My favourite president, and the one I admired most, was Harry Truman.

Building confidence and constructive relations between Sudan and South Sudan is urgent

One of the greatest concerns that I had when I became President was the vast array of nuclear weapons in the arsenals of the United States and the Soviet Union and a few other countries, and also the great proliferation of conventional weapons, non-nuclear weapons, particularly as a tremendous burden on the economies of developing or very poor countries.

Earlier in my life I thought the things that mattered were the things that you could see, like your car, your house, your wealth, your property, your office. But as I've grown older I've become convinced that the things that matter most are the things that you can't see -- the love you share with others, your inner purpose, your comfort with who you are.

In many courts, plea bargaining serves the convenience of the judge and the lawyers, not the ends of justice, because the courts simply lack the time to give everyone a fair trial.

I am no big shot. I am not anybody's boss. I want to be everybody's servant.

During the period of the Saturn-Apollo missions we were pilgrims in space, ranging from home in search of knowledge. Now we will become shepherds tending our technological flocks, but like the shepherds of old, we will keep our eyes fixed on the heavens.