Freedom is indivisible, and when one man is enslaved, all are not free.

No government or social system is so evil that its people must be considered as lacking in virtue.

The American presidency will demand more than ringing manifestos issued from the rear of the battle. It will demand that the President place himself in the very thick of the fight; that he care passionately about the fate of the people he leads .

I want to emphasize in the great concentration which we now place upon scientists and engineers how much we still need the men and women educated in the liberal tradition, willing to take the long look, undisturbed by prejudices and slogans of the moment, who attempt to make an honest judgment on difficult events.

Forbidden fruit tastes sweet, but its aftertaste is bitter.

All over the world, particularly in the newer nations, young men are coming to power--men who are not bound by the traditions of the past--men who are not blinded by the old fears and hates and rivalries-- young men who can cast off the old slogans and delusions and suspicions.

We stand today on the edge of a new frontier - the frontier of the 1960's - a frontier of unknown opportunities and perils - a frontier of unfulfilled hopes and threats.