“It must not be forgotten that reason too needs to be sustained in all its searching by trusting dialogue and sincere friendship. A climate of suspicion and distrust, which can beset speculative research, ignores the teaching of the ancient philosophers who proposed friendship as one of the most appropriate contexts for sound philosophical enquiry.”

“No one else can want for me. No one can substitute his act of will for mine. It does sometimes happen that someone very much wants me to want what he wants. This is the moment when the impassable frontier between him and me, which is drawn by free will, becomes most obvious. I may not want that which he wants me to want - and in this precisely I am incommunicabilis. I am, and I must be, independent in my actions. All human relationships are posited on this fact.”

“Friendship, as has been said, consists in a full commitment of the will to another person with a view to that person's good.”

“Love consists of a commitment which limits one's freedom - it is a giving of the self, and to give oneself means just that: to limit one's freedom on behalf of another.”

“Do not be afraid to take a chance on peace, to teach peace, to live peace...Peace will be the last word of history.”

“Humankind, which discovers its capacity to transform and in a certain sense create the world through its own work, forgets that this is always based on God's prior and original gift of things that are. People think that they can make arbitrary use of the earth, subjecting it without restraint to their wills, as though the earth did not have its own requisites and a prior God-given purpose, which human beings can indeed develop but must not betray.”

“Life is entrusted to man as a treasure which must not be squandered, as a talent which must be used well.”