from feeling I'm luckier than other mortals, and they sure don't come from visualizing victory. They're the result of a lifetime spent visualizing defeat and figuring out how to prevent it. Like most astronauts, I'm pretty sure that I can deal with what life throws at me because I've thought about what to do if things go wrong, as well as right. That's the power of negative thinking.","Chris Hadfield, An Astronaut's Guide to Life on Earth"

3) Waiting on God is not in vain!,"Nancy Gavilanes, Waiting on God Well: how to prevent Breaking Down on Your Way to Your Breakthrough"

4) "The special skill of the politician consists in knowing what passions can be most easily aroused, and how to prevent them, when aroused, from being harmful to himself and his associates...Moreover, since politicians are divided into rival groups, they aim at similarly dividing the nation, unless they have the good fortune to unite it in war against some other nation.","Bertrand Russell, Sceptical Essays"