Cities are, first of all, seats of the highest economic division of labor.

Gratitude, as it were, is the moral memory of mankind. In this respect, it differs from faithfulness by being more practical and impulsive: although it may remain, of course, something purely internal, it may yet engender new actions. It is an ideal bridge which the soul comes across again and again, so to speak, and which, upon provocations too slight to throw a new bridge to the other person, it uses to come closer to him.

On the one hand, life is made infinitely easy for the personality in that stimulations, interests, uses of time and consciousness are offered to it from all sides. They carry the person as if in a stream, and one needs hardly to swim for oneself.

The psychological basis of the metropolitan type of individuality consists in the intensification of nervous stimulation which results from the swift and uninterrupted change of outer and inner stimuli.

Music and love are the only accomplishments of humanity which do not, in an absolute sense, have to be called attempts with unsuitable means.

The first internal relation that is essential to a secret society is the reciprocal confidence of its members.

Discretion is nothing other than the sense of justice with respect to the sphere of the intimate contents of life.