science has now been for a long time - and to an ever-increasing extent - a collective enterprise. Actually, new results are always, in fact, the work of specific individuals; but, save perhaps for rare exceptions, the value of any result depends on such a complex set of interrelations with past discoveries and possible future researches that even the mind of the inventor cannot embrace the whole.

I am not a Catholic; but I consider the Christian idea, which has its roots in Greek thought and in the course of the centuries has nourished all of our European civilization, as something that one cannot renounce without becoming degraded.

It is grace that forms the void inside us and it is grace that can fill the void.

The danger is not lest the soul should doubt whether there is any bread, but lest, by a lie, it should persuade itself that it is not hungry.

It is human misery and not pleasure which contains the secret of the divine wisdom.

[We are not] to take one step, even in the direction of what is good, beyond that to which we are irresistibly impelled by God, and this applies to action, word, and thought.

The only hope of socialism resides in those who have already brought about in themselves, as far as is possible in the society of today, that union between manual and intellectual labor which characterizes the society we are aiming at.